Lysosomal targeting bifunctional molecules for degradation of thyroid stimulating hormone receptor autoantibodies

Abstract

The present disclosure provides lysosomal targeting bifunctional molecules that target disease causing anti-TSHR autoantibodies for degradation. The lysosomal targeting bifunctional molecules include a ligand moiety that specifically binds to an asialoglycoprotein receptor (ASGPR), and which is linked via a carrier protein to a thyroid stimulating hormone receptor (TSHR) polypeptide that specifically binds target anti-TSHR autoantibodies.

Description

[0001] Attorney Ref: 92VF-350823-WO Client Ref: 021WO LYSOSOMAL TARGETING BIFUNCTIONAL MOLECULES FOR DEGRADATION OF THYROID STIMULATING HORMONE RECEPTOR AUTOANTIBODIES CROSS REFERENCE TO RELATED APPLICATIONS The present application claims priority to U.S. Patent Application No.63 / 571,393, filed March 28, 2024, the content of which is incorporated herein by reference in its entirety in the present disclosure. BACKGROUND Many therapeutics act by binding a functionally important site on a target protein, thereby modulating the activity of that protein, or by recruiting immune effectors, as with many monoclonal antibody drugs, to act upon the target protein. However, there is an untapped reservoir of medically important human proteins that are considered to be “undruggable” because these proteins are not readily amenable to currently available therapeutic targeting approaches. Graves’ disease is an autoimmune disease that primarily affects the thyroid gland and is caused by autoantibodies to the thyroid-stimulating hormone receptor (TSHR). (T.F. Davies et al., Graves’ Disease, Nature Reviews - Disease Primers, 6:52 (2020)). Graves’ Disease, also known as von Basedow disease, is characterized by an enlarged and overactive thyroid gland (Graves’ hyperthyroidism). Other symptoms include arrythmia, goiter, irritability, fatigue, weight-fluctuation, bone loss; extrathyroidal manifestations including orbitopathy (thyroid eye disease, TED), and pre-tibial skin thickening or rash. Graves’ Disease affects approximately 2% of women and 0.2% of men globally. Current treatments include antithyroid drugs, radioiodine and surgery. The treatment of patients with GD has not changed in many years and newer, more effective therapies could improve outcomes. Thyroid eye disease (TED), also known as thyroid-associated orbitopathy, Graves ophthalmopathy and Graves orbitopathy, is an autoimmune condition that can be disfiguring and impair sight. (Kossler et al.) In the United States, TED affects approximately 16 of every 100,000 females and 3 of every 100,000 males. Improved treatments over the current standards of care for both Graves’ disease and TED are needed. LYTACs (lysosomal targeting chimera) are bifunctional molecules for selective protein degradation. The first LYTACs targeted extracellular proteins for degradation via engaging the cation- independent mannose-6-phosphate receptor (CI-M6PR) or the asialoglycoprotein receptor (ASGPR). ASGPR is the transmembrane glycoprotein receptor found primarily in hepatocytes which plays an important role in serum glycoprotein homeostasis by mediating the endocytosis and lysosomal degradation of glycoproteins with exposed terminal galactose or N-acetylgalactosamine (GalNAc) residues. Attorney Ref: 92VF-350823-WO Client Ref: 021WO SUMMARY The present disclosure provides lysosomal targeting bifunctional molecules (LYTACs, also referred to as conjugates) that target disease-causing anti-TSHR autoantibodies for degradation. The lysosomal targeting bifunctional molecules include a ligand moiety that specifically binds to an asialoglycoprotein receptor (ASGPR), and TSHR autoantigen that binds pathogenic autoantibodies. In some embodiments, provided is a conjugate (i.e., LYTAC), of Formula I: X (L1)a(L2)b(L3)c(L4)d(L5)e L6Y-B I or a prodrug n is 1 to 10; m is 1 to 10; X is a moiety that binds to asialoglycoprotein receptor (ASGPR); Y is a carrier polypeptide connected to B; B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody; each L1to L6is independently a linking moiety which together provide a linear or branched linker between each X and the Y-B complex; and a, b, c, d, and e are each independently 1, 2, 3, 4, or 5. In some embodiments, B comprises an extracellular domain of TSHR or a fragment thereof. In some embodiments, B comprises a polypeptide having at least 80% (e.g., at least 85%, or at least 90%) sequence identity with a sequence of SEQ ID NOs: 1-7. In some embodiments, B comprises a polypeptide having at least 95% sequence identity with a sequence of SEQ ID NOs: 1-7. In some embodiments, B comprises a polypeptide having at least 98% sequence identity with a sequence of SEQ ID NOs: 1-7. In some embodiments, B comprises a polypeptide of one of SEQ ID NOs: 1-7. In some embodiments, B consists essentially of a polypeptide of one of SEQ ID NOs: 1-7. In some embodiments, B has one or more amino acid substitutions selected from R112P, D143P, D151E, V169R, C176S, K250Q, and I253R as compared to a sequence of SEQ ID NO: 1-7. In some embodiments, B has one or more amino acid substitutions selected from H63C, R112P, D143P, D151E, V169R, I253R as compared to a sequence of SEQ ID NO: 1-7. Attorney Ref: 92VF-350823-WO Client Ref: 021WO In some embodiments, Y is selected from albumin, albumin binding domain, multimerization domain, Fc domain, Fc (monomer), Fc (dimer), fragments thereof (e.g., synthetic peptides), and variants thereof. In some embodiments, Y comprises an albumin, a fragment thereof, or a variant thereof. In some embodiments, Y comprises human serum albumin (HSA), an HSA domain, bovine serum albumin (BSA), a fragment thereof, or a variant thereof. In some embodiments, Y is an HSA variant engineered for increased stability, conjugation efficiency (Cys or Lys), and / or FcRn binding. In some embodiments, Y comprises a polypeptide having 1 to 10 amino acid substitutions, deletions or additions (for example, 1, 2, 3, 4 or 5 amino acid substitutions, deletions or additions) as compared to a sequence of SEQ ID NOs: 8- 12, 14 and 15. In some embodiments, the 1 to 10 amino acid substitutions, deletions or additions are selected from C34A, V54C, K93C, H128C, K262C, and E294C. In some embodiments, Y comprises a site-specific mutation of a naturally occurring amino acid residue. In some embodiments, Y comprises a polypeptide having at least 80% (e.g., at least 90%, at least 95%, at least 98%) sequence identity with a sequence of SEQ ID NOs: 8-12, 14 and 15. In some embodiments, Y comprises a polypeptide of one of SEQ ID NOs: 8-12, 14 and 15. In some embodiments, Y comprises a Fc domain, a fragment thereof, or a variant thereof. In some embodiments, Y comprises Fc (monomer). In some embodiments, Y comprises Fc (dimer). In some embodiments, Y comprises a Fc domain engineered for increased stability, conjugation efficiency (Cys or Lys), and / or FcRn binding. In some embodiments, Y comprises a polypeptide having 1 to 10 amino acid substitutions, deletions or additions (for example, 1, 2, 3, 4 or 5 amino acid substitutions, deletions or additions) as compared to a sequence of SEQ ID NO: 15. In some embodiments, the 1 to 10 amino acid substitutions, deletions or additions are selected from T366W, T366S, X368A, A378C, X407V, and L443C. In some embodiments, Y comprises a polypeptide having at least 80% (e.g., at least 90%, at least 95%, at least 98%) sequence identity with a sequence of SEQ ID NO: 15. In some embodiments, Y comprises a polypeptide of SEQ ID NO: 15. In some embodiments, Y-B is a chimeric fusion protein. In some embodiments, Y-B is selected from an Fc-TSHR fusion, and an HSA-TSHR fusion. In some embodiments, Y is covalently linked to B via a linker. In some embodiments, the linker comprises a non-peptidic linking moiety. In some embodiments, Y is fused directly to B. In some embodiments, Y is fused indirectly to B via a spacer domain. In some embodiments, the N-terminal of Y is fused to the C-terminal of B. In some embodiments, the C-terminal of Y is fused to the N-terminal of B. In some embodiments, Y is covalently linked to B via a non-peptidic linking moiety (e.g., a bifunctional linker). In some embodiments, n is from about 2 to about 10. In some embodiments, n is 3. Attorney Ref: 92VF-350823-WO Client Ref: 021WO In some embodiments, m is 4 to 6. In some embodiments, Y-B comprises any one of SEQ ID NOs: 1-7. In some embodiments, B comprises any one of SEQ ID NOs: 1-7. In some embodiments, B comprises SEQ ID NO: 6. In some embodiments, Y comprises any one of SEQ ID NOs: 8, 9, 10, 11, 12, 14, and 15. In some embodiments, Y comprises SEQ ID NOs: 15. In some embodiments, B comprises SEQ ID NO: 6 and Y comprises SEQ ID NOs: 15. In some embodiments, B is SEQ ID NO: 6 and Y is SEQ ID NOs: 15. In some embodiments, L is conjugated to one or more lysine residues of Y or B. In some embodiments, L is conjugated to one or more cysteine residues of Y. In some embodiments, provided is a conjugate (i.e., LYTAC), of Formula: HO OO ONH B m is 4 to 6; Y is a carrier polypeptide connected to B, wherein the carrier polypeptide is HSA comprising SEQ ID NO: 15; and B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody, comprising SEQ ID NO: 6. In some embodiments, provided is a conjugate (i.e., LYTAC), of Formula: Attorney Ref: 92VF-350823-WO Client Ref: 021WO HO HNO HO B m is 4 to 6; Y is a carrier polypeptide connected to B, wherein the carrier polypeptide is HSA comprising SEQ ID NO: 15; and B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody, comprising SEQ ID NO: 6. In some embodiments, provided is a conjugate (i.e., LYTAC), of Formula: O B Attorney Ref: 92VF-350823-WO Client Ref: 021WO Y is a carrier polypeptide connected to B, wherein the carrier polypeptide is HSA comprising SEQ ID NO: 15; and B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody, comprising SEQ ID NO: 6. In some embodiments, provided is a conjugate (i.e., LYTAC), of Formula: HO HO HO B m is 4 to 6; Y is a carrier polypeptide connected to B, wherein the carrier polypeptide is HSA comprising SEQ ID NO: 15; and B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody, comprising SEQ ID NO: 6. In some embodiments, Y is connected to B via a linking sequence. In some embodiments, linking sequence comprises GGGGSGGGGSGGGGS (SEQ ID NO: 16). In some embodiments, provided is a conjugate (i.e., LYTAC), of Formula: Attorney Ref: 92VF-350823-WO Client Ref: 021WO HO OO OHO NH NH B m is 4-6; Y is a carrier polypeptide connected to B, wherein the carrier polypeptide is HSA comprising SEQ ID NO: 15 ; B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody, comprising SEQ ID NO: 6; and Y is connected to B via a linking sequence comprising GGGGSGGGGSGGGGS (SEQ ID NO: 16). In some embodiments, provided is a conjugate (i.e., LYTAC), of Formula: HO HNB Attorney Ref: 92VF-350823-WO Client Ref: 021WO wherein: m is 4-6; Y is a carrier polypeptide connected to B, wherein the carrier polypeptide is HSA comprising SEQ ID NO: 15; B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody, comprising SEQ ID NO: 6; and Y is connected to B via a linking sequence comprising GGGGSGGGGSGGGGS (SEQ ID NO: 16). In some embodiments, provided is a conjugate (i.e., LYTAC), of Formula: OOO HN B m is 4-6; Y is a carrier polypeptide connected to B, wherein the carrier polypeptide is HSA comprising SEQ ID NO: 15; B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody, comprising SEQ ID NO: 6; and Y is connected to B via a linking sequence comprising GGGGSGGGGSGGGGS (SEQ ID NO: 16). In some embodiments, provided is a conjugate (i.e., LYTAC), of Formula: Attorney Ref: 92VF-350823-WO Client Ref: 021WO HO HO HO B m is 4-6; Y is a carrier polypeptide connected to B, wherein the carrier polypeptide is HSA comprising SEQ ID NO: 15; B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody, comprising SEQ ID NO: 6; and Y is connected to B via a linking sequence comprising GGGGSGGGGSGGGGS (SEQ ID NO: 16). In some embodiments, the conjugate facilitates internalization of anti-TSHR autoantibody into human cells. In some embodiments, the conjugate facilitates accumulation of anti-TSHR autoantibody in an acidic intracellular compartment of human cells. In some embodiments, the conjugate facilitates degradation of anti-TSHR autoantibody by lysosome in the human cells. In some embodiments, provided is a method of reducing levels of an extracellular anti-TSHR autoantibody in a patient, the method comprising administering an effective amount of a LYTAC or conjugate as described herein. In some embodiments, the administration increases internalization of anti- TSHR autoantibody. In some embodiments, the internalized anti-TSHR autoantibody accumulates into an acidified endosome compartment. In some embodiments, the administration facilitates degradation of the anti-TSHR autoantibody. In some embodiments, the administration results in decrease of greater than 80% Attorney Ref: 92VF-350823-WO Client Ref: 021WO of extracellular anti-TSHR autoantibody level in the patient. In some embodiments, the anti-TSHR autoantibody is M22 or K1-18. In some embodiments, provided is a method of treating Graves’ disease in a patient in need thereof, the method comprising administering to the subject an effective amount of a LYTAC or conjugate as described herein. In some embodiments, the administration increases internalization of anti-TSHR autoantibody. In some embodiments, the internalized anti-TSHR autoantibody accumulates in an acidified endosome compartment. In some embodiments, the administration facilitates degradation of the anti- TSHR autoantibody. In some embodiments, the administration results in decrease of greater than 80% of extracellular anti-TSHR autoantibody level in the patient. In some embodiments, the anti-TSHR autoantibody is M22 or K1-18. BRIEF DESCRIPTION OF THE DRAWINGS These and other features, aspects, and advantages of the present disclosure will become better understood with regard to the following description and accompanying drawings. FIGs.1A-1B show illustrations of LYTAC formats. FIGs.2A-C show improved stability and binding of a stabilized form of TSHR over that of the wild-type. FIGs.3A-B show the results of a cellular uptake assay of autoantibodies by a TSHR-based LYTAC. FIG.4 shows the results of an internalization assay, where LYTACs mediated internalization of an anti-TSHR antibody into an acidified compartment. FIG.5 shows results of a cellular uptake assay, where LYTACs with the K250Q mutation performed equivalently to LYTACs that did not contain this mutation. FIG.6 shows LYTAC-mediated uptake of a pathogenic anti-TSHR antibody, and comparisons with a non-binding control and in ASGPR1 / 2 knock-out cells. FIG.7 shows that LYTACs do not bind TSH, as measured by BLI. FIGs.8A-B show binding kinetics of a LYTAC to two anti-TSHR antibodies. FIG.9 shows results of an uptake assay, comparing the effect of LPR on the degree of antibody uptake. FIGs.10A-B show results of a degradation assay, where a LYTAC mediated lysosomal degradation of a pathogenic anti-TSHR antibody in a dose-dependent manner. Attorney Ref: 92VF-350823-WO Client Ref: 021WO FIG.11 shows results of a degradation assay in which LYTACs mediated degradation of a pathogenic anti-TSHR antibody in hepatocytes. FIG.12 shows results of a depletion assay in which LYTACs mediated depletion of anti-TSHR autoantibodies from patient serum. FIGs.13A-F show results of in vivo experiments where LYTACs mediated clearance of anti- TSHR antibodies. FIG.14 shows that a single 10 mg / kg dose of a LYTAC resulted in complete clearance of an anti-TSHR antibody from circulation in vivo. FIG.15 shows the results of an active immunization adoptive transfer model, in which LYTACs mediated the clearance of a mixture of anti-TSHR antibodies. FIG.16 shows the serum level of biotin-labeled K1-18 hFcRn Tg32 mice after administration of LYTACs to hFcRn Tg32 mice. DETAILED DESCRIPTION A lysosome-targeting chimera (LYTAC) is a protein-based therapeutic designed to bind and rapidly clear, via targeted degradation, thyroid stimulating hormone receptor (TSHR) autoantibodies. Structurally, in some embodiments, a fusion protein of a TSHR polypeptide and human serum albumin that is conjugated, using nonspecific lysine conjugation, to a linker-internalizer comprising a non- cleavable linker bound to a stabilized tri-GalNAc derivative. The fusion protein binds to anti-TSHR autoantibodies, while the linker-internalizer promotes rapid systemic clearance mediated by cellular uptake via binding to the liver specific asialoglycoprotein receptor (ASGPR). ASGPR is a heterotrimer with two ASGPR1 and one ASGPR2 subunits. The human ASGPR1 carbohydrate recognition domain shares 79-99% sequence identity across monkey, dog, rabbit, rat and mouse proteins and complete conservation of residues within 5 Å of a bound GalNAc based on a co-crystal structure. No structural information is available for ASGPR2, but the human carbohydrate recognition domain shares 67-96% sequence identity across monkey, dog, rabbit, rat, and mouse proteins. Furthermore, ASGPR-mediated liver distribution of GalNAc-conjugated siRNAs has been demonstrated for rat and monkey (McDougall et al, 2021). As summarized above, this disclosure provides lysosomal targeting bifunctional molecules (also referred to as conjugates or LYTACs) that target disease causing anti-TSHR autoantibodies for degradation. The lysosomal targeting bifunctional molecules include a ligand moiety that specifically Attorney Ref: 92VF-350823-WO Client Ref: 021WO binds to an asialoglycoprotein receptor (ASGPR), and which is linked to a thyroid stimulating hormone receptor (TSHR) polypeptide that specifically binds target anti-TSHR autoantibodies. 1.1 Lysosomal Targeting Bifunctional Molecules (LYTACs) In some embodiments, a conjugate binds pathogenic anti-TSHR antibodies in circulation and forms a ternary complex with a liver-specific internalizing receptor, ASGPR. After clathrin-mediated endocytosis, the protein complex progresses through the endocytic pathway whereby ASGPR dissociates due to decreasing pH and Ca2+levels and is recycled to the cell surface. A conjugate and the pathogenic antibody continue to the lysosome where they are degraded by lysosomal proteases. The bifunctional molecules (e.g., conjugates or LYTACs) of this disclosure having a particular configuration of ASGPR binding moieties (X) with a linker of desired valency and / or length can specifically bind with high affinity to both the ASGPR receptor and a target anti-TSHR antibody simultaneously and exhibit high uptake activity of the target autoantibody. The conjugates of this disclosure can provide for sequestering and degrading of a target anti-TSHR autoantibody in the cell’s lysosome. In some embodiments, the lysosomal targeting bifunctional molecule is a conjugate of Formula I: Xa c e L6Y-B I or a n is 1 to 10; m is 1 to 10; X is a moiety that binds to asialoglycoprotein receptor (ASGPR); Y is a carrier polypeptide connected to B; B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody; each L1to L6is independently a linking moiety which together provide a linear or branched linker between each X and the Y-B complex; and a, b, c, d, and e are each independently 1, 2, 3, 4, or 5. Attorney Ref: 92VF-350823-WO Client Ref: 021WO In some embodiments, L6comprises a residual moiety resulting from the covalent linkage of a thiol-reactive chemoselective ligation group to one or more cysteine residue(s) of Y-B; or L6is a residual moiety resulting from the covalent linkage of an amine-reactive chemoselective ligation group to one or more lysine residue(s) of Y-B. In some embodiments, Y-B is a chimeric fusion protein (i.e., Y-B complex) including a carrier polypeptide and a polypeptide that specifically binds the target anti-TSHR autoantibody. It is to be understood that each X can be independently bonded to Y or B of the Y-B chimeric fusion protein via the linking moiety, e.g., one or more X can be bonded to Y and one or more X can be bonded to B. Each of the components of the lysosomal targeting bifunctional molecules, configurations of such molecules, and methods of using the same, are now described in greater detail. In some embodiments, n is from about 2 to about 10. In some embodiments, n is from about 2 to about 9, from about 2 to about 8, from about 2 to about 7, from about 2 to about 6, from about 2 to about 5, from about 2 to about 4. In some embodiments, n is 3. In some embodiments, n is about 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. In some embodiments, m is about 1 to about 10, about 1 to about 8, about 1 to about 6, about 2 to about 10, about 2 to about 8, about 2 to about 6, about 4 to about 8, about 4 to about 6, about 4 to about 5, about 5 to about 8, or about 5 to about 6. In some embodiments, m is about 1, 1.5, 2, 2.5, 3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, 7, 7.5, 8, 8.5, 9, 9.5, or 10, or any value between them. In some embodiments, m is about 4 to about 6. 1.1.1 ASGPR Ligand Moieties An asialoglycoprotein receptor (ASGPR) ligand moiety is a moiety that binds to ASGPR (i.e., also referred to as an ASGPR binding moiety) and, via the ASGPR, facilitates internalization of the bifunctional molecule of which it is a part, plus any bound target molecule, e.g., autoantibody. The ASGPR ligand moieties of this disclosure can be connected via a linker to a polypeptide construct without impacting the specific binding to, or function of, the cell surface ASGPR. The lysosomal targeting bifunctional molecules of this disclosure which include one or more linked ASGPR ligand moieties can utilize the functions of cell surface ASGPRs in a biological system, e.g., for internalization and / or sequestration of autoantibody to the lysosome of a cell, and subsequent lysosomal degradation, e.g., in the methods of this disclosure. ASGPR, also known as the Ashwell Morell receptor, is a transmembrane glycoprotein receptor found primarily in hepatocytes which mediates the endocytosis and lysosomal degradation of glycoproteins with exposed terminal galactose or N-acetylgalactosamine (GalNAc) residues. ASGPR Attorney Ref: 92VF-350823-WO Client Ref: 021WO cycles between intracellular endosomes and the cell surface. In some embodiments, the ASGPR is Homo sapiens asialoglycoprotein receptor 1 (ASGR1) (see, e.g., NCBI Reference Sequence: NM_001197216). ASGPR binding compounds and conjugates are described in International Publication WO2023 / 288033 or WO2022 / 142377 the disclosure of which are incorporated by reference herein in their entirety. In some embodiments, the ASGPR binding moiety (X) includes an amino sugar ring analog of galactose (e.g., N-acetylgalactosamine, or analogs thereof) that is connected to a linker scaffold via an optional linking moiety at the 1-, 2- or 6-position of the sugar ring analog. In some embodiments, the linking moiety includes an oxygen, sulfur, nitrogen or carbon atom connected at the 1-position of the ring. In some embodiments, the linking moiety includes an oxygen, sulfur, nitrogen, or carbon atom connected at the 2-position of the ring. In some embodiments, the linking moiety includes an oxygen, sulfur, nitrogen, or carbon atom connected at the 1-position of the ring. In some embodiments, the linking moiety connected at the 1-, 2-, or 6-position of the ring includes an optionally substituted aryl or heteroaryl group. In some embodiments, the amino sugar ring analog of galactose has a bicyclic structure. In some embodiments, the ASGPR ligand moieties (e.g., each X, optionally with the linker or a portion thereof, prior to conjugation) of the bifunctional molecule specifically bind to ASGPR with an affinity (Kd) of 300 nM or less, such as 100 nM or less, 30 nM or less, 10 nM or less, 3 nM or less, or 1 nM or less. The terms “binds,” “binds to,” “specifically binds,” or “specifically binds to” in this context are used interchangeably. In some embodiments of the conjugates described herein, X is an asialoglycoprotein receptor (ASGPR) binding moiety of Formula II: R66 II wherein: R1is selected from -Z1-*, -H, -OH, optionally substituted (C1-C6)alkyl, -OCH3,-OCH2CH=CH, optionally substituted -S-(C1-C6)alkyl, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted -S-aryl, and optionally substituted -S-heteroaryl; R2is selected from -Z1-*, -NHCOCH3, -NHCOCF3, -NHCOCH2CF3, -OH, -NHR, and optionally substituted triazole; Attorney Ref: 92VF-350823-WO Client Ref: 021WO R6is selected from -Z1-*, -OH, -OR, optionally substituted (C1-C6)alkyl, -OC(O)R, -C(O)NHR, -NRxxRyy, optionally substituted aryl, optionally substituted heteroaryl, -NHCOR, and -NRCOR; each R is independently optionally substituted (C1-C6)alkyl, optionally substituted aryl, or optionally substituted heteroaryl; Rxxand Ryyare independently H, optionally substituted (C1-C6)alkyl, or Rxxand Ryycan cyclize to form an optionally substituted heterocyclyl; wherein one of R1, R2, and R6is -Z1-*, and “ * ” represents a point of connection of Z1to the linker (L); R3and R4are each independently H, or a promoiety, or R3and R4are cyclically linked to form a promoiety; R11is H, or a bridging moiety that connects the 5-position carbon to the 1-position carbon of the ring; Z1is a linking moiety selected from -Z11-, -Z11-A1-*, -A2-, -NR21CO-*, - CONR21-*, -NR21SO2*-, -SO2NR21-*, -NR21C(=O)NR21-, and -NR21C(=S)NR21-; - - - - - - optionally substituted arylene, or each R21is independently selected from H, optionally substituted (C1-C6)alkyl, -COR, and optionally substituted heteroaryl; and each R22is independently selected from H, halogen, and optionally substituted (C1-C6)alkyl. In some embodiments, the lysosomal targeting bifunctional molecules of this disclosure (e.g., of Formula I) can include an ASGPR ligand moiety of Formula II: R66 II wherein: R1is selected from -Z1-*, -H, -OH, -CH3, -OCH3, and -OCH2CH=CH; R2is selected from -Z1-*, -NHCOCH3, -NHCOCF3, -NHCOCH2CF3, -OH, and optionally substituted triazole; R6is selected from -Z1-*, -OH, -OC(O)R, -C(O)NHR, and optionally substituted triazole, where R is optionally substituted (C1-C6)alkyl or optionally substituted aryl; Attorney Ref: 92VF-350823-WO Client Ref: 021WO wherein one of R1, R2, and R6is -Z1-*, and “ * ” represents a point of connection of Z1to the linker (L); R3and R4are each independently H, or a promoiety, or R3and R4are cyclically linked to form a promoiety; R11is H, or a bridging moiety that connects the 5-position carbon to the 1-position carbon of the ring; Z1is a linking moiety selected from -Z11-, -Z11-A1-*, -A2-, -NR21CO-*, - CONR21-*, -NR21SO2-*, -SO2NR21-*, -NR21C(=O)NR21-, and -NR21C(=S)NR21-; -Z11- is -O- -S- -N - or -C or optionally substituted heteroarylene; optionally substituted (C1-C6)alkyl; and each R22is independently selected from H, halogen (e.g., F) and optionally substituted (C1- C6)alkyl. In some embodiments, X is represented by Formula a-II: R66 In some embodiments, R1is - In some embod1 1 iments, R is -Z -*, -H, or n-propyl. In some embodiments, R2is -Z1-* or -NHCOCH3. In some embodiments, R3and R4are each -H. In some embodiments, L comprises of 10 to 60 consecutive branched or linear chain atoms. In some embodiments, L is of Formula: 5 wherein: n is 1, 2, or 3; each L1to L6is independently a linking moiety which together provide a linear or branched linker between Z1and Y; a, b, c, d, and e are each independently 1, 2, 3, 4, or 5; ** represents the point of attachment of X via Z1to L1; and Attorney Ref: 92VF-350823-WO Client Ref: 021WO *** represents the point of attachment to Y. In some embodiments, each L1to L5independently comprises one or more linking moieties independently selected from -C1-20-alkylene-, -NHC(O)-C1-6-alkylene-, -C(O)NH-C1-6-alkylene-, -NHC1-6-alkylene-, -NHC(O)NH-C1-6-alkylene-, -NHC(S)NH-C1-6-alkylene-, -C1-6-alkylene-NHC(O)-, -C1-6-alkylene-C(O)NH-, -C1-6-alkylene-NH-, -C1-6-alkylene-NHC(O)NH-, -C1-6-alkylene-NHC(S)NH-, -O(CH2)p-, -(OCH2CH2)p-, -NHC(O)-, -C(O)NH-, -NHS(O)2-, -S(O)2NH-, -C(O)-, -S(O)2-, -O-, -S-, monocyclic heteroaryl, monocyclic aryl, monocyclic heterocycle, monocyclic carbocycle, amino acidresidue, -NH-, and -NCH3-; wherein each L1to L5is independently optionally substituted with one to fivehalo; each p is independently1 to 50; L6is a linking group comprising one or more linking moieties independently selected from -C1-20-alkylene-, -NR16C(O)-C1-6-alkylene-, -C(O)NR16-C1-6-alkylene-, -NR16-C1-6-alkylene-, -NR16C(O)NR16-C1-6-alkylene-, -NR16C(S)NR16-C1-6-alkylene-, -C1-6-alkylene-NR16C(O)-, -C1-6-alkylene- C(O)NR16-, -C1-6-alkylene-NR16-, -C1-6-alkylene-NR16C(O)N R16-, -C1-6-alkylene-NR16C(S)NR16-, - O(CH2)p-, -(OCH2CH2)p-, -NR16C(O)-, -C(O)NR16-, -NHS(O)2-, -S(O)2NH-, -C(O)-, -S(O)2-, -O-, -S-, monocyclic heteroaryl, monocyclic aryl, monocyclic heterocycle, amino acid residue, or -NR16-; and each R16is independently -H, optionally substituted (C1-C6)alkyl, optionally substituted aryl, optionally substituted monocyclic heteroaryl or monocyclic heteroaryl. In some embodiments, each L1to L5is independently selected from -C1-20-alkylene-, -NHC(O)- C1-6-alkylene-, -C(O)NH-C1-6-alkylene-, -NH-C1-6-alkylene-, -NHC(O)NH-C1-6-alkylene-, -NHC(S)NH- C1-6-alkylene-, -C1-6-alkylene-NHC(O)-, -C1-6-alkylene-C( )NH-, -C1-6-alkylene-NH-, -C1-6-alkylene- NHC(O)NH-, -C1-6-alkylene-NHC(S)NH-, -O(CH2)p-, -(OCH2CH2)p-, -NHC(O)-, -C(O)NH-, -NHS(O)2-, -S(O)2NH-, -C(O)-, -S(O)2-, -O-, -S-, monocyclic heteroaryl, monocyclic aryl, monocyclic heterocycle, monocyclic carbocycle, amino acid residue, -NH-, and -NCH3-; wherein each L1to L5is independently optionally substituted with one to five halo; each p is independently1 to 50; and O *** Attorney Ref: 92VF-350823-WO Client Ref: 021WO z O O O O R S N N N z , In some embodiments, the ASGPR binding moiety (X) of the compounds of this disclosure can be described by Formula IIa: R6wherein R2, R3, R4, R6and Z1 embodiments of Formula IIa, R6is selected from -OH, -OC(O)R, and -C(O)NHR; and R2is selected from -NHCOCH3, -NHCOCF3, and -NHCOCH2CF3. In some embodiments of Formula II, Z1is in a beta configuration, and can be described by Formula IIa-1: Attorney Ref: 92VF-350823-WO Client Ref: 021WO R61. In some embodiments of and can be described by Formula IIa-2: R62. In some embodiments of is -Z11-A1-, whe1 rein A - is optionally substituted arylene or optionally substituted heteroarylene. In some embodiments, A1is an optionally substituted heteroarylene. In some embodiments, the heteroarylene is a 5 or 6-membered heteroarylene. In some embodiments, the heteroarylene is a 5-membered heteroarylene. In some embodiments, the 5- membered heteroarylene is a triazole. In some embodiments, the triazole is a 1,2,3-triazole moiety. In some embodiments, the ASGPR binding moiety (X) of the compounds of this disclosure can be described by Formula IIIa or IIIb: OH OH wherein: -Z11- is -O-, -S-, -N(R21)-, or -C(R22)2-, where each R22is independently selected from H, halogen (e.g., F) and optionally substituted (C1-C6)alkyl, and R21is H or optionally substituted (C1-C6)alkyl; and -A1- is arylene, substituted arylene, heteroarylene, or substituted heteroarylene. In some embodiments, -A1- is arylene or heteroarylene; wherein each is independently optionally substituted with one to three halo, C1-3alkyl, C1-3haloalkyl, C1-3alkoxy, or C1-3haloalkoxy. In some embodiments of Formula IIIa or IIIb, Z11is -S-. Attorney Ref: 92VF-350823-WO Client Ref: 021WO In some embodiments, Z11is -C(R22)2-. In some embodiments, Z11is -CH2-. In some embodiments, Z11is -C(R22)2, where at least one R22is H. In some embodiments, both R22are H. In some embodiments Z11is -O-. In some embodiments, Z11is -S-. In some embodiments cases, Z11is -N(R21), where R21is H or C1-3alkyl. In some embodiments, -A1- is triazole. In some embodiments, Z1is -C(R22)2-triazole-. In some N N** embodiments, Z1N N. In some embodiments, Z1N N. In some Formula IIa, IIa-1, or IIa-2, Z1 embodiments, Z11is - C(R22)2. In some embodiments, at least one R22is H. In some embodiments, both R22are H, and Z11is - CH2-. In some embodiments Z11is -O-. In some embodiments, Z11is -S-. In certain other cases, Z11is - N(R21), where R21is H or C1-3alkyl. In some embodiments of Formula IIa, IIa-1, or IIa-2, Z1is monocyclic 5 or 6-membered N N heteroaryl or aryl. In some embodiments, Z1. In some embodiments, N N. In some embodiments of Formula IIa-2, Z1is selected from - , ,2-, X1; X1is O or S; t is 0 or 1; R21and each R23is independently selected from H, and optionally substituted (C1-C6)alkyl (e.g., C(1-3)-alkyl, such as methyl); and each R22is independently selected from H, halogen (e.g., F) and optionally substituted (C1- C6)alkyl. In some embodiments of Formula IIa, IIa-1, or IIa-2, Z1is optionally substituted (C1-C6)alkyl. In some cases of Z1the alkyl is methyl. In some cases of Z1, the alkyl is ethyl. In some cases of Z1, the Attorney Ref: 92VF-350823-WO Client Ref: 021WO alkyl is propyl. In some cases of Z1, the alkyl is butyl. In some cases of Z1, the alkyl is pentyl. In some cases of Z1, the alkyl is hexyl. In some embodiments, the ASGPR binding moiety (X) of Formula IIa-1 is selected from one of the following structures: OH OH OH 3, IIIb-2: OH 2 wherein: -A1- is arylene, or substituted heteroarylene. In some embodiments of Formula IIIb-2, A1is a triazole. In some embodiments of Formula IIIb- 2, X is of Formula XA-4. In some embodiments of Formula IIa-1, Z1is in a beta configuration at the 1-position carbon of the galactosamine ring. In some embodiments of Formula IIa-1, Z1is S, and each X is of Formula XA-1. In some embodiments of Formula IIa-1, each X is of formula XA-2. In some embodiments of Formula IIa- 1, each X is of Formula XA-3. In some embodiments of Formula IIa-1, each X is of Formula XA-4. In some embodiments of Formula IIa-1, each X is of Formula XA-5. Attorney Ref: 92VF-350823-WO Client Ref: 021WO In some embodiments, the compound of Formula IIa-2 is selected from one of the following structures: OH OH OH HO 3, is of Formula IIIb-1: OH 1 wherein -A1- is arylene, substituted heteroarylene. In some embodiments of Formula IIIb-1, A1is an optionally substituted heteroarylene. In some embodiments, the heteroarylene is a 5 or 6-membered heteroarylene. In some embodiments, the heteroarylene is a 5-membered heteroarylene. In some embodiments, the 5-membered heteroarylene is a triazole. In some embodiments, the triazole is a 1,2,3-triazole moiety. In some embodiments, each is independently optionally substituted with one to three halo, C1-3alkyl, C1-3haloalkyl, C1-3alkoxy, or C1-3haloalkoxy. In some embodiments, the X of Formula IIIb-1 is selected from one of the following structures: Attorney Ref: 92VF-350823-WO Client Ref: 021WO OH OH 2 In R6R6is -OH, R2is -NHC(O)CH3, R3is4 1 R is H, and Z is -O-, -S-, -CH2-, -NH-, or a 1,2,3-triazolyl. In some embodiments, Z1is in the alpha configuration such that the ASGPR binding moiety is derived from Formula IIa-2: R62. 2-linked ASGPR ligand moieties In some embodiments, the ASGPR binding moiety (X) is linked via the 2-postion of the sugar analog. In some embodiments, the ASGPR binding moiety (X) has a reduced ring carbon at the 1- position relative to a galactosamine derived sugar. In some embodiments, the ASGPR binding moiety (X) of the bifunctional molecules of this disclosure is described by Formula IIb: R6herein R1, R3 w , R4, R6, R11, and Attorney Ref: 92VF-350823-WO Client Ref: 021WO In some embodiments, the ASGPR binding moiety (X) of the compounds of this disclosure are described by Formula IIb’: R6O IIb’ wherein R3-R4, R6, and Z1are as In some embodiments, the ASGPR binding moiety (X) of the compounds of this disclosure are described by Formula IVa: OH R11wherein R1, R11, and Z1are as In some embodiments of Formula IIb, IIb’, or IVa, Z1is selected from optionally substituted X1-(C(R22)2)q-h t, wherein t is 0 or 1.In some IIb’ or IVa, Z1is optionally substituted -(C(R22)2)q-triazole, wherein q is 0 or 1. In some embodiments of Formula IIb, IIb’ or IVa, Z1is -(C(R22)2)q-1,2,3-triazolyl, wherein q is 0 or 1. ∗ In some embodiments of Formula In some embodiments, Z1is ∗ N . Attorney Ref: 92VF-350823-WO Client Ref: 021WO O NNIn some embodiments of Formula IIb, IIb’ or IVa, Z1, wherein R23is H, orC(1-3)-alkyl. In some embodiments of Formula IIb, IIb’ or wherein R23is H or C(1-3)- alkyl. In some embodiments of Formula IIb, IIb’ or IVa, Z1is selected from -O-, -S-, -C(R22)2-, -NR21-, X1NN; X1is O or S; t is 0 or 1; R21and each R23is independently selected from H, and optionally substituted C1-6alkyl (e.g., C(1-3)-alkyl, such as methyl); and each R22is independently selected from H, halogen (e.g., F) and optionally substituted C1-6alkyl. In some embodiments, each is independently optionally substituted with one to three halo, C1-3alkyl, C1-3haloalkyl, C1-3alkoxy, or C1-3haloalkoxy. In some embodiments, each X is independently selected from: OR1AHO HO O 1A 1A HOO R O OR In some embodiments, the ASGPR binding moiety (X) of the compounds of this disclosure can be described by Formula IVb or IVc: Attorney Ref: 92VF-350823-WO Client Ref: 021WO OH OH R11R11HO HO wherein: -Z11- is -O-, -S-, -N(R21)-, or -C(R22)2; -A1- and -A2- are optionally substituted arylene or optionally substituted heteroarylene; each R21is independently selected from H, and optionally substituted (C1-C6)alkyl; and each R22is independently selected from H, halogen (e.g., F) and optionally substituted (C1- C6)alkyl. In some embodiments of Formula IVb or IVc, R1is H. O O ∗ , embodiments, both R22are H. In some embodiments, Z11is -O-. In some embodiments, Z11is -S-. In some embodiments, Z11is -N(R21), where R21is H or (C1-C3)alkyl. In some embodiments of Formula IVb, IVc, IVb-1, or IVc-1, -A1- and -A2- are each independently an optionally substituted heteroarylene. In some embodiments, the heteroarylene is a 5 or 6-membered heteroarylene. In some embodiments, the heteroarylene is a 5-membered heteroarylene. In some embodiments, the heteroarylene is a 6-membered heteroarylene. In some embodiments of Formula IVb, or IVb-1, the A1ring is a 5-membered heteroarylene selected from triazole, thiadiazole, thiophene, oxazole, isoxazole, isothiazole, thiazole, oxadiazole, and furan. In some embodiments, the A1ring is a 6-membered heteroarylene selected from pyridine, pyrimidine, pyridazine, pyrazine, and triazine. In some embodiments, the A1ring is triazole. In some embodiments, the A1ring is pyridine. In some embodiments, the A1ring is pyrimidine. In some Attorney Ref: 92VF-350823-WO Client Ref: 021WO embodiments, the A1ring is thiadiazole. In some embodiments, the A1ring is a 5 or 6-membered arylene or heteroarylene that is further substituted with one or more substituents. In some cases, the A1ring is further substituted with one or more substituents selected from halogen, (C1-C6)alkyl and substituted (C1-C6)alkyl (e.g., CF3). In some embodiments, the A2ring is a 5-membered heteroarylene selected from triazole, thiadiazole, thiophene, oxazole, isoxazole, isothiazole, thiazole, oxadiazole, and furan. In some embodiments, the A2ring is a 6-membered heteroarylene selected from pyridine, pyrimidine, pyridazine, pyrazine, and triazine. In some embodiments, the A2ring is triazole. In some embodiments, the A2ring is pyridine. In some embodiments, the A2ring is pyrimidine. In some embodiments, the A2ring is thiadiazole. In some embodiments, the A2ring is a 5 or 6-membered arylene or heteroarylene that is further substituted with one or more substituents. In some cases, the A2ring is further substituted with one or more substituents selected from halogen, (C1-C6)alkyl and substituted (C1-C6)alkyl (e.g., CF3). In some embodiments, -Z11-A1- is a monocyclic 5 or 6-memebered heteroarylene of one of the following structures: H N N NNN N , N . to connect a particular -Z11-A1- group to an adjacent linker. Attorney Ref: 92VF-350823-WO Client Ref: 021WO In some embodiments of Formula IIb, or IVa-IVc, R1is H, such that the compound of Formula IIb, or IVa-IVc has no non-hydrogen substituents at the 1-position of the sugar ring. In some embodiments, the compound of Formula IIb is of any one of Formula IVd-IVg: R6OR11 R6OR11O O R21wherein In some embodiments of any one of Formula IVd-IVg, the A1ring is a 5 or 6-membered arylene or heteroarylene. In some embodiments, the A1ring is a 5-membered heteroarylene selected from triazole, thiadiazole, thiophene, oxazole, isoxazole, isothiazole, thiazole, oxadiazole, and furan. In some embodiments, the A1ring is a 6-membered heteroarylene selected from pyridine, pyrimidine, pyridazine, pyrazine, and triazine. In some embodiments, the A1ring is triazole. In some embodiments, the A1ring is pyridine. In some embodiments, the A1ring is pyrimidine. In some embodiments, the A1ring is thiadiazole. In some embodiments, the A1ring is a 5 or 6-membered arylene or heteroarylene that is further substituted with one or more substituents. In some cases, the A1ring is further substituted with one or more substituents selected from halogen, (C1-C6)alkyl and substituted (C1-C6)alkyl (e.g., CF3). In some embodiments of any one of Formula IVd-IVg, the A2ring is a 5 or 6-membered arylene or heteroarylene. In some embodiments, the A2ring is a 5-membered heteroarylene selected from triazole, thiadiazole, thiophene, oxazole, isoxazole, isothiazole, thiazole, oxadiazole, and furan. In some embodiments, the A2ring is a 6-membered heteroarylene selected from pyridine, pyrimidine, pyridazine, pyrazine, and triazine. In some embodiments, the A2ring is triazole. In some embodiments, the A2ring is pyridine. In some embodiments, the A2ring is pyrimidine. In some embodiments, the A2ring is thiadiazole. In some embodiments, the A2ring is a 5 or 6-membered arylene or heteroarylene that is further substituted with one or more substituents. In some cases, the A2ring is further substituted with one or more substituents selected from halogen, (C1-C6)alkyl and substituted (C1-C6)alkyl (e.g., CF3). In some embodiments of any one of Formula IVd-IVg, the A1or A2ring is absent. Attorney Ref: 92VF-350823-WO Client Ref: 021WO In some embodiments of any one of Formula IVd-IVg, the A1or A2ring is phenylene or substituted phenylene. In some embodiments of Formula IVd, the A2ring is a 5 or 6-membered heteroarylene. In some embodiments of Formula IVd, the A2ring is a 5-membered heteroarylene. In some embodiments of Formula IVd, the A2ring is triazole. In some embodiments of Formula IVd, the A2ring is absent. In some embodiments of Formula IVe, the A1ring is a 5 or 6-membered heteroarylene and R21is H. In some embodiments of Formula IVe, the A ring is triazole. In some embodiments of Formula IVe,the A1ring is pyridine. In some embodiments of Formula IVe, the A1ring is pyrimidine. In someembodiments of Formula IVe, the A1ring is thiadiazole. In some embodiments of Formula IVe, the A1ring is absent and R21is H or optionally substituted acyl. In some cases, R21is -COCH3. In some cases, R21is H. In some embodiments of Formula IVf, the A1ring is a 5 or 6-membered heteroarylene. In some embodiments of Formula IVf, the A1ring is a 5-membered heteroarylene. In some embodiments of Formula IVf, the A1ring is triazole. In some embodiments of Formula IVf, the A1ring is absent. In some embodiments of Formula IVg, the A2ring is a 5 or 6-membered heteroarylene. In some embodiments of Formula IVg, the A2ring is a 5-membered heteroarylene. In some embodiments of Formula IVg, the A2ring is triazole. In some embodiments of Formula IVg, the A2ring is absent. In some embodiments, the ASGPR binding moiety (X) of the compounds of this disclosure can be described by any one of Formula IVl-IVm: R6O Y5 *O * wherein: R6, R4, R3, and R21are as defined herein; Y1-Y3are each independently N or CR25; Y4is N or CR24; Y5is S, O, or NH; and R24and R25are each independently selected from H, optionally substituted C(1-6)-alkyl, optionally substituted fluoroalkyl, and halogen. Attorney Ref: 92VF-350823-WO Client Ref: 021WO In some embodiments of Formula IVi at least one of Y1to Y3is N. In some cases, at least two of Y1to Y3are N. In some embodiments, Y1and Y3are N and Y2is CR25. In some embodiments, Y1and Y2are N and Y3is CR25. In some embodiments, Y1and Y2are CR25and Y3is N. In some embodiments of any one of formulae IVd-IVk R6is H. In some embodiments of any one of Formula IVd-IVk, R4and R3are each H. In some embodiments, at least one of R4-R3is a promoiety. In some embodiments, R4and R3are cyclically linked to form a promoiety (e.g., as described herein). In some embodiments, X is of Formula IVi-1: OH 1) wherein R24and R25are C1-6-alkyl and substituted C1-6-alkyl (e.g., CF3). In some embodiments of Formula IVi - IVi-1, R25is H. In some embodiments, R25is C1-3-alkyl, or C(1-3)-fluoroalkyl. In some cases, the fluoroalkyl is -CF3. In some embodiments of Formula IVi or IVi- 1, R24is H. In some embodiments, R24is C1-3-alkyl, or C1-3-fluoroalkyl. In some cases, the fluoroalkyl is -CF3. In some embodiments, X is of Formula XD1: OH In some embodiments, X is of Attorney Ref: 92VF-350823-WO Client Ref: 021WO OH HO In some embodiments, X is of OH In some embodiments, X is of R6OO * 1 wherein: R6, R4, R3, and R21are as defined herein; Y1-Y4are each independently N or CR25; Y5is S, O, or NH; and each R25is independently selected from H, optionally substituted C(1-6)-alkyl, optionally substituted fluoroalkyl, and halogen. In some embodiments, each R25is H. In some embodiments, the ASGPR binding moiety (X) of the compounds of this disclosure can be described by one of the following structures: Attorney Ref: 92VF-350823-WO Client Ref: 021WO OH OH O O * . In some of this disclosure can be described by one of the HOHOOHHO * OH wherein Z1is -NH-, -CH2-, -S- or -O-. Attorney Ref: 92VF-350823-WO Client Ref: 021WO 6-linked ASGPR ligand moieties In some embodiments, the ASGPR binding moiety (X) is linked via the 6-postion of the sugar analog. In some embodiments, the ASGPR binding moiety (X) has a reduced ring carbon at the 1- position relative to a galactosamine derived sugar. In some embodiments, the ASGPR binding moiety (X) of the compounds of this disclosure can be described by Formula IIc: Z1* R11wherein R1-R4and Z1are as In some embodiments of Formula IIc, Z1is selected from -O-, -S-, -CONR21-, and optionally substituted -(C(R22)2)q- heteroarylene, wherein q is 0 or 1. In some embodiments, Z1is -O-. In certain other cases, Z1is optionally substituted -(C(R22)2)q-triazole wherein q is 0 or 1. In some . In some Z1is -Z11-A1-, wherein -A1- is or optionally substituted - A1- or optionally substituted arylene. In some embodiments, -A1- is an optionally substituted heteroarylene. In some embodiments, the heteroarylene is a 5 or 6-membered heteroarylene. In some embodiments, the heteroarylene is a 5-membered heteroarylene. In some embodiments, the 5-membered heteroarylene is a triazole. In some embodiments, the triazole is a 1,2,3-triazole moiety. In some embodiments, Z11is -C(R22)2. In some embodiments, at least one R22is H. In some embodiments, both R22are H. In some embodiments Z11is -O-. In some embodiments, Z11is -S-. In certain other cases, Z11is -N(R21), where R21is H or C1-3alkyl. In some embodiments, Z1is -C(R22)2-triazole-. * In some . In some Z11. In some embodiments, Z11is -C(R22)2. In some embodiments, at least one R22is H. In some embodiments, both R22are H, and Z11is -CH2-. In some Attorney Ref: 92VF-350823-WO Client Ref: 021WO embodiments Z11is -O-. In some embodiments, Z11is -S-. In certain other cases, Z11is -N(R21), where R21is H or (C1-C3)alkyl. In some embodiments of Formula IIc, Z1is monocyclic 5 or 6-membered heteroarylene or arylene. In some . In some embodiments Z1is selected fr22 21 om -O-, -S-, -C(R )2-, -N(R ) X1NN; X1is O or S; t is 0 or 1; R21and each R23is independently selected from H, and optionally substituted C1-6alkyl (e.g., C1-3- alkyl, such as methyl); and each R22is independently selected from H, halogen (e.g., F) and optionally substituted C1-6alkyl. O In some embodiments, the compound of Formula. O N In some embodiments, the compound of Formula . 2 In some embodiments, R is: Attorney Ref: 92VF-350823-WO Client Ref: 021WO HN NHNN CF3HNN CF3. of the compounds of this disclosure can be Z1∗ R111 wherein: R1is -H, -OH, optionally substituted (C1-C6)alkyl, or -OCH3, and R11is hydrogen; or R1and R11together with the carbon atoms to which each is attached form a bridging moiety; Z1is a linking moiety selected from -Z11-, -Z11-A1-*, -A2-, -NR21CO-*, - CONR21-*, -NR21SO2*-, -SO2NR21-*, -NR21C(=O)NR21-, and -NR21C(=S)NR21-; where “ * ” represents a point of connection of Z1to the linker (L); -Z11- is -O-, -S-, -N(R21)-, or -C(R22)2; -A1- and -A2- are optionally substituted heterocyclylene, optionally substituted arylene, or optionally substituted heteroarylene; each R21is independently selected from H, optionally substituted (C1-C6)alkyl, -COR, and optionally substituted heteroaryl; and each R22is independently selected from H, halogen, and optionally substituted (C1-C6)alkyl. In some embodiments, the ASGPR ligand moiety (X) of the compounds of this disclosure can be described by Formula IIc-2: Attorney Ref: 92VF-350823-WO Client Ref: 021WO Z1∗ R11HO 2 wherein: R1is -H, -OH, optionally substituted (C1-C6)alkyl, or -OCH3, and R11is hydrogen; or R1and R11together with the carbon atoms to which each is attached form a bridging moiety; Z1is a linking moiety selected from -Z11-, -Z11-A1-*, -A2-, -NR21CO-*, - CONR21-*, -NR21SO2*-, -SO2NR21-*, -NR21C(=O)NR21-, and -NR21C(=S)NR21-; where “ * ” represents a point of connection of Z1to the linker (L); -Z11- is -O-, -S-, -N(R21)-, or -C(R22)2; -A1- and -A2- are optionally substituted heterocyclylene, optionally substituted arylene, or optionally substituted heteroarylene; each R21is independently selected from H, optionally substituted (C1-C6)alkyl, -COR, and optionally substituted heteroaryl; and each R22is independently selected from H, halogen, and optionally substituted (C1-C6)alkyl. In some embodiments, the ASGPR ligand moiety (X) of the compounds of this disclosure can be described by Formula IIc-1A: Z1∗ In some embodiments, the compounds of this disclosure can be described by Formula IIc-2A: Attorney Ref: 92VF-350823-WO Client Ref: 021WO O ∗ HO In some embodiments, the compounds of this disclosure can be described by Formula a-IIc-1, a-IIc-2, a-IIc-1A, or a-IIc-2A: Z1∗ ∗ 1 ∗ Z1Z R11R111A can be described by Formula IId: R6wherein: R6, R4, R3, and Z1are as defined herein; Y6and Y5are each independently selected from -O-, -S-, NR21-, and -C(R22)2; R21is selected from H, optionally substituted C1-6alkyl, and -C(O)R22; Attorney Ref: 92VF-350823-WO Client Ref: 021WO each R22is independently selected from H, halogen and optionally substituted C1-6alkyl; and ring B is a 5 or 6-membered optionally substituted cyclic group. In some embodiments of Formula IId, Y5is connected to the sugar ring via an alpha configuration. In some embodiments of Formula IId, Y5is connected to the sugar ring via a beta configuration. In some embodiments, the ASGPR binding moiety (X) of the compounds of this disclosure can be described by Formula IId’: R6wherein: R6, R4, R3, and Z1are as defined herein; Y5and Y6are each independently selected from -O-, -S-, NR21-, and -C(R22)2; R21is selected from H, optionally substituted (C1-C6)alkyl, and -C(O)R22; each R22is independently selected from H, halogen and optionally substituted (C1-C6)alkyl; and ring B is a 5 or 6-membered optionally substituted cyclic group. In some embodiments of Formula IId-IId’, Y5is O. In some embodiments, Y5is S. In some embodiments, Y5is -NR21-. In some embodiments, Y5is -C(R22)2and each R22is H. In some embodiments of Formula IId-IId’, Y6is -NR21- where R21is H. In some embodiments, Y6is -NR21- where R21is -C(O)R22. In some cases, R22is methyl. In some embodiments of Formula IId-IId’, the B ring is a 5 or 6-membered heterocycle. In some cases, the B ring is a 5-membered heterocycle. In some cases, the B ring is a 6-membered heterocycle. In some embodiments of Formula IId-IId’, Z1is Z11, where Z11is selected from -O-, -S-, NR21-, and -C(R22)2. In some cases, Z1is -O-. In some cases, Z1is -S-. In some cases, Z1is NR21where R21is H. In some cases, Z1is -C(R22)2where each R22is H. In some embodiments of Formula IId-IId’, Z1is optionally substituted Z11-heteroarylene or optionally substituted Z11-arylene. In some embodiments, Z1is CH2-heteroarylene or CH2-arylene. In some embodiments of Formula IId-IId’, Z1is optionally substituted amide. In some embodiments of Attorney Ref: 92VF-350823-WO Client Ref: 021WO Formula IId-IId’, Z1is optionally substituted sulfonamide. In some embodiments of Formula IId-IId’, Z1is optionally substituted urea or optionally substituted thiourea. In some embodiments, X has one of the following structures: OH OH HO HO . In some o6 ther cases, R is -OC(O)R. In some embodiments, R6is -C(O)NHR, where R is an optionally substituted alkyl. In some embodiments, R terminates in an alkenyl or an alkynyl group. In certain other cases R6is optionally substituted triazole. HO N In some embodiments, the triazoleN. In some embodiments of Formula In some embodiments, R2is - NHCOCF3. In certain other embodiments, R2is -NHCOCH2CF3. In some embodiments, R2is -OH. In some embodiments, R2is an optionally substituted triazole. O N In some embodiments, the triazole.In some embodiments, when R6or triazole is a 1,2,3-trizole, and the substituent is at the 4 or 5-position. In some embodiments, the substituent on the triazole moiety includes but is not limited to, an optionally substituted C1-6alkyl, optionally substituted C1-6alkoxy, optionally substituted aryl, optionally substituted heteroaryl, optionally substituted alkaryl, and an optionally substituted alkyheteroaryl. It will be understood that any convenient substituent can be included in the triazole moiety, see, e.g., triazole moieties disclosed in Mamidayala et al, J. Am. Chem. Soc.2012, 134, 1978-1981. It is understood that the Z1, Z11, and Z11-Ar linking moieties can be considered part of the X group of Formula I. In the ASGPR binding moieties (X) as described herein, -Z1- can be linked to an -L1- moiety (e.g., of the linker as described herein) via a variety of bonds and linking moieties, depending on the method of preparation. Attorney Ref: 92VF-350823-WO Client Ref: 021WO In some embodiments, the subject compounds comprise a -Z1-L1- moiety selected from: R22R22O O o O O S r , each R22is independently selected from H, halogen (e.g., F) and optionally substituted (C1-C6)alkyl; and o, p, q, r, s, t, u, v, w, x, y, z and z1 are each independently 1 to 6. In some embodiments, o, p, q, r, s, t, u, v, w, x, y, z and z1 are each independently 1 to 6. In some embodiments, the subject compounds comprise a -Z1-L- group selected from: O O O O . In some embodiments, the Z1-L1- group , where q is 1-3. In someembodiments, q is 1. In some embodiments, q is q is 3. Attorney Ref: 92VF-350823-WO Client Ref: 021WO O N In some embodiments, the Z1-L1- group . In some embodiments, the Z1-L1- group is. S 11NIn some embodiments, the Z -L - group . In some embodiments, -Z1-L1- -NH-heteroarylene-. In some embodiments the heteroarylene is a triazole. In some embodiments, the heteroarylene is pyridine. In some embodiments, the heteroarylene is pyrimidine. In some embodiments, the heteroarylene is thiadiazole. In some embodiments, the -Z1-L1- comprises a group selected from: O R21, optionally substituted acyl; and R24and R25are each independently selected from H, optionally substituted C(1-6)-alkyl, optionally substituted fluoroalkyl, and halogen. In some embodiments, the -Z1-L1- comprises a group selected from: R21O R21; selected from H, optionally substituted C(1-6)-alkyl, optionally substituted fluoroalkyl, and halogen; and each R21is independently selected from H, optionally Attorney Ref: 92VF-350823-WO Client Ref: 021WO substituted (C1-C6)alkyl, and optionally substituted acyl. In some embodiments, R21is H. In some embodiments, R24is C(1-3)-alkyl, or C(1-3)-fluoroalkyl. In some cases, the fluoroalkyl is CF3. In some embodiments, R25is C(1-3)-alkyl, or C(1-3)-fluoroalkyl. In some cases, the fluoroalkyl is CF3. N In some e . It is understood that a can be utilized to connect a particular X ligand moiety (e.g., as described herein) to an adjacent linker. In some embodiments, a linking moiety of the linker comprises a triazole that derives from a Click chemistry conjugation. In some embodiments, the ASGPR ligand moiety (X) is attached to a linking moiety as shown in one of the following structures: HO ONNN* , Attorney Ref: 92VF-350823-WO Client Ref: 021WO OH HO O O NN S *. In some OH wherein Z1is triazole, -NH- - attached to pyridine or pyrimidine), -NH-, -O-, or -CH2- , and / or Z1is attached to a linking moiety as shown in one of the following structures: O N O N , Attorney Ref: 92VF-350823-WO Client Ref: 021WO In some embodiments, of Formula Iib, R1R3, R4, and R11are H, and R6is OH: OH HO wherein Z1is attached to a linking one of the following structures: O O N N . 1.1.2 Aspects of this disclosure include prodrugs of any of the ASGPR ligand moieties described herein that are incorporated into the linker compounds and conjugates of this disclosure. The term “prodrug” refers to an agent which is converted into the drug in vivo by some physiological or chemical process (e.g., a prodrug on being brought to the physiological pH is converted to the desired drug form). Prodrugs forms of any of the ASGPR ligand moieties described herein can be useful because, for example, can lead to particular therapeutic benefits as a consequence of an extension of the half-life of the resulting compound or conjugate in the body or a reduction in the active dose required. Prodrugs can also be useful in some situations, as they may be easier to administer than the parent drug. They may, for instance, be bioavailable by oral administration whereas the parent drug is not. The prodrug may also have improved solubility in pharmacological compositions over the parent drug. A prodrug derivative of a ASGPR ligand moiety generally includes a labile promoiety substituent at a suitable site of the moiety. The promoiety refers to the group that is removed by enzymatic or chemical reactions, when a prodrug is converted to the drug in vivo. In some embodiments, the promoiety is a group, such as an optionally substituted alkanoyl, attached via an ester linkage to a hydroxyl group of the moiety. In some embodiments, a prodrug derivative of one or more of the hydroxyl groups of the sugar ring of the ASGPR ligand moiety may be incorporated into the compounds. For example, an ester promoiety can be incorporated at one or more of the hydroxyl groups at the 3 and / or 4 positions of the core sugar ring (e.g., as described in Formula (II)). Attorney Ref: 92VF-350823-WO Client Ref: 021WO In some embodiments, the hydroxyl groups at the 3 and 4 positions of the core sugar ring are cyclically linked to form a promoiety (e.g., as described herein). In some embodiments, the promoiety is the part of an ester group attached to a hydroxyl of X, such as -C(O)CH3, -C(O)CH(CH3)2, -C(O)C(CH3)3, or -CH2OC(O)C(CH3)3. In some embodiments, the promoiety is -CH2OC(O)C(CH3)3. In some embodiments, a promoiety cyclically links two adjacent hydroxyl groups via a carbonate linkage, i.e., a cyclic carbonate. 1.1.3 Linker The terms “linker,” “linking moiety,” and “linking group” are used interchangeably and refer to a linking moiety that covalently connects two or more moieties or compounds, such as ligands and other moieties of interest. In some cases, the linker is divalent and connects two moieties. In some embodiments, the linker is a branched linking group that is trivalent or of a higher multivalency. In some cases, the linker that connects the two or more moieties has a linear or branched backbone of 500 atoms or less (such as 400 atoms or less, 300 atoms or less, 200 atoms or less, 100 atoms or less, 80 atoms or less, 60 atoms or less, 50 atoms or less, 40 atoms or less, 30 atoms or less, or even 20 atoms or less) in length, e.g., as measured between the two or more moieties. A linking moiety may be a covalent bond that connects two groups or a linear or branched chain of between 1 and 500 atoms in length, for example of about 1, 2, 3, 4, 5, 6, 8, 10, 12, 14, 16, 18, 20, 30, 40, 50, 100, 150, 200, 300, 400 or 500 atoms in length, where the linker may be linear, branched, cyclic or a single atom. In some embodiments, one, two, three, four, five or more, ten or more, or even more carbon atoms of a linker backbone may be optionally substituted with heteroatoms, e.g., sulfur, nitrogen or oxygen heteroatom. In certain instances, when the linker includes a PEG group, every third atom of that segment of the linker backbone is substituted with an oxygen. The bonds between backbone atoms may be saturated or unsaturated, usually not more than one, two, or three unsaturated bonds will be present in a linker backbone. The linker may include one or more substituent groups, for example an alkyl, aryl or alkenyl group. A linker may include, without limitations, one or more of the following: oligo(ethylene glycol), ether, thioether, disulfide, amide, carbonate, carbamate, tertiary amine, alkyl which may be straight or branched, e.g., methyl, ethyl, n- propyl, 1-methylethyl (iso-propyl), n-butyl, n-pentyl, 1,1-dimethylethyl (t-butyl), and the like. The linker backbone may include a cyclic group, for example, an aryl, a heterocycle, a cycloalkyl group or a heterocycle group, where 2 or more atoms, e.g., 2, 3, or 4 atoms, of the cyclic group are included in the backbone. In some embodiments, a “linker” or “linking moiety” is derived from a molecule with two reactive termini, one for conjugation to a moiety of interest (Y), e.g., a biomolecule (e.g., an antibody) and the other for conjugation to a moiety (noted as X) that binds to a ASGPR cell surface receptor. When Attorney Ref: 92VF-350823-WO Client Ref: 021WO Y is a polypeptide, the polypeptide conjugation reactive terminus of the linker is in some cases a site that is capable of conjugation to the polypeptide through a cysteine thiol or lysine amine group on the polypeptide, and so is can be a thiol-reactive group such as a maleimide or a dibromomaleimide, or as defined herein, or an amine-reactive group such as an active ester (e.g., perfluorophenyl ester or tetrafluorophenyl ester), or as defined herein. In some embodiments of the formula described herein, the linker (i.e., L1-L6) comprises one or more straight or branched-chain carbon moieties and / or polyether (e.g., ethylene glycol) moieties (e.g.,repeating units of -CH2CH2O-), and combinations thereof. In some embodiments, these linkers optionallyhave amide linkages, urea or thiourea linkages, carbamate linkages, ester linkages, amino linkages, ether linkages, thioether linkages, sulfhydryl linkages, heteroaryl linkages, or other hetero functional linkages. In some embodiments, the linker comprises one or more of carbon atoms, nitrogen atoms, sulfur atoms, oxygen atoms, and combinations thereof. In some embodiments, the linker comprises one or more of an ether bond, thioether bond, amine bond, amide bond, carbon-carbon bond, carbon-nitrogen bond, carbon- oxygen bond, carbon-sulfur bond, and combinations thereof. In some embodiments, the linker comprises a linear structure. In some embodiments, the linker comprises a branched structure. In some embodiments, the linker comprises a cyclic structure. In some embodiments, the linker comprises one or more heteroaryl cyclic structures, e.g., a triazole, such as a 1,2,3-traizole. In some embodiments, the linker (i.e., L1-L6) separates X and the Y-B complex by a chain of 4 to 500 consecutive atoms. In some embodiments, the linker (i.e., L1-L6) separates X and the Y-B complex by a chain of 4 to 50 consecutive atoms. In some embodiments, linker separates X and the Y-B complex by a chain of 6 to 50 consecutive atoms, by a chain of 11 to 50 consecutive atoms, by a chain of 16 to 50 consecutive atoms, by a chain of 21 to 50 consecutive atoms, by a chain of 26 to 50 consecutive atoms, by a chain of 31 to 50 consecutive atoms, by a chain of 36 to 50 consecutive atoms, by a chain of 41 to 50 consecutive atoms, or by a chain of 46 to 50 consecutive atoms. In some embodiments, the linker (i.e., L1-L6) separates X and the Y-B complex by a chain of 6 to 50 consecutive atoms. In some embodiments, the linker (i.e., L1-L6) separates X and the Y-B complex by a chain of 11 to 50 consecutive atoms. In some embodiments, the linker (i.e., L1-L6) separates X and the Y-B complex by a chain of 16 to 50 consecutive atoms. In some embodiments, the linker (i.e., L1-L6) separates X and the Y-B complex by a chain of 21 to 50 consecutive atoms. In some embodiments, the linker (i.e., L1-L6) separates X and the Y- B complex by a chain of 26 to 50 consecutive atoms. In some embodiments, the linker (i.e., L1-L6) separates X and the Y-B complex by a chain of 31 to 50 consecutive atoms. In some embodiments, the linker (i.e., L1-L6) separates X and the Y-B complex by a chain of 36 to 50 consecutive atoms. In some embodiments, the linker (i.e., L1-L6) separates X and the Y-B complex by a chain of 41 to 50 consecutive Attorney Ref: 92VF-350823-WO Client Ref: 021WO atoms. In some embodiments, the linker (i.e., L1-L6) separates X and the Y-B complex by a chain of 46 to 50 consecutive atoms. In some embodiments, the linker (i.e., L1-L6) is a chain of 5 to 500 consecutive atoms separating X and the Y-B complex and which comprises an optionally substituted arylene linked to X, optionally substituted heteroarylene linked to X, optionally substituted alkylene linked to X, or heteroatom linked to X. In some embodiments, the linker (i.e., L1-L6) is a chain of 7 to 500 consecutive atoms separating X and the Y-B complex and which comprises an optionally substituted arylene linked to X, optionally substituted heteroarylene linked to X, optionally substituted alkylene linked to X, or heteroatom linked to X. In some embodiments, the linker (i.e., L1-L6) is a chain of 10 to 500 consecutive atoms separating X and the Y-B complex and which comprises an optionally substituted arylene linked to X, optionally substituted heteroarylene linked to X, optionally substituted alkylene linked to X, or heteroatom linked to X. In some embodiments, the linker (i.e., L1-L6) is a chain of 15 to 400 consecutive atoms separating X and Y and which comprises an optionally substituted arylene linked to X, optionally substituted heteroarylene linked to X, optionally substituted alkylene linked to X, or heteroatom linked to X. In some embodiments, the linker (i.e., L1-L6) is a chain of 16 to 400 consecutive atoms separating X and Y (or Z) and which comprises an optionally substituted arylene linked to X, optionally substituted heteroarylene linked to X, optionally substituted alkylene linked to X, or a heteroatom linked to X. In some embodiments, L is of Formula XII: ** ***wherein each L1to L5is independently a linking moiety which together provide a linear or branched linker between Z1and Y; a, b, c, d, and e are each independently 0, 1, or 2; ** represents the point of attachment of L1to X via Z1; and *** represents the point of attachment to the Y-B complex; wherein: when n is 1, a is 1, and c is 0; and Attorney Ref: 92VF-350823-WO Client Ref: 021WO when n is >1, a is 1, and c is 1. It is understood that the linker may be considered as connecting directly to a Z1group of a ASGPR binding moiety (X) (e.g., as described herein). In some embodiments of any of Formula Ia-Ip, the linker may be considered as connecting directly to the Z1group. Alternatively, the -Z1-L1- group (e.g., as described herein) can be considered part of a linking moiety that connects L to Y. The disclosure is meant to include all such configurations of ASGPR binding moiety (X) and linker (L). In some embodiments of Formula XII, the linking moiety L1includes a linear backbone of 6 to 40 consecutive atoms, such as 10 to 40, 10 to 30, 16 to 30, or 20 to 30 consecutive atoms. In some embodiments of Formula XII, the linking moiety L1includes a linear backbone of each L1comprises a linear backbone of 6 to 20 consecutive atoms, such as 6 to 16 consecutive atoms, such as 8, 9, 10, 11, 12, 13, 14, 15 or 16 consecutive atoms. In some embodiments, the linking moiety of Formula XII includes one or repeating ethylene glycol moieties (e.g., -CH2CH2O- or -OCH2CH2-). In some embodiments, the linking moiety of Formula XII includes 1 to 10 ethylene glycol moieties, such as 1, 2, 3, 4, 5 or 6 ethylene glycol moieties. In some embodiments, the linking moiety of Formula XII includes one or more triazole (e.g., 1,2,3-triazole) containing linking moieties. It is understood that the triazole may be derived from an azido-alkyne click chemistry and thus have two possible orientations depending on the method of synthesis: NNNNN . In some embodiments, the is: NNNN Nwherein w1 and u1 are 6. In some embodiments of the linker of Formula XII, d is 1 and the linking moiety L4is selected from one of Formula L2A-L2D: Attorney Ref: 92VF-350823-WO Client Ref: 021WO Z2x Z3x C each Z2and Z3is independently absent or selected from -NHCO-, -CONH-, -CO-, -O-, -NH-, and -NCH3-; x is 1 to 12 (e.g., 1 to 6, or 1 to 3); and y is 0 to 12 (e.g., 1 to 6, or 1 to 3). In some embodiments of any one of Formula L2A-L2D, Z2is -NHCO-. In some embodiments of any one of Formula L2A-L2D, Z2is -CONH-. In some embodiments of any one of Formula L2A- L2D, Z2is -CO-. In some embodiments of any one of Formula L2A-L2D, Z2is -O-. In some embodiments of any one of Formula L2A-L2D, Z2is -NH-. In some embodiments of any one of Formula L2A-L2D, Z2is -NCH3-. In some embodiments of any one of Formula L2A-L2D, Z2is absent. In some embodiments of any one of Formula L2A-L2D, Z3is -NHCO-. In some embodiments of any one of Formula L2A-L2D, Z3is -CONH-. In some embodiments of any one of Formula L2A- L2D, Z3is -CO-. In some embodiments of any one of Formula L2A-L2D, Z3is -O-. In some embodiments of any one of Formula L2A-L2D, Z3is -NH-. In some embodiments of any one of Formula L2A-L2D, Z3is - NCH3-. In some embodiments of any one of Formula L2A-L2D, Z3is absent. In some embodiments of Formula L2A, Z2is -O-, y is 0, and the linking moiety is of Formula L2Ai: O In some embodiments of Formula - - , and the linking moiety is of Formula L2Bi or L2Bii: Attorney Ref: 92VF-350823-WO Client Ref: 021WO O O x x N In some embodiments -NH-, and the linking moiety is of Formula L2Ci, L2Cii, L2Ciii, or L2Civ: NH x x HN x y In some embodiments, of any one of Formula L2A- L2Civ, x is 1 to 6. In some embodiments, x is 1 to 3. In some embodiments, x is 1. In some cases, x is 2. In some embodiments, x is 3. In some embodiments of Formula L2D, Z2is absent and the linking moiety is Formula L2Di: y N In some embodiments of any one of y is 0 to 6. In some embodiments, y is 0 to 3. In some embodiments, y is 0. In some embodiments, y is 1. In some embodiments, y is 2. In some embodiments, y is 3. In some embodiments of Formula XII, d is 1 and the linking moiety L4is selected from: O . In some Attorney Ref: 92VF-350823-WO Client Ref: 021WO O wherein: r is 1 or 2; and when n is 2, r is 1, when n is 3, r is 2. In some embodiments of the linker of formula (XI), b is 1 and the linking moiety L2is Formula Xva or XVb: O wherein: r is 1 or 2; and when n is 2, r is 1, when n is 3, r is 2. In some embodiments L2is of Formula XIIIa or XIIIb and L2includes two 2 or more amino acid residues (e.g., 3 or more, or 4 or more amino acid residues, linear or dendrimer). In some embodiments, L2includes 4 or more amino acid residues that are branched linking moieties selected from Lys, Orn, Asp, Glu, Ser, and Cys (e.g., where the sidechain, amino and carboxylic acid are each linked to an adjacent moiety). In some embodiments, the linking moiety of Formula XVI includes a linear backbone of 6 to 40 consecutive atoms, such as 10 to 40, 10 to 30, or 20 to 30 consecutive atoms. In some embodiments, the linking moiety of Formula XVI includes repeating ethylene glycol moieties (e.g., -CH2CH2O- or -OCH2CH2-). In some embodiments, the linking moiety of Formula XVI includes 2 to 20 ethylene glycol moieties, such as 2 to 15, 2 to 10, 3 to 20, 3 to 15, 3 to 10, 4 to 15, 5 to 15 or 5 to 10 ethylene glycol moieties. In some instances, the linking moiety of Formula XVI includes 2 or Attorney Ref: 92VF-350823-WO Client Ref: 021WO more ethylene glycol moieties, such as 3 or more, 4 or more, 5 or more, 6 or more, 7 or more, or even more ethylene glycol moieties. In some embodiments, the linking moiety of Formula XVI includes one or more triazole linking moieties. In some instances, the linker includes one or more 1,2,3-triazole linking moieties. In some embodiments, the one or more 1,2,3-triazoel moieties is selected from one of the following structures: NNNNNN Nw1Nw1 w1NN N O , , wherein w1, u1 and q1 are independently 1 to 25 (e.g., 1 to 12, such as 1 to 6). embodiments, the lin3 king moiety L includes C10-C20-alkylene (e.g., C12-alkylene), or -(OCH2CH2)p-, where p is 1 to 25, such as 3 to 25, 5 to 24, 7 to 25, 10 to 25, 15 to 25 or 20 to 24. In some embodiments, the linker (i.e., L1-L6) comprises Formula XVII: H *OO N O wherein: a is 0 to 12 (e.g., 2 to 6, or 2, or 3); b is 1 to 6 (e.g., 1, 2, or 3); c is 1 to 6 (e.g., 1, 2, or 3); r is 1 or 2; d is 1 to 6 (e.g., 1, 2, or 3); e is b is 1 to 6 (e.g., 1, 2, or 3); f is 1 to 6 (e.g., 1, 2, or 3); and Z is a residual moiety resulting from the covalent linkage of a chemoselective ligation group (e.g., as described herein) of a linker precursor to a compatible group of Y-B. Attorney Ref: 92VF-350823-WO Client Ref: 021WO In some embodiments of the Formula XVII, Z or the terminal L6is a residual moiety resulting from the covalent linkage (e.g., via a thioether bond) of a thiol-reactive chemoselective ligation group to one or more cysteine residue(s) of Y-B. In some embodiments, the thiol-reactive chemoselective ligation group includes maleimide, bromomaleimide, haloacetamide, vinyl sulfone, or thiolactone. In some embodiments, the thiol-reactive group is selected from one of the following structures: O O O X , wherein: u is 1 to 11 (e.g., 1 to 5); v is 1 to 11 (e.g., 1 to 5); and X is H or Br. In some embodiments of formula XVII, Z is a residual moiety resulting from the covalent linkage (e.g., via an amide bond) of an amine-reactive chemoselective ligation group to one or more lysine residue(s) of Y-B. In some embodiments, the amine-reactive chemoselective ligation group includes an active ester (e.g., N-hydroxysuccinimidyl (NHS) ester, sulfo-NHS ester, pentafluorophenyl (PFP) ester, tetrafluorophenyl (TFP) ester, or the like). In some embodiments, the linker (i.e., L1-L6) comprises one of Formula XVIIIa-XVIIIc: H *ON O or Attorney Ref: 92VF-350823-WO Client Ref: 021WO O * H N a N O O a is 0 to 12 (e.g., 2 to 6, or 2, or 3); b is 1 to 6 (e.g., 1, 2, or 3); c is 1 to 6 (e.g., 1, 2, or 3); r is 1 or 2; d is 1 to 6 (e.g., 1, 2, or 3); e is b is 1 to 6 (e.g., 1, 2, or 3); and f is 1 to 6 (e.g., 1, 2, or 3). In some embodiments, the linker (i.e., L1-L6) comprises LA: *O 4O Z OOwherein: Z4is selected from -NHC(O)NH-, -NHC(O)-, -C(O)NH-, -O-, -NH-; a is 0 to 12 (e.g., 2 to 6, or 2, or 3); b is 1 to 6 (e.g., 1, 2, or 3); c is 1 to 6 (e.g., 1, 2, or 3); d is 1 to 6 (e.g., 1, 2, or 3); e is b is 1 to 6 (e.g., 1, 2, or 3); and f is 1 to 6 (e.g., 1, 2, or 3). In some embodiments of LA, Z4is -NHC(O)NH-. In some cases, Z4is -NHC(O)-. In some cases, Z4is -C(O)NH-. In some cases, Z4is -O-. In some cases, Z4is -NH-. Attorney Ref: 92VF-350823-WO Client Ref: 021WO In some embodiments of LA, a is 1-4; b is 1-4; c is 1-3; d is 1-3; e is 1-6; and f is 1-3. In some embodiments, a is 4; b is 1; c is 2; d is 2; e is 5; and f is 2. In some embodiments, Z4is -NHC(O)NH- and a is 1-4; b is 1-4; c is 1-3; r is 1; d is 1-3; e is 1-6; and f is 1-3. In some embodiments, Z4is -NHC(O)- and a is 1-4; b is 1-4; c is 1-3; r is 1; d is 1-3; e is 1- 6; and f is 1-3. In some embodiments, the linker (i.e., L1-L6) comprises LB: H *OON b O O a c a is 0 to 12 (e.g., 2 to 6, or 2, or 3); b is 1 to 6 (e.g., 1, 2, or 3); c is 1 to 6 (e.g., 1, 2, or 3); r is 1 or 2; d is 1 to 6 (e.g., 1, 2, or 3); e is b is 1 to 6 (e.g., 1, 2, or 3); and f is 1 to 6 (e.g., 1, 2, or 3). In some embodiments of LB, a is 1-4; b is 1-4; c is 1-3; r is 1; d is 1-3; e is 1-6; and f is 1-3. In some embodiments, a is 4; b is 1; c is 2; r is 1; d is 2; e is 5; and f is 2. In some embodiments, a is 2; b is 1; c is 2; r is 1; d is 2; e is 3; and f is 2. In some embodiments, a is 4; b is 1; c is 2; r is 1; d is 2; e is 3; and f is 2. In some embodiments, a is 1; b is 2; c is 2; r is 1; d is 2; e is 3; and f is 2. In some embodiments, a is 0; b is 3; c is 2; r is 1; d is 2; e is 3; and f is 2. In some embodiments of LB, a is 1-4; b is 1-4; c is 1-3; r is 2; d is 1-3; e is 1-6; and f is 1-3. In some embodiments, a is 2; b is 1; c is 2; r is 2; d is 2; e is 3; and f is 2. In some embodiments, a is 4; b is 1; c is 2; r is 2; d is 2; e is 3; and f is 2. In some embodiments, a is 1; b is 2; c is 2; r is 2; d is 2; e is 3; and f is 2. In some embodiments, a is 0; b is 3; c is 2; r is 2; d is 2; e is 3; and f is 2. In some embodiments, the linker (i.e., L1-L6) comprises LC: Attorney Ref: 92VF-350823-WO Client Ref: 021WO O * H N a N O O wherein: a is 0 to 12 (e.g., 1 to 6, 2 to 6, or 2, or 3); b is 1 to 6 (e.g., 1 to 4, such as 1, 2, or 3); c is 1 to 6 (e.g., 1 to 3, such as 1, 2, or 3); r is 1 or 2; d is 1 to 6 (e.g., 1 to 3, such as 1, 2, or 3); e is b is 1 to 6 (e.g., 1, 2, or 3); and f is 1 to 6 (e.g., 1 to 3, such as 1, 2, or 3). In some embodiments of Lc, a is 1-4; b is 1-4; c is 1-3; r is 1; d is 1-3; e is 1-6; and f is 1-3. In some embodiments, a is 2; b is 4; c is 2; r is 1; d is 2; e is 5; and f is 2. In some embodiments of Lc, a is 1-4; b is 1-4; c is 1-3; r is 2; d is 1-3; e is 1-6; and f is 1-3. In some embodiments, a is 2; b is 4; c is 2; r is 2; d is 2; e is 5; and f is 2. In some embodiments, the -Z1-L1- includes a group selected from: R21O21N R N ; wherein R24and R25are substituted C(1-6)alkyl, optionally substituted fluoroalkyl, and halogen; and each R21is independently selected from H, optionally substituted (C1-C6)alkyl, and optionally substituted alkanoyl. In some embodiments, R21is H. In some embodiments, R24is C(1-3)-alkyl, or C(1-3)-fluoroalkyl. In some cases, the fluoroalkyl is CF3. In some embodiments, R25is C(1-3)-alkyl, or C(1-3)-fluoroalkyl. In some cases, the fluoroalkyl is CF3. In some embodiments, the linker includes a polypeptide scaffold where some or all of the sidechain groups of the amino acid residues of such a polypeptide scaffold have been modified to attach a X binding moiety (e.g., as described herein). It is understood that X binding moieties (e.g., as described Attorney Ref: 92VF-350823-WO Client Ref: 021WO herein) can be conjugated to amino acid residues, such as Asp, Lys, Orn, Glu, and Ser, of a polypeptide containing linker via a convenient conjugation chemistry. In some embodiments, the linker contains a polylysine polypeptide. In some embodiments, the linker contains a polyornithine polypeptide. In some embodiments, the linker contains a polyserine polypeptide. In some embodiments, the linker contains a polyaspartate polypeptide. The polypeptide backbone of such a linker can be a randomly polymerized polymer having an average length, or a polymer of defined length prepared e.g., in a controlled stepwise fashion. In some cases, the polypeptide linker has a length of 10-100 amino acid residues, such as 20-90, or 20-50 amino acid residues. In some embodiments, the N-terminal or C-terminal of the polypeptide linker is modified to include a linking moiety to an additional X binding moiety (e.g., as described herein). In some embodiments, the N-terminal or C-terminal of the polypeptide linker segment is modified with one or more linking moieties (e.g., as described herein) suitable for attachment to a protein construct (Y-B) including a polypeptide that specifically binds target autoantibody. In some embodiments of the linker of formula (II), L1to L3each independently comprise one or more linking moieties independently selected from -C1-20-alkylene-, -NHCO-C1-6-alkylene-, -CONH-C1-6- alkylene-, -NH C1-6-alkylene-, -NHCONH-C1-6-alkylene-, - NHCSNH-C1-6-alkylene-, -C1-6-alkylene- NHCO-, -C1-6-alkylene-CONH-, -C1-6-alkylene-NH-, -C1-6-alkylene-NHCONH-, -C1-6-alkylene- NHCSNH-, -O(CH2)p-, -(OCH2CH2)p-, -NHCO-, -CONH-, -NHSO2-, -SO2NH-, -CO-, -SO2-, -O-, -S-, monocyclic heteroaryl (e.g., 1,2,3-triazole), monocyclic aryl (e.g., phenyl, e.g., 1,4-linked phenyl or 1,3- linked phenyl), monocyclic heterocycle (e.g., pyrrolidine-2,5-dione, piperazine or piperidine ring as described herein), amino acid residue (naturally or non- naturally occurring amino acid residue), -NH-, and -NCH3-, wherein each p is independently1 to 50. In some embodiments of the linker of formula (II), any of L1-L3comprises repeating ethylene glycol moieties (e.g., -CH2CH2O- or -OCH2CH2-). In some embodiments, the linker of formula (II) comprises 1 to 25 ethylene glycol moieties, such as 3 to 25, 5 to 25, 7 to 25, 10 to 25, 15 to 25, 17 to 25, 20 to 25, or 22 to 25 ethylene glycol moieties. In some instances, the linker of formulae (II) comprises 3 or more ethylene glycol moieties, such as 5 or more, 7 or more, 10 or more, 15 or more, 20 or more, or even more ethylene glycol moieties. In some embodiments of the linker of formula (II), any of L1-L3comprises one or more triazole linking moieties. In some instances, the linker comprises one or more 1,2,3-triazole linking moieties. In some embodiments, the one or more 1,2,3-triazole moieties is selected from one of the following structures: Attorney Ref: 92VF-350823-WO Client Ref: 021WO NNNw1NNNNw1N NNw1N O , , wherein w1, u1 and q1 are independently 1 to 25 (e.g., 1 to 12, such as 1 to 6). embodiments of the linker of formula (II), n is 1, such that b is 0, and the linker is of the formula (IIa): ** (L1)a (L3)c ***IIa wherein L1and L3are independently a linker (e.g., as described herein), wherein L1to L3together provide a linear linker between X and Y; a is 1; c is 0 or 1; ** represents the point of attachment to L1of X via Z1; and *** represents the point of attachment to Y. In some embodiments, the linear linker has a backbone of 20 or more consecutive atoms covalently linking X to Y via Z1, such as a backbone of 25 or more consecutive atoms, or 30 or more consecutive atoms, and in some cases, up to 100 consecutive atoms. In some embodiments of formula (IIa), the linear linker separates X and Y (or Z1) by a chain of 20 to 50 consecutive atoms. In someembodiments, the linear linker separates X and Y (or Z1) by a chain of 21 to 50 consecutive atoms, by a chain of 22 to 50 consecutive atoms, by a chain of 23 to 50 consecutive atoms, by a chain of 24 to 50 consecutive atoms, by a chain of 25 to 50 consecutive atoms, by a chain of 26 to 50 consecutive atoms, by a chain of 27 to 50 consecutive atoms, by a chain of 28 to 50 consecutive atoms, or by a chain of 29 to 50 consecutive atoms. In some embodiments of formula (IIa), the linear linker separates X and Y (or Z1) by a chain of 30 to 60 consecutive atoms. In some embodiments, the linear linker separates X and Y (or Z1) by a chain of 31 to 60 consecutive atoms. In some embodiments, the linear linker separates X and Y (or Z1) by a chain of 32 to 60 consecutive atoms. In some embodiments, the linear linker separates X and Y (or Z1) by a chain of 33 to 60 consecutive atoms. In some embodiments, the linear linker separates X and Y (or Z1) by a chain of 34 to 60 consecutive atoms. In some embodiments, the linker (i.e., L1-L6) Attorney Ref: 92VF-350823-WO Client Ref: 021WO comprises separates X and Y (or Z1) by a chain of 35 to 50 consecutive atoms. In some embodiments, the linker (i.e., L1-L6) comprises separates X and Y (or Z1) by a chain of 36 to 50 consecutive atoms. In some embodiments, the linker (i.e., L1-L6) comprises separates X and Y (or Z1) by a chain of 41 to 50 consecutive atoms. In some embodiments, the linker (i.e., L1-L6) comprises separates X and Y (or Z1) by a chain of 46 to 50 consecutive atoms. In some embodiments, n is 2 or more, such that L1to L3together provide a branched linker between X and Y. In some embodiments, n is 2 or more, and L2is selected from: O In some embodiments, L1-L2comprises a backbone of 14 or more consecutive atoms between X and the branching atom, such as 14 to 50, 14 to 40, 14 to 35 or 14 to 30 consecutive atoms between X and the branching atom. In some embodiments, L3comprises a backbone of 10 to 80 consecutive atoms, such as 12 to 70, 12 to 60, or 12 to 50 consecutive atoms. In some embodiments, wherein L3comprises a linking moiety selected from (C10-C20-alkylene (e.g., C12-alkylene), or -(OCH2CH2)p-, where p is 1 to 25, such as 3 to 25, 5 to 24, 7 to 25, 10 to 25, 15 to 25 or 20 to 24. In some embodiments, L1to L5each independently comprise one or more linking moieties independently selected from -C1-20-alkylene-, -NHCO-C1-6-alkylene-, -CONH-C1-6-alkylene-, -NH C1-6-alkylene-, -NHCONH-C1-6-alkylene-, - NHCSNH-C1-6-alkylene-, -C1-6-alkylene-NHCO-, -C1-6-alkylene-CONH-, -C1-6-alkylene-NH-, -C1-6-alkylene-NHCONH-, -C1-6-alkylene-NHCSNH-, Attorney Ref: 92VF-350823-WO Client Ref: 021WO -O(CH2)p-, -(OCH2CH2)p-, -NHCO-, -CONH-, -NHSO2-, -SO2NH-, -CO-, -SO2-, -O-, -S-, monocyclic heteroaryl (e.g., 1,2,3-triazole), monocyclic aryl (e.g., phenyl, e.g., 1,4-linked phenyl or 1,3-linked phenyl), monocyclic heterocycle (e.g., pyrrolidine-2,5-dione, piperazine or piperidine ring as described herein), amino acid residue (naturally or non- naturally occurring amino acid residue), -NH-, and -NCH3-, wherein each p is independently1 to 50. In some embodiments, -(L1)a- comprises an optionally substituted alkyl or ethylene glycol linking moiety. In some embodiments, L1comprises an optionally substituted -C1-6-alkylene-. In some embodiments, L1comprises an ethylene glycol linking moiety. In some embodiments, each L1is independently selected from -C1-6-alkylene-, -(CH2CH2O)t-, -C1-6-alkylene-NR4CO-, -C1-6-alkyleneCONH-, or OCH2, wherein t is 1 to 20; and each R4is independently selected from H, and optionally substituted (C1-C6)alkyl. In some embodiments, each L1is -C1-6-alkylene-, such as -C1-3-alkylene-. In some embodiments, each L1is -(CH2CH2O)t-, where t is 1 to 20, such as 1 to 15, 1 to 10, 1 to 8, 1 to 6, or 1 to 4. In some embodiments, each L1is --C1-6-alkylene- NR4CO-. In some embodiments, each L1is -C1-6-alkyleneCONH-. In some embodiments, each L1is or OCH2. In some embodiments, one or more L1is independently -CH2O-, -(CH2CH2O)t-, -NR4CO-, substituted (C1-C6)alkoxy, COOH, NO2, CN, NH2, -N(R21)2, -OCOR21, -COOR21, -CONHR21, and -NHCOR21; and each r independently 0 to 20, and any of the L1moieties are optionally further substituted. In some embodiments, L2is -OCH2-. In certain other embodiments, L2is (OCH2CH2)q-, and q is 1 to 10, 1 to 9, 1 to 8, 1 to 7, 1 to 6, 1 to 5, 1 to 4, 1 to 3 or 1 to 2. In some embodiments, q is 2 to 8, such as 2 to 6 , 4 to 6, or 2 to 4. Attorney Ref: 92VF-350823-WO Client Ref: 021WO In some embodiments, L3is absent or independently selected from -C1-6-alkylene-, -(CH2CH2O)t-, --C1-6-alkylene-NHCO-, -C1-6-alkyleneCONH-,or OCH2, wherein t is 1 to 20. In some embodiments, L3is absent. In some embodiments, L3is -C1-6-alkylene-. In some embodiments, L3is -(CH2CH2O)t-, where t is 1 to 20, such as 1 to 15, 1 to 12, 1 to 10, 1 to 8, 1 to 6, 1 to 4 or 1 to 3. In some embodiments, L3is -C1-6-alkylene-NHCO-. In some embodiments, L3is -C1-6-alkyleneCONH-. In some embodiments, L3is OCH2. In some embodiments of formula (IIb), one or more L4is a branched linking moiety. In some embodiments of formula (IIb), one or more L4is a branched linking moiety selected from: O , embodiments, each x is 1, 2 or 3, e.g., 2. In some embodiments, L5comprises one or more of: an amino acid residue (e.g., Asp, Lys, Orn, Glu), an amino acid analogue, N-substituted amido (-N(-)C(=O)-), tertiary amino, polyol (e.g., O- substituted glycerol), and the like. Analogs of an amino acid, include but not limited to, unnatural amino acids, as well as other modifications known in the art. The amino acid includes L-amino acids, D-amino acids, or both, and may contain any of a variety of amino acid modifications or analogs known in the art. In some embodiments, the linker includes a polypeptide scaffold where some or all of the sidechain groups of the amino acid residues have been modified to attach a X binding moiety (e.g., as described herein). It is understood that X binding moieties (e.g., as described herein) can be conjugated to amino acid residues, such as Asp, Lys, Orn, Glu, and Ser, of a polypeptide containing linker via a convenient conjugation chemistry. In some embodiments, the linker contains a polylysine polypeptide. In some embodiments, the linker contains a polyornithine polypeptide. In some embodiments, the linker contains a polyserine polypeptide. In some embodiments, the linker contains a polyaspartate polypeptide. Attorney Ref: 92VF-350823-WO Client Ref: 021WO The polypeptide can be a randomly polymerized polymer having an average length, or a polymer of defined length prepared e.g., in a controlled stepwise fashion. In some cases, the polypeptide linker segment has a length of 10-100 amino acid residues, such as 20-90, or 20-50 amino acid residues. In some embodiments, the N-terminal or C-terminal of the polypeptide linker segment is modified to include a linking unit to an additional M6PR binding moiety (e.g., as described herein). In some embodiments, the N-terminal or C-terminal of the polypeptide linker segment is modified with one or more linking units (e.g., as described herein) suitable for attachment to a Y moiety of interest. In some embodiments, a is 1. In some embodiments, at least one of b, c, d, and e is not 0. In some embodiments, b is 1 or 2. In some embodiments, c is 1 or 2. In some embodiments, e is 1 or 2. In some embodiments, b, d and e are independently 1 or 2. In some embodiments, a, b, d, and e are each 1, and c is 0. In some embodiments, the linker comprises 20 to 100 consecutive atoms, such as 20 to 90, 20 to 80, 20 to 70, 20 to 60, 20 to 50, 20 to 40 or 20 to 30 consecutive atoms. In some embodiments, the linker comprises 25 to 100 consecutive atoms, such as 30 to 100, 35 to 100, 40 to 100, 45 to 100, 50 to 100, 55 to 100, 60 to 100, 65 to 100, 70 to 100, 75 to 100, 80 to 100, 85 to 100, 90 to 100, or 95 to 100 consecutive atoms. In some embodiments, the linker comprises 25 or more consecutive atoms, such as 26 or more, 27 or more, 28 or more, 29 or more or 30 or more consecutive atoms. In some embodiments, the linker comprises 30 or more consecutive atoms, such as 31 or more, 32 or more, 33 or more, 34 or more, 35 or more, 36 or more, 37, or more, 38 or more, 39 or more, 40 or even more consecutive atoms. In some embodiments, the linker is a branched linker or linking moiety as shown in Table 1. Table 1. Exemplary branched linkers and branched linking moieties Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 1. Exemplary branched linkers and branched linking moieties Linker No Linker structure

[0002] Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 1. Exemplary branched linkers and branched linking moieties Linker No Linker structure Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 1. Exemplary branched linkers and branched linking moieties Linker No Linker structure Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 1. Exemplary branched linkers and branched linking moieties Linker No Linker structure Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 1. Exemplary branched linkers and branched linking moieties Linker No Linker structure A chemoselective ligation group is a group having a reactive functionality or function group capable of conjugation to a compatible group of a second moiety. For example, chemoselective ligation groups (or a precursor thereof) may be one of a pair of groups associated with a conjugation chemistry such as azido-alkyne click chemistry, copper free click chemistry, Staudinger ligation, tetrazine ligation, hydrazine-iso-Pictet-Spengler (HIPS) ligation, cysteine-reactive ligation chemistry (e.g., thiol-maleimide, thiol-haloacetamide or alkyne hydrothiolation), amine-active ester coupling, tyrosine specific conjugation chemistry (e.g., e-Y-CLICK), methionine specific conjugation chemistry (e.g., oxaziridine-based or ReACT chemistry), reductive amination, dialkyl squarate chemistry, etc. Chemoselective ligation groups that may be utilized in linking two moieties, include, but are not limited to, amino (e.g., a N-terminal amino or a lysine sidechain group of a polypeptide), azido, aryl Attorney Ref: 92VF-350823-WO Client Ref: 021WO azide, alkynyl (e.g., ethynyl or cyclooctyne or derivative), active ester (e.g., N-hydroxysuccinimide (NHS) ester, sulfo-NHS ester or PFP ester or thioester), haloacetamide (e.g., iodoacetamide or bromoacetamide), chloroacetyl, bromoacetyl, hydrazide, maleimide, vinyl sulfone, 2-sulfonyl pyridine, cyano-alkyne, thiol (e.g., a cysteine residue), disulfide or protected thiol, isocyanate, isothiocyanate, aldehyde, ketone, alkoxyamine, hydrazide, aminooxy, phosphine, HIPS hydrazinyl-indolyl group, or aza- HIPS hydrazinyl-pyrrolo-pyridinyl group, tetrazine, cyclooctene, squarate, and the like. In some instances, chemoselective ligation group is capable of spontaneous conjugation to a compatible chemical group when the two groups come into contact under suitable conditions (e.g., copper free Click chemistry conditions). In some instances, the chemoselective ligation group is capable of conjugation to a compatible chemical group when the two groups come into contact in the presence of a catalyst or other reagent (e.g., copper catalyzed Click chemistry conditions). In some embodiments, the chemoselective ligation group is a photoactive ligation group. For example, upon irradiation with ultraviolet light, a diazirine group can form reactive carbenes, which can insert into C-H, N-H, and O-H bonds of a second moiety. In some instances, the terminal L moiety (e.g., the terminal L6) is a precursor of the reactive functionality or function group capable of conjugation to a compatible group of a second moiety. For example, a carboxylic acid is a precursor of an active ester chemoselective ligation group. In some embodiments, the terminal L moiety (e.g., the terminal L6) is a reactive moiety capable forming a covalent bond to a polypeptide (e.g., with an amino acid sidechain of a polypeptide having a compatible reactive group). The reactive moiety can be referred to as a chemoselective ligation group. In some embodiments, the terminal L moiety (e.g., the terminal L6) is a thio-reactive chemoselective ligation group (e.g., as described in Table 2). In some cases, Y can produce a residual moiety Z resulting from the covalent linkage of a thiol-reactive chemoselective ligation group to one or more cysteine residue(s) of a protein, e.g., B or Y. In some embodiments, the terminal L moiety (e.g., the terminal L6) is a Cys-reactive chemoselective ligation group (e.g., a maleimide derivative as described herein). In some cases, the Cys- reactive chemoselective ligation group includes a maleimide group. In some embodiments, the chemoselective ligation group includes a maleimide group, e.g., mal-1 to mal-7. In some embodiments, the terminal L moiety (e.g., the terminal L6) is an amino-reactive chemoselective ligation group. In some cases, the terminal L moiety (e.g., the terminal L6) can produce a residual moiety Z resulting from the covalent linkage of an amine-reactive chemoselective ligation group to one or more lysine residue(s) a protein, e.g., B or Y. Attorney Ref: 92VF-350823-WO Client Ref: 021WO In some embodiments, the terminal L moiety (e.g., the terminal L6) is a Lys-reactive chemoselective ligation group. In some embodiments the Lys-reactive chemoselective ligation group is a PFP ester. Exemplary chemoselective ligation groups, and synthetic precursors thereof, which may be adapted for use in the compounds of this disclosure are shown in Table 2. In Table 2, the can represent a point of attachment a linking moiety (or a linked X moiety). Table 2: Exemplary chemoselective ligation groups and precursors d Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 2: Exemplary chemoselective ligation groups and precursors Groups Exemplary structures Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 2: Exemplary chemoselective ligation groups and precursors Groups Exemplary structures Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 2: Exemplary chemoselective ligation groups and precursors Groups Exemplary structures l, Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 2: Exemplary chemoselective ligation groups and precursors Groups Exemplary structures Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 2: Exemplary chemoselective ligation groups and precursors Groups Exemplary structures Table 3 shows exemplary residual moieties, wherein the “***” indicates the point of attachment of Y. Table 3: Exemplary residual moieties from chemoselective ligation groups and precursors . Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 3: Exemplary residual moieties from chemoselective ligation groups and precursors Groups Exemplary residual moieties This disclosure includes compounds which can be prepared from a precursor ligand-linker compound including a chemoselective ligation group as described herein. The chemoselective ligation group of such compounds can be utilized to connect to a Y-B complex. It is understood that any of these compounds can also be prepared de novo to include an alternative Y moiety of interest (e.g., as described below) rather than the chemoselective ligation group. In some embodiments, such compounds are referred to as a conjugate, e.g., a biomolecule conjugate that specifically binds a target protein. The examples described herein show specific, non-limiting, ASGPR binding compounds having chemoselective ligation group. For example, in some embodiments, provided is a conjugate (i.e., LYTAC) of Formula:

[0003] Attorney Ref: 92VF-350823-WO Client Ref: 021WO HO OO OHO NH , B ,

[0004] Attorney Ref: 92VF-350823-WO Client Ref: 021WO OOO HN O O or m is 1 to 10; Y is a carrier polypeptide connected to B; and B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody. In some embodiments, provided is a conjugate (i.e., LYTAC) of Formula: Attorney Ref: 92VF-350823-WO Client Ref: 021WO HO OO OHO NH , B ,

[0005] Attorney Ref: 92VF-350823-WO Client Ref: 021WO OOHN O O O or m is 4 to 6; Y is a carrier polypeptide connected to B; and B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody. Exemplary carrier polypeptides and thyroid-stimulating hormone receptor (TSHR) polypeptides are described herein. Attorney Ref: 92VF-350823-WO Client Ref: 021WO 1.1.4 TSHR Polypeptides As summarized above, the bifunctional compounds of this disclosure can include a thyroid stimulating hormone receptor (TSHR) polypeptide that specifically binds a target anti-TSHR autoantibody. Thyroid stimulating hormone receptor is a postsynaptic integral membrane protein that plays a pivotal role in the development of the neuromuscular junction synapse (NMJ). Anti-TSHR autoantibodies are associated with Graves’ disease. In some embodiments, the anti-TSHR autoantibody is an IgG antibody, e.g., an IgG2 antibody. TSHR is an 87 kDa transmembrane receptor composed of a large amino-terminal extracellular domain (ECD) and a transmembrane domain (TMD). The TSHR ECD contains an N-terminal domain, a leucine-rich repeat domain (LRD) and a hinge region or cleavage domain. The TMD contains the typical seven transmembrane helices of GPCRs, an eighth helix parallel to the membrane and a C-terminal tail. The extracellular domains (ECD) of the TSHR molecule contain the sites of binding (e.g., epitopes) of the disease-causing anti-TSHR autoantibodies (e.g., M22). In particular, the leucine-rich repeat domain (LRD) of TSHR can be considered antigens that contain the primary immunogenic or epitope-containing regions of the TSHR protein where anti-TSHR autoantibodies predominantly bind. In some embodiments, the TSHR polypeptide is an antigen that includes one or more epitope- containing domains, or antibody binding fragments thereof, of the full length TSHR protein. In some embodiments, the TSHR polypeptide includes an extracellular domain of TSHR, or an antigenic (e.g., epitope-containing) fragment thereof. In some embodiments, the TSHR polypeptide includes leucine-rich repeat domain (LRD) of TSHR, or an antigenic fragment thereof. In some embodiments, the TSHR polypeptide includes 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 amino acid addition, deletion, or substitution compared to a sequence of a human TSHR protein (SEQ ID NO: 1), or an antigenic fragment thereof. In some embodiments, the TSHR polypeptide has at least 80%, at least 85%, at least 90%, at least 91 %, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or at least 100% sequence identity to the human TSHR protein (SEQ ID NO: 1) or an antigenic portion (e.g., antigenic domain or fragment thereof) of the human TSHR protein (SEQ ID NO: 1). In SEQ ID NO: 1 below (Table 4), the leucine-rich repeat domain (LRD) is bold and underlined, and the rest of extracellular domain is underlined. In some embodiments the TSHR polypeptide is derived from the extracellular domain of TSHR, which is shown in Table 4 below. In some embodiments, the TSHR polypeptide includes 1, 2, 3, 4, 5, 6, Attorney Ref: 92VF-350823-WO Client Ref: 021WO 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 amino acid addition, deletion, or substitution compared to a sequence of Table 4, or an antigenic fragment thereof. In some embodiment, the TSHR polypeptide includes a sequence having at least 80%, at least 85%, at least 90%, at least 91 %, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or at least 100% sequence identity to a sequence of Table 4, or an antigenic fragment thereof. In some embodiments, the TSHR polypeptide includes a polypeptide of Table 4. In some embodiments, the TSHR polypeptide consists essentially of a polypeptide of one of Table 4. Table 4: Exemplary TSHR polypeptide sequences TSHR Sequence SEQ ID NO: Attorney Ref: 92VF-350823-WO Client Ref: 021WO TSHR Sequence SEQ ID polypeptide NO: n some em o mens, e po ypep e nc u es one or more am no ac su s u ons selected from H63C, R112P, D143P, D151E, V169R, C176S, K250Q, and I253R as compared to a wild type TSHR (SEQ ID NO: 1). In some embodiments, the TSHR polypeptide includes one or more amino acid substitutions selected from R112P, D143P, D151E, V169R, C176S, K250Q, and I253R as compared to a sequence of SEQ ID NO: 1. In some embodiments, the TSHR polypeptide includes one or more amino acid substitutions selected from H63C, R112P, D143P, D151E, V169R, I253R as compared to a sequence of SEQ ID NO: 1. For example, the TSHR polypeptide includes a sequence having at least 80% ,at least 85%, at least 90%, at least 91 %, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or at least 100% sequence identity to a sequence of Table 5, or an antigenic fragment thereof. In some embodiments, the TSHR polypeptide includes a polypeptide of Table 5. In some embodiments, the TSHR polypeptide consists essentially of a polypeptide of one of Table 5. In some embodiments, the TSHR polypeptide, B of Formula I, comprises any one of SEQ ID NOs: 1-7. In some embodiments, the TSHR polypeptide, B of Formula I, comprises SEQ ID NO: 6. In some embodiments, Y-B comprises any one of SEQ ID NOs: 1-7. In some embodiments, the TSHR polypeptide, B of Formula I, includes 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20 amino acid addition, deletion, or substitution compared to any one of SEQ ID NOs: 1-7, or an antigenic fragment thereof. In some embodiment, the TSHR polypeptide, B of Formula I, includes a sequence having at least 80%, at least 85%, at least 90%, at least 91 %, at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, at least 97%, at least 98%, at least 99%, or at least 100% sequence identity to any one of SEQ ID NOs: 1-7, or an antigenic fragment thereof. In some embodiments, the TSHR polypeptide, B of Formula I, includes a polypeptide of any one of SEQ ID NOs: 1-7. In some embodiments, the TSHR polypeptide, B of Formula I, consists essentially of a polypeptide any one of SEQ ID NOs: 1-7. Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 5: Exemplary TSHR polypeptide sequences TSHR Sequence SEQ ID ol e tide NO: 1.1.5 Carrier Polypeptide A number of strategies, such as attachment of a carrier, for imparting desirable pharmacokinetic properties to a peptide or protein (e.g., avoidance of rapid renal clearance, and / or optimizing Fc receptor mediated recycling) can be adapted for use in the bifunctional molecules of this disclosure that contain a target binding the TSHR polypeptide. The TSHR polypeptide can be connected to a carrier polypeptide Y that imparts one or more desirable properties onto the resulting bifunctional molecule (e.g., increase in vivo stability and / or half- Attorney Ref: 92VF-350823-WO Client Ref: 021WO life), and / or provides for conjugation sites to a ligand-linker moiety, e.g., without disrupting the autoantibody binding properties of the TSHR polypeptide. In some embodiments, the TSHR polypeptide is synthetically linked to a carrier polypeptide Y. In some embodiments of formula (I), the carrier polypeptide Y is conjugated to a TSHR polypeptide (B) via a bifunctional linker. In some embodiments, the TSHR polypeptide is linked to a carrier polypeptide Y as part of a protein construct, such as a chimeric fusion protein. In some embodiments, the TSHR polypeptide B and the carrier polypeptide Y are fused directly to each other, e.g., via N-terminal to C-terminal fusion, or C- terminal to N-terminal fusion. In some embodiments, the TSHR polypeptide B and the carrier polypeptide Y are fused indirectly via a spacer domain. In some embodiments, the Y-B of formula (I) is a chimeric protein having a polypeptide encoded by a nucleic acid molecule that encodes for both a TSHR polypeptide B and the carrier polypeptide Y. The carrier polypeptide (Y) can be a serum protein or domain of a serum protein. In some embodiments, the serum protein is an albumin. In some embodiments, the serum protein is an immunoglobulin. In some embodiments, the carrier polypeptide (Y) is an engineered serum protein or domain thereof. The carrier polypeptide (Y) can be prepared synthetically, or recombinantly. 1.1.5.1 Albumin The carrier polypeptide can be a serum albumin protein or domain or subdomain thereof, or fragment thereof. In some embodiments, the carrier polypeptide is human serum albumin (HSA). Albumins generally have a long plasma half-life (e.g., about 3 weeks) and can provide a scaffold to which bioactive molecules can be attached or fused. HSA has a long serum half-life in humans that is attributed in part to its interaction with neonatal Fc receptor (FcRn). HSA (molecular mass 66.5 kDa) includes three structurally similar and flexible domains: I (residues 1-195), II (196-383) and III (384-585). Each domain (D) is composed of two subdomains A and B (e.g., DIA [5-105], DIB [119-195], DIIA [196-292], DIIB [314-383], DIIIA [384-491], DIIIB [510-582], e.g., as referenced to SEQ ID NO: 2 of WO2017 / 029407) with common structural motifs. In some embodiments, the carrier protein is an HSA variant having enhanced FcRn binding. FcRn binds to the C-terminal end of DIII of HSA and protects albumin from intracellular degradation. For instance, a single amino acid substitution within HSA DIII (K537P) shows 12-fold improved binding affinity to FcRn, which translates into longer half-life. Various amino acid residues of albumin located in Domain I or Domain II also affect HSA interaction with FcRn (e.g., WO 2013 / 135896 describes albumin Attorney Ref: 92VF-350823-WO Client Ref: 021WO variants having one or more alterations in Domain I and one or more alterations in Domain III; WO 2015 / 036579 describes albumin variants having one or more alterations in Domain II). Any convenient albumin protein can be a parent for an albumin variant that can be utilized as a carrier polypeptide. As an example, human serum albumin (HSA) such as AAA98797, P02768-1, SEQ ID NO.15 (mature HSA), or SEQ ID NO.14 (precursor HSA). In some embodiments, other albumins are utilized as a carrier polypeptide. Such other albumins include, but are not limited to, primate serum albumin (e.g.,, chimpanzee serum albumin, XP_517233.2), gorilla serum albumin or macaque serum albumin (e.g., NP_001182578), rodent serum albumin (e.g.,, hamster serum albumin, A6YF56), guinea pig serum albumin (e.g., Q6WDN9-1), mouse serum albumin (e.g., AAH49971, P07724-1 Version 3) and rat serum albumin (e.g., AAH85359, P02770-1 Version 2), bovine serum albumin (e.g., cow serum albumin P02769-1), equine serum albumin such as horse serum albumin (e.g., P35747-1), or donkey serum albumin (e.g., Q5XLE4-1), rabbit serum albumin (e.g., P49065-1 Version 2), goat serum albumin (e.g., ACF10391), sheep serum albumin (e.g., P14639-1), dog serum albumin (e.g., P49822-1), chicken serum albumin (e.g., P19121 -1 Version 2) and pig serum albumin (e.g., P08835- 1 Version 2) or a polypeptide having at least 70%, 75%, 80%, 85%, 90%, 95%, 96%, 97%, 98%, 99%, 99.2%, 99.4%, 99.6%, or at least 99.8% amino acid sequence identity to such an albumin. Non-mammalian albumins of interest include ovalbumin (e.g., P01012.pro: chicken ovalbumin; 073860. Pro: turkey ovalbumin). In some embodiments, albumin, a fragment thereof, or conjugation-competent albumin variant, or albumin part of a fusion polypeptide or conjugate comprising albumin or a fragment thereof has a polypeptide sequence having at least 80%, 85%, 90%, 91 %, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to SEQ ID NO: 14 (e.g., P02768-1) below, where Domain I is in bold, Domain II is underlined, and Domain III is in italic (Table 6). In some embodiments, albumin, a fragment thereof, or conjugation-competent albumin variant, or albumin part of a fusion polypeptide or conjugate comprising albumin or a fragment thereof has a polypeptide sequence having at least 80%, 85%, 90%, 91 %, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to SEQ ID NO: 15. In some embodiments, the albumin, a fragment thereof, or conjugation-competent albumin variant, or variant thereof of the bifunctional molecule has a sequence identity to the sequence of HSA shown in SEQ ID NO: 15 of at least 80%, 85%, 90%, 91 %, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100%. In some embodiments, the albumin maintains at least one of the major properties of albumin or a similar tertiary structure as an albumin, such as HSA. A functional fragment of albumin may Attorney Ref: 92VF-350823-WO Client Ref: 021WO have a sequence identity of at least 60%, 70%, 80%, 85%, 90%, 91 %, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, 99.2%, 99.4%, 99.6%, 99.8%, or 100% to the sequence of HSA Domain III as shown in SEQ ID NO: 8, or to the sequence of HSA Domain II and Domain III as shown in SEQ ID NO: 9, or to a molecule consisting of or comprising two copies of Domain III (e.g., SEQ ID NO: 10), or to a molecule consisting of or comprising three copies of Domain III (e.g., SEQ ID NO: 11), or to a molecule consisting of or comprising Domain I and two copies of Domain III (e.g., SEQ ID NO: 12). In some embodiments, the carrier polypeptide, or Y of Formula I, comprises any one of SEQ ID NOs: 8, 9, 10, 11, 12, 14, and 15. In some embodiments, Y comprises SEQ ID NO: 15. Table 6 SEQ ID Name Sequence NO:

[0006] Attorney Ref: 92VF-350823-WO Client Ref: 021WO SEQ ID Name Sequence NO: Attorney Ref: 92VF-350823-WO Client Ref: 021WO SEQ ID Name Sequence NO:

[0007] Attorney Ref: 92VF-350823-WO Client Ref: 021WO SEQ ID Name Sequence NO: n. The albumin, a fragment thereof, or conjugation-competent albumin variant, or albumin part of a fusion polypeptide or conjugate comprising albumin or a fragment thereof according to the disclosure, when folded, may have several, for example at least 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 and suitably all 17, of the native disulfide bonds of the polypeptide of SEQ ID NO.15. Albumin carrier polypeptides which can be adapted for use in the bifunctional molecules of this disclosure are described in WO 2017 / 029407, WO 2013 / 135896, WO 2015 / 036579, the disclosures of which are herein incorporated by reference in their entireties. Conjugation of molecules to the free thiol on cysteine-34 of HSA can provide site-selective conjugation. To increase loading potential, recombinant HSA (rHSA) variants can be engineered to contain additional free, conjugation-competent cysteines. The term “thio-albumin” is used to describe an albumin variant which comprises one or more (e.g. several) unpaired cysteine residues, particularly an albumin variant in which one or more (e.g. several) of the unpaired cysteine residues does not occur in a naturally occurring variant of an albumin. A thio-albumin refers to a conjugation-competent albumin. The rHSA variant can be a thio-albumin or a conjugation-competent albumin. The rHSA may have one or more free, conjugation-competent cysteines introduced in Domain I (DI), Domain II (DII), and / or Domain III (DIII). In some embodiments, the rHSA Attorney Ref: 92VF-350823-WO Client Ref: 021WO variant has at least one free, conjugation-competent cysteines introduced in DI or DII. In some embodiments, the rHSA variant has at least one free, conjugation-competent cysteine introduced in DI and DIII. In some embodiments, the rHSA variant has a conjugation site at Cys34 and at least one or more free, conjugation-competent cysteines introduced in DI, DII, and / or DIII. In some embodiments, the carrier polypeptide is an HSA variant engineered for increased stability, conjugation efficiency (Cys or Lys), and / or FcRn binding. In some embodiments, the carrier polypeptide is a rHSA variant having a conjugation position at Cys34 (e.g., in reference to SEQ ID NO: 2) and one or more conjugation-competent cysteines introduced at positions selected from K93, A226, E230, I271, E294, E358, L24, F49, V54, D56, A92, Q94, E97, H128, F156, E227, D237, K240, D259, K262, N267, Q268, L275, L284, K317, A322, E333, D340, E354, K359, A362, E382, and L398 of SEQ ID NO: 15. The free, conjugation-competent cysteines may be introduced by substitution of an amino acid other than cysteine at any one of positions corresponding to or equivalent to any of residues selected from K93, A226, E230, I271, E294, E358, L24, F49, V54, D56, A92, Q94, E97, H128, F156, E227, D237, K240, D259, K262, N267, Q268, L275, L284, K317, A322, E333, D340, E354, K359, A362, E382, and L398 of SEQ ID NO.15, or by insertion of a cysteine at a position adjacent to N- or C- side of an amino acid corresponding to a position equivalent to any of residues selected from K93, A226, E230, I271, E294, E358, L24, F49, V54, D56, A92, Q94, E97, H128, F156, E227, D237, K240, D259, K262, N267, Q268, L275, L284, K317, A322, E333, D340, E354, K359, A362, E382, and L398 of SEQ ID NO: 15. In some embodiments, at least one or more free, conjugation-competent cysteines is introduced at one or more positions corresponding to or equivalent to any of residues selected from C34, V54, H128, K240, and K262. In some embodiments, the carrier polypeptide is a rHSA variant that exhibits up to 95% monomeric stability and retains hFcRn engagement compared with a wildtype unconjugated control (e.g., as demonstrated by Biolayer Interferometry). In some embodiments, introduction of the free, conjugation- competent cysteines into the rHSA variant does not interfere with FcRn binding. In some embodiments, introduction of the free, conjugation-competent cysteines maintains the albumin half-life in circulating blood. 1.1.5.2 Immunoglobulin In some embodiments, the carrier polypeptide is an Fc fragment, a monomer, a dimer, a domain, or fragments thereof. Fc fragments contain the CH2 and CH3 domains and part of the hinge region held together by one or more disulfides and noncovalent interactions. Fc and Fc5µ fragments are produced from fragmentation of IgG and IgM, respectively. Fc fragments are derived from the heavy chain constant Attorney Ref: 92VF-350823-WO Client Ref: 021WO region of an immunoglobulin. In some embodiments, Fc fragments are derived from IgG immunoglobulins of any subclass (e.g., IgG1, IgG2, IgG3, IgG4). In some embodiments, Fc fragments are derived from human IgG1. The term “Fc dimer” refers to an Fc fragment containing two CH2-CH3 chains. The dimer is typically about 54k Da. An “Fc monomer” is generally half the size of the dimer (e.g., about 27k Da). Methods for generating Fc dimers and monomers are described in Wang et al. Engineering soluble monomeric IgG1 Fc with significantly decreased non-specific binding. Front. Immunol. (2017) 8:1545; Ying et al. Soluble monomeric IgG1 Fc. J. Biol Chem (2012) 287(23): 19399-408, each of which is incorporated herein by reference in its entirety. In some embodiments, the Fc fragment has a polypeptide sequence having at least 80%, 85%, 90%, 91 %, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, or 100% sequence identity to SEQ ID NO: 13 (human IgG1 hinge-Fc) below: DKTHTCPPCPAPEAAGGPSVFLFPPKPKDTLMISRTPEVTCVVVDVSHEDPEVKF NWYVDGVEVHNAKTKPREEQYNSTYRVVSVLTVLHQDWLNGKEYKCKVSNKALPAPIEKT ISKAKGQPREPQVYTLPPSREEMTKNQVSLTCLVKGFYPSDIAVEWESNGQPENNYKTTP PVLDSDGSFFLYSKLTVDKSRWQQGNVFSCSVMHEALHNHYTQKSLSLSPGK (SEQ ID NO: 13). In some embodiments, the Fc fragment is a variant of a human IgG Fc region. In some embodiments, the Fc fragment is a variant of human IgG Fc comprising one or more amino acid substitutions in the CH2 and / or CH3 domains. In some embodiments, the carrier polypeptide (Y) is an Fc fragment generated from the heavy chain constant region of an immunoglobulin, an Fc monomer, an Fc dimer, or fragments thereof. In some embodiments, the carrier polypeptide (Y) Fc is conjugated to an antibody fragment comprising an antigen-binding region (e.g., nanobody, scFv, VHH) to form an engineered antibody. In some embodiments, the carrier polypeptide (Y) Fc is conjugated to an antigen to form an Fc-antigen fusion. In various embodiments, the Fc fragment is conjugated to polypeptide B at a cysteine residue on the Fc fragment. 1.1.6 Peptide-Peptide Linker In some embodiments, the carrier polypeptide (i.e., Y of Formula I) and the TSHR polypeptides (i.e., B of Formula I) are connected to B via a linker or linking sequence. In some embodiments, the linker is non-peptidic linking moiety. In some embodiments, the carrier polypeptide is fused directly to the TSHR polypeptide. In some embodiment, the carrier polypeptide is fused indirectly to B via, for example, Attorney Ref: 92VF-350823-WO Client Ref: 021WO a spacer domain. In some embodiment, the N-terminal of the carrier polypeptide is fused to the C- terminal of the TSHR polypeptide. In some embodiment, the C-terminal of the carrier polypeptide is fused to the N-terminal of the TSHR polypeptide. In some embodiments, the carrier polypeptide and the TSHR polypeptide may be connected via a linking sequence including one or more peptides. In some embodiments, the linking sequence may be polypeptides having 5 to 30 peptides. For example, the linking sequences may include (GGGGS)x, wherein x is about 1 to about 10. In some embodiments, the linking sequence may include GGGGS (SEQ ID NO: 41), GGGGSGGGGS (SEQ ID NO: 42), GGGGSGGGGSGGGGS (SEQ ID NO: 16), or GGGGSGGGGSGGGGSGGGGS (SEQ ID NO: 43). In some embodiments, the linking sequence may consist essentially of one of SEQ ID NOs: 16, 41-43. In some embodiments, the linking sequence may include SEQ ID NO: 16. In some embodiments, the linking sequence may consist essentially of SEQ ID NO: 16. 1.1.7 Exemplary LYTACs The examples described herein show specific, non-limiting, ASGPR binding compounds having chemoselective ligation group. For example, in some embodiments, provided is a conjugate (i.e., LYTAC) of Formula: In some embodiments, provided is a conjugate (i.e., LYTAC) of Formula: HO OO OB , m is 4 to 6; Attorney Ref: 92VF-350823-WO Client Ref: 021WO Y is a carrier polypeptide connected to B, wherein the carrier polypeptide is HSA comprising SEQ ID NO: 15; and B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody, the TSHR polypeptide comprising SEQ ID NO: 6. In some embodiments, provided is a conjugate (i.e., LYTAC) of Formula: HO HNO HO B . m is 4 to 6; Y is a carrier polypeptide connected to B, wherein the carrier polypeptide is HSA comprising SEQ ID NO: 15; and B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody, the TSHR polypeptide comprising SEQ ID NO: 6. In some embodiments, provided is a conjugate (i.e., LYTAC) of Formula:

[0008] Attorney Ref: 92VF-350823-WO Client Ref: 021WO OOHN O O O B , m is 4 to 6; Y is a carrier polypeptide connected to B, wherein the carrier polypeptide is HSA comprising SEQ ID NO: 15; and B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody, the TSHR polypeptide comprising SEQ ID NO: 6. In some embodiments, provided is a conjugate (i.e., LYTAC) of Formula: HO HO B , m is 4 to 6; Attorney Ref: 92VF-350823-WO Client Ref: 021WO Y is a carrier polypeptide connected to B, wherein the carrier polypeptide is HSA comprising SEQ ID NO: 15; and B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody, the TSHR polypeptide comprising SEQ ID NO: 6. In some embodiments, provided is a conjugate (i.e., LYTAC) of Formula: HO OO OHO NH B m is 4 to 6; Y is a carrier polypeptide connected to B, wherein the carrier polypeptide is HSA comprising SEQ ID NO: 15; B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody, comprising SEQ ID NO: 6; and Y is connected to B via a linking sequence comprising GGGGSGGGGSGGGGS (SEQ ID NO: 16). In some embodiments, provided is a conjugate (i.e., LYTAC) of Formula:

[0009] Attorney Ref: 92VF-350823-WO Client Ref: 021WO HO HNO HO B m is 4 to 6; Y is a carrier polypeptide connected to B, wherein the carrier polypeptide is HSA comprising SEQ ID NO: 15; B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody, comprising SEQ ID NO: 6; and Y is connected to B via a linking sequence comprising GGGGSGGGGSGGGGS (SEQ ID NO: 16). In some embodiments, provided is a conjugate (i.e., LYTAC) of Formula: O B Attorney Ref: 92VF-350823-WO Client Ref: 021WO wherein: m is 4 to 6; Y is a carrier polypeptide connected to B, wherein the carrier polypeptide is HSA comprising SEQ ID NO: 15; B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody, comprising SEQ ID NO: 6; and Y is connected to B via a linking sequence comprising GGGGSGGGGSGGGGS (SEQ ID NO: 16). In some embodiments, provided is a conjugate (i.e., LYTAC) of Formula: HO HO HO B m is 4 to 6; Y is a carrier polypeptide connected to B, wherein the carrier polypeptide is HSA comprising SEQ ID NO: 15; B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody, comprising SEQ ID NO: 6; and Y is connected to B via a linking sequence comprising GGGGSGGGGSGGGGS (SEQ ID NO: 16). Attorney Ref: 92VF-350823-WO Client Ref: 021WO 1.2 Pharmaceutical Compositions In another embodiment, provided herein are pharmaceutical compositions including one or more bifunctional molecules (e.g., conjugates) disclosed herein and a pharmaceutically acceptable carrier. In some embodiments, the pharmaceutical compositions provided herein contain therapeutically effective amounts of one or more of the conjugates provided herein, and optionally one or more additional prophylactic or therapeutic agents, in a pharmaceutically acceptable carrier. Pharmaceutical carriers suitable for administration of the conjugates provided herein include any such carriers known to those skilled in the art to be suitable for the particular mode of administration. The conjugates described herein can be formulated as the sole pharmaceutically active ingredient in the composition or can be combined with other active ingredients. In some embodiments, the conjugate is formulated into one or more suitable pharmaceutical preparations, such as solutions, suspensions, powders, sustained release formulations or elixirs in sterile solutions or suspensions for parenteral administration, or as transdermal patch preparation and dry powder inhalers. In compositions provided herein, a conjugate described herein may be mixed with a suitable pharmaceutical carrier. The concentration of the conjugate in the compositions can, for example, be effective for delivery of an amount, upon administration, that treats, prevents, or ameliorates a condition or disorder described herein or a symptom thereof. In some embodiments, the pharmaceutical compositions provided herein are formulated for single dosage administration. To formulate a composition, the weight fraction of conjugate is dissolved, suspended, dispersed or otherwise mixed in a selected carrier at an effective concentration such that the treated condition is relieved, prevented, or one or more symptoms are ameliorated. Concentrations of the conjugate in a pharmaceutical composition provided herein will depend on, e.g., the physicochemical characteristics of the conjugate, the dosage schedule, and amount administered as well as other factors known to those of skill in the art. Pharmaceutical compositions described herein are provided for administration to a subject, for example, humans or animals (e.g., mammals) in unit dosage forms, such as sterile parenteral (e.g., intravenous) solutions or suspensions containing suitable quantities of the compounds or pharmaceutically acceptable derivatives thereof. Pharmaceutical compositions are also provided for administration to humans and animals in unit dosage form, including oral or nasal solutions or suspensions and oil-water emulsions containing suitable quantities of a conjugate or pharmaceutically Attorney Ref: 92VF-350823-WO Client Ref: 021WO acceptable derivatives thereof. The conjugate is, In some embodiments, formulated and administered in unit-dosage forms or multiple-dosage forms. Unit-dose forms as used herein refers to physically discrete units suitable for human or animal (e.g., mammal) subjects and packaged individually as is known in the art. Each unit-dose contains a predetermined quantity of a conjugate sufficient to produce the desired therapeutic effect, in association with the required pharmaceutical carrier, vehicle or diluent. Examples of unit-dose forms include ampoules and syringes and individually packaged capsules. Unit-dose forms can be administered in fractions or multiples thereof. A multiple-dose form is a plurality of identical unit- dosage forms packaged in a single container to be administered in segregated unit-dose form. Examples of multiple-dose forms include vials, bottles of capsules or bottles. Hence, in specific aspects, multiple dose form is a multiple of unit-doses which are not segregated in packaging. In some embodiments, the conjugates herein are in a liquid pharmaceutical formulation. Liquid pharmaceutically administrable formulations can, for example, be prepared by dissolving, dispersing, or otherwise mixing a conjugate and optional pharmaceutical adjuvants in a carrier, such as, for example, water, saline, aqueous dextrose, glycerol, glycols, and the like, to thereby form a solution or suspension. In some embodiments, a pharmaceutical composition provided herein to be administered can also contain minor amounts of nontoxic auxiliary substances such as wetting agents, emulsifying agents, solubilizing agents, and pH buffering agents and the like. Actual methods of preparing such dosage forms are known, or will be apparent, to those skilled in this art; for example, see, e.g., Remington: The Science and Practice of Pharmacy (2012) 22nded., Pharmaceutical Press, Philadelphia, PA Dosage forms or compositions containing antibody in the range of 0.005% to 100% with the balance made up from non-toxic carrier can be prepared. Parenteral administration, in some embodiments, is characterized by injection, either subcutaneously, intramuscularly or intravenously is also contemplated herein. Injectables can be prepared in conventional forms, either as liquid solutions or suspensions, solid forms suitable for solution or suspension in liquid prior to injection, or as emulsions. The injectables, solutions and emulsions also contain one or more excipients. Suitable excipients are, for example, water, saline, dextrose, glycerol or ethanol. Other routes of administration may include, enteric administration, intracerebral administration, nasal administration, intraarterial administration, intracardiac administration, intraosseous infusion, intrathecal administration, and intraperitoneal administration. Preparations for parenteral administration include sterile solutions ready for injection, sterile dry soluble products, such as lyophilized powders, ready to be combined with a solvent just prior to use, including hypodermic tablets, sterile suspensions ready for injection, sterile dry insoluble products ready Attorney Ref: 92VF-350823-WO Client Ref: 021WO to be combined with a vehicle just prior to use and sterile emulsions. The solutions can be either aqueous or nonaqueous. If administered intravenously, suitable carriers include physiological saline or phosphate buffered saline (PBS), and solutions containing thickening and solubilizing agents, such as glucose, polyethylene glycol, and polypropylene glycol and mixtures thereof. Pharmaceutically acceptable carriers used in parenteral preparations include aqueous vehicles, nonaqueous vehicles, antimicrobial agents, isotonic agents, buffers, antioxidants, local anesthetics, suspending and dispersing agents, emulsifying agents, sequestering or chelating agents and other pharmaceutically acceptable substances. Pharmaceutical carriers also include ethyl alcohol, polyethylene glycol and propylene glycol for water miscible vehicles; and sodium hydroxide, hydrochloric acid, citric acid or lactic acid for pH adjustment. In some embodiments, intravenous or intraarterial infusion of a sterile aqueous solution containing a conjugate described herein is an effective mode of administration. Another embodiment is a sterile aqueous or oily solution or suspension containing a conjugate described herein injected as necessary to produce the desired pharmacological effect. In some embodiments, the pharmaceutical formulations are lyophilized powders, which can be reconstituted for administration as solutions, emulsions and other mixtures. They can also be reconstituted and formulated as solids or gels. The lyophilized powder is prepared by dissolving a conjugate provided herein, in a suitable solvent. In some embodiments, the lyophilized powder is sterile. Suitable solvents can contain an excipient which improves the stability or other pharmacological component of the powder or reconstituted solution, prepared from the powder. Excipients that can be used include, but are not limited to, dextrose, sorbitol, fructose, corn syrup, xylitol, glycerin, glucose, sucrose or other suitable agent. A suitable solvent can also contain a buffer, such as citrate, sodium or potassium phosphate or other such buffer known to those of skill in the art at, In some embodiments, about neutral pH. Subsequent sterile filtration of the solution followed by lyophilization under standard conditions known to those of skill in the art provides an example of a formulation. In some embodiments, the resulting solution will be apportioned into vials for lyophilization. Lyophilized powder can be stored under appropriate conditions, such as at about 4 °C to room temperature. Attorney Ref: 92VF-350823-WO Client Ref: 021WO Reconstitution of this lyophilized powder with water for injection provides a formulation for use in parenteral administration. For reconstitution, the lyophilized powder is added to sterile water or other suitable carrier. In some embodiments, the conjugates provided herein can be formulated for local administration or topical application, such as for topical application to the skin and mucous membranes, such as in the eye, in the form of gels, creams, and lotions and for application to the eye or for intracisternal or intraspinal application. Topical administration is contemplated for transdermal delivery and also for administration to the eyes or mucosa, or for inhalation therapies. Nasal solutions of the active compound alone or in combination with other pharmaceutically acceptable excipients can also be administered. 1.3 Methods of Use Binding of the ligand moiety of the bifunctional molecule to the ASGPR can trigger internalization and lysosomal degradation of a bound target anti-TSHR autoantibody. In some embodiments, the bifunctional molecule is a conjugate of a protein that includes the polypeptide that specifically binds anti-TSHR autoantibody and a linked ligand moiety. The bifunctional molecules of this disclosure find use in reducing levels of the extracellular target molecule anti-TSHR autoantibody in a biological system or sample. The biological system can be a human subject. The methods of using the conjugates described herein can thus remove anti-TSHR autoantibodies from the extracellular space (the extracellular milieu) of a cell in the biological system by sequestering the target protein in the cell’s lysosome and degrading the target anti-TSHR autoantibodies. Removal of a target protein may refer to reduction of the amount of, or depletion of, the target protein from the extracellular space, or the extracellular milieu. In some embodiments, the biological system or sample is a cellular sample. The term “sample” refers to an aliquot or portion taken from a source and / or provided for analysis or processing. In some embodiments, a sample is from a biological source such as a tissue, cell or component part (e.g., a body fluid, including but not limited to blood, mucus, lymphatic fluid, synovial fluid, cerebrospinal fluid, saliva, amniotic fluid, amniotic cord blood, urine, vaginal fluid and semen). In some embodiments, a sample may be or include a homogenate, lysate or extract prepared from a whole organism or a subset of its tissues, cells or component parts, or a fraction or portion thereof, including but not limited to, for example, plasma, serum, spinal fluid, lymph fluid, the external sections of the skin, respiratory, intestinal, and genitourinary tracts, tears, saliva, milk, blood cells, tumors, or organs. In some embodiments, a sample is or includes a medium, such as a nutrient broth or gel, which may contain cellular components, such as proteins. In some embodiments, a “primary” sample is an aliquot of the Attorney Ref: 92VF-350823-WO Client Ref: 021WO source. In some embodiments, a primary sample is subjected to one or more processing (e.g., separation, purification, etc.) steps to prepare a sample for analysis or other use. 1.3.1 Methods of Treatment Provided herein are methods of treating a disease or disorder caused by the target anti-TSHR autoantibody in a human subject. The present disclosure thus provides methods related to using the bifunctional molecules, conjugates and compositions of this disclosure for therapeutic treatment of Graves’ disease (GD) or thyroid eye disease (TED). These conditions can be treated according to the subject methods by depletion of anti-TSHR autoantibodies (e.g., M22, K1-18, K1-70, and other TSH Receptor Binding Antibodies or TRAbs) by degradation through the lysosomal pathway. In some embodiments, the method of treating GD or TED includes administering to a subject, e.g., a human subject in need thereof, an effective amount of a bifunctional molecule, such as a conjugate having formula (I) as described herein, or pharmaceutically acceptable salt thereof, or a pharmaceutical composition including the bifunctional molecule (e.g., as described herein). The terms “administer”, “administration”, or “administering” refer to the act of injecting or otherwise physically delivering a substance (e.g., a conjugate or pharmaceutical composition provided herein) to a subject or a patient (e.g., human), such as by mucosal, topical, intradermal, parenteral, intravenous, intramuscular delivery and / or any other method of physical delivery described herein or known in the art. In some embodiments, administration is oral. In some embodiments, administration is by subcutaneous injection. In some embodiments, administration is by intravenous infusion. The term “treating” refers to partially or completely alleviating, ameliorating, improving, relieving, delaying onset of, inhibiting progression of, reducing severity of, and / or reducing incidence of one or more symptoms or features of a particular disease, disorder, and / or condition (e.g., myasthenia gravis). Treatment may be administered to a subject who does not exhibit signs of a disease, disorder, and / or condition and / or to a subject who exhibits only early signs of a disease, disorder, and / or condition for the purpose of decreasing the risk of developing pathology associated with the disease, disorder, and / or condition. A treatment or preventive effect is evident when there is a significant improvement, often statistically significant, in one or more parameters of disease status, or by a failure to worsen or to develop symptoms where they would otherwise be anticipated. As an example, a favorable change of at least 10% in a measurable parameter of disease, and at least 20%, 30%, 40%, 50% or more can be indicative of effective treatment. Efficacy for a given compound or composition can also be judged using Attorney Ref: 92VF-350823-WO Client Ref: 021WO an experimental animal model for the given disease as known in the art. When using an experimental animal model, efficacy of treatment is evidenced when a statistically significant modulation in a marker or symptom is observed. The terms “effective amount” or “therapeutically effective amount” refer to an amount of a therapeutic (e.g., a conjugate or pharmaceutical composition provided herein) which is sufficient to treat, diagnose, prevent, delay the onset of, reduce and / or ameliorate the severity and / or duration of a given condition, disorder or disease (e.g., myasthenia gravis) and / or a symptom related thereto. These terms also encompass an amount necessary for the reduction, slowing, or amelioration of the advancement or progression of a given disease, reduction, slowing, or amelioration of the recurrence, development or onset of a given disease, and / or to improve or enhance the prophylactic or therapeutic effect(s) of another therapy or to serve as a bridge to another therapy. In some embodiments, “effective amount” as used herein also refers to the amount of a conjugate described herein to achieve a specified result. The term “treatment dose” refers to one or more doses of a therapeutic agent administered in the course of addressing or alleviating a therapeutic indication. Treatment doses may be adjusted to maintain a desired concentration or level of activity of a therapeutic agent in a body fluid or biological system. In some embodiments, the treatment dose is from about 0.1 mg / kg to about 100 mg / kg. In some embodiments, the treatment dose is from about 1 mg / kg to about 10 mg / kg. In some embodiments, the treatment dose is 1 mg / kg. In some embodiments, the treatment dose is 3 mg / kg. In some embodiments, the treatment dose is 5 mg / kg. In some embodiments, the treatment dose is 10 mg / kg. A bifunctional molecule of this disclosure and additional therapeutic agent(s) and / or therapies for GD or TED can be administered in combination. Such combinations may be in the same composition, or the additional therapeutic agents or therapies can be administered as part of a separate composition or by another method described herein. During administration of the compounds and conjugates according to methods of this disclosure, subjects may receive standard of care (SOC) therapy for GD or TED. Standard of care therapies include, but are not limited to, antithyroid drug treatment, radioactive iodine treatment, and surgery (i.e., thyroidectomy). The terms “subject” and “patient” are used interchangeably. A subject can be a mammal such as a non-primate (e.g., cows, pigs, horses, cats, dogs, goats, rabbits, rats, mice, etc.) or a primate (e.g., monkey and human), for example a human. In some embodiments, the subject is a mammal, e.g., a human, diagnosed with a disease or disorder provided herein. In another embodiment, the subject is a Attorney Ref: 92VF-350823-WO Client Ref: 021WO mammal, e.g., a human, at risk of developing a disease or disorder provided herein. In some embodiments, the subject is human. Patients treated with bifunctional molecule according to the methods of this disclosure may be screened prior to administration. The terms “patient”, “subject” and “individual” are used interchangeably herein. The term “screen” refers to a review or evaluation carried out for the purpose of selection or filtration. Patients may be screened to select individuals in need of treatment. In some embodiments, subjects are screened to select individuals most likely to respond favorably to treatment. 1.4 Definitions Unless otherwise indicated, the term “about” or “approximately” means an acceptable error for a particular value as determined by one of ordinary skill in the art, which depends in part on how the value is measured or determined. In some embodiments, the term “about” or “approximately” means within 1, 2, or 3 standard deviations. In some embodiments, the term “about” or “approximately” means within 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.5%, 0.4%, 0.3%, 0.25%, 0.2%, 0.1% or 0.05% of a given value or range. In some embodiments, where an integer is required, the term “about” means within plus or minus 10% of a given value or range, rounded either up or down to the nearest integer. As used herein, the phrases “for example,” “for instance,” “such as,” or “including” are meant to introduce examples that further clarify more general subject matter. These examples are provided only as an aid for understanding the disclosure, and are not meant to be limiting in any fashion. The publications discussed herein are provided solely for their disclosure prior to the filing date of the present application. Nothing herein is to be construed as an admission that the present disclosure is not entitled to antedate such publication by virtue of prior disclosure. Further, the dates of publication provided may be different from the actual publication dates which may need to be independently confirmed. The term “autoantibody” or “autoantibodies” refers to an antibody that recognizes, binds, or otherwise interacts with an antigen normally found in a subject, or a tissue or cell of a subject. Autoantibodies are abnormal antibodies which are generated by pathogenic B cells when targeting an individual’s own tissue. The term “autoimmunity” refers to the presence of antibodies (which are made by B lymphocytes) and T lymphocytes directed against normal components of a person (autoantigens). These components are called autoantigens or self-antigens and typically consist of proteins (or proteins complexed to nucleic acids). The antibodies and T lymphocytes that recognize autoantigens are called “autoantibodies” and “autoreactive T cells”. Attorney Ref: 92VF-350823-WO Client Ref: 021WO The terms “protein” and “polypeptide” are used interchangeably. Proteins may include moieties other than amino acids (e.g., may be glycoproteins, etc.) and / or may be otherwise processed or modified. Those of ordinary skill in the art will appreciate that a “protein” can be a complete protein chain as produced by a cell (with or without a signal sequence), or can be a protein portion thereof. Those of ordinary skill will appreciate that a protein can sometimes include more than one protein chain, for example non-covalently or covalently attached, e.g., linked by one or more disulfide bonds or associated by other means. In some embodiments, a polypeptide can occur as a single chain or as two or more associated chains, e.g., may be present as a multimer, e.g., dimer, a trimer. The terms also encompass an amino acid polymer that has been modified naturally or by intervention; for example, by disulfide bond formation, glycosylation, lipidation, acetylation, phosphorylation, or any other manipulation or modification. Also included within the definition are, for example, polypeptides containing one or more analogs of an amino acid, including but not limited to, unnatural amino acids, as well as other modifications known in the art. Polypeptides may contain L-amino acids, D-amino acids, or both and may contain any of a variety of amino acid modifications or analogs known in the art. Useful modifications include, e.g., terminal acetylation, amidation, methylation, etc. In some embodiments, proteins may include natural amino acids, non-natural amino acids, synthetic amino acids, and combinations thereof. An “antibody fragment” comprises a portion of an intact antibody, such as the antigen-binding or variable region of an intact antibody. Antibody fragments include, for example, Fv fragments, Fab fragments, F(ab’)2fragments, Fab’ fragments, scFv fragments, and VHH fragments. An “antigen” is a moiety or molecule that contains an epitope to which an antibody can specifically bind. As such, an antigen is also specifically bound by an antibody. An “epitope” is a term known in the art and refers to a localized region of an antigen to which an antibody can specifically bind. An epitope can be a linear epitope of contiguous amino acids or can include amino acids from two or more non-contiguous regions of the antigen. A “pharmaceutically acceptable excipient,” “pharmaceutically acceptable diluent,” “pharmaceutically acceptable carrier,” and “pharmaceutically acceptable adjuvant” means an excipient, diluent, carrier, and adjuvant that are useful in preparing a pharmaceutical composition that are generally safe, non-toxic and neither biologically nor otherwise undesirable, and include an excipient, diluent, carrier, and adjuvant that are acceptable for veterinary use as well as human pharmaceutical use. “A pharmaceutically acceptable excipient, diluent, carrier and adjuvant” as used in the specification and claims includes both one and more than one such excipient, diluent, carrier, and adjuvant. Attorney Ref: 92VF-350823-WO Client Ref: 021WO A “pharmaceutical composition” is meant to encompass a composition suitable for administration to a subject, such as a mammal, especially a human. In general, a “pharmaceutical composition” is sterile, and typically free of contaminants that are capable of eliciting an undesirable response within the subject (e.g., the compound(s) in the pharmaceutical composition is pharmaceutical grade). Pharmaceutical compositions can be designed for administration to subjects or patients in need thereof via a number of different routes of administration including oral, buccal, rectal, parenteral, intraperitoneal, intradermal, intracheal, intramuscular, subcutaneous, and the like. The term “pharmaceutically acceptable” means being approved by a regulatory agency of the Federal or a state government, or listed in the U.S. Pharmacopeia, European Pharmacopeia or other generally recognized Pharmacopeia for use in animals, and, more particularly in humans. The term “pharmaceutically acceptable salt” refers to those salts which are suitable for use in contact with the tissues of humans and lower animals without undue toxicity, irritation, allergic response and the like. Pharmaceutically acceptable salts are well known in the art. For example, S. M. Berge, et al. describes pharmaceutically acceptable salts in detail in J. Pharmaceutical Sciences, 66: 1-19 (1977). The salts can be prepared in situ during the final isolation and purification of the conjugate compounds, or separately by reacting the free base function or group of a compound with a suitable organic acid. Examples of pharmaceutically acceptable salts include, but are not limited to, nontoxic acid addition salts, or salts of an amino group formed with inorganic acids. Compounds are described using standard nomenclature. The compounds in any of the formulas described herein may be in the form of a racemate, enantiomer, mixture of enantiomers, diastereomer, mixture of diastereomers, tautomer, N-oxide, isomer; such as rotamer, as if each is specifically described unless specifically excluded by context. As used herein, the phrase “having the formula” or “having the structure” is not intended to be limiting and is used in the same way that the term “comprising” is commonly used. The term “independently selected from” is used herein to indicate that the recited elements, e.g., R groups or the like, can be identical or different. A dash (“-”) that is not between two letters or symbols is used to indicate a point of attachment for a substituent. For example, —(C═O)NH2is attached through carbon of the carbonyl (C═O) group. The present disclosure includes compounds (e.g., as described herein) with at least one desired isotopic substitution of an atom, at an amount above the natural abundance of the isotope, i.e., enriched. Isotopes are atoms having the same atomic number but different mass numbers, i.e., the same number of protons but a different number of neutrons. Attorney Ref: 92VF-350823-WO Client Ref: 021WO Examples of isotopes that can be incorporated into compounds of the disclosure include isotopes of hydrogen, carbon, nitrogen, oxygen, phosphorous, fluorine, chlorine and iodine such as2H,3H,11C,13C,14C,15N,18F31P,32P,35S,36Cl, and125I respectively. In one non-limiting embodiment, isotopically labelled compounds can be used in metabolic studies (with, for example14C), reaction kinetic studies (with, for example2H or3H), detection or imaging techniques, such as positron emission tomography (PET) or single-photon emission computed tomography (SPECT) including drug or substrate tissue distribution assays, or in treatment of patients. In particular, an18F labeled compound may be particularly desirable for PET or SPECT studies. Isotopically labeled compounds of this disclosure and prodrugs thereof can generally be prepared by carrying out the procedures disclosed in the schemes or in the examples and preparations described below by substituting a readily available isotopically labeled reagent for a non-isotopically labeled reagent. Isotopic substitutions, for example deuterium substitutions, can be partial or complete. Partial deuterium substitution means that at least one hydrogen is substituted with deuterium. In some embodiments, the isotope is 90, 95 or 99% or more enriched in an isotope at any location of interest. In one non-limiting embodiment, deuterium is 90, 95 or 99% enriched at a desired location. In some embodiments, the substitution of a hydrogen atom for a deuterium atom can be provided in any compound of Formulas described herein. In one non-limiting embodiment, the substitution of a hydrogen atom for a deuterium atom occurs within one or more groups selected from any of R1, R2, R3, R4, R6, R11, R21, R22, R23, R24, R25R, R’, and R’’ etc. For example, when any of the groups are, or contain for example through substitution, methyl, ethyl, or methoxy, the alkyl residue may be deuterated (in non- limiting embodiments, CDH2, CD2H, CD3, CH2CD3, CD2CD3, CHDCH2D, CH2CD3, CHDCHD2, OCDH2, OCD2H, or OCD3etc.). In certain other embodiments, when two substituents are combined to form a cycle the unsubstituted carbons may be deuterated. “Aliphatic” refers to a saturated or unsaturated, straight, branched, or cyclic hydrocarbon. “Aliphatic” is intended herein to include, but is not limited to, alkyl, alkenyl, alkynyl, cycloalkyl, cycloalkenyl, and cycloalkynyl moieties, and thus incorporates each of these definitions. In one embodiment, “aliphatic” is used to indicate those aliphatic groups having 1-20 carbon atoms. The aliphatic chain can be, for example, mono-unsaturated, di-unsaturated, tri-unsaturated, or polyunsaturated, or alkynyl. Unsaturated aliphatic groups can be in a cis or trans configuration. In one embodiment, the aliphatic group contains from 1 to about 12 carbon atoms, more generally from 1 to about 6 carbon atoms or from 1 to about 4 carbon atoms. In one embodiment, the aliphatic group contains from 1 to about 8 carbon atoms. In some embodiments, the aliphatic group is C1-C2, C1-C3, C1-C4, C1-C5or C1-C6. The specified ranges as used herein indicate an aliphatic group having each member of the range described as Attorney Ref: 92VF-350823-WO Client Ref: 021WO an independent species. For example, the term C1-C6aliphatic as used herein indicates a straight or branched alkyl, alkenyl, or alkynyl group having from 1, 2, 3, 4, 5, or 6 carbon atoms and is intended to mean that each of these is described as an independent species. For example, the term C1-C4aliphatic as used herein indicates a straight or branched alkyl, alkenyl, or alkynyl group having from 1, 2, 3, or 4 carbon atoms and is intended to mean that each of these is described as an independent species. In one embodiment, the aliphatic group is substituted with one or more functional groups that results in the formation of a stable moiety. “Alkyl” is a branched or straight chain saturated aliphatic hydrocarbon group. In one non-limiting embodiment, the alkyl group contains from 1 to about 12 carbon atoms, more generally from 1 to about 6 carbon atoms or from 1 to about 4 carbon atoms. In one non-limiting embodiment, the alkyl contains from1 to about 8 carbon atoms. In some embodiments, the alkyl is C1-C2, C1-C3, C1-C4, C1-C5, or C1-C6. Thespecified ranges as used herein indicate an alkyl group having each member of the range described as an independent species. For example, the term C1-C6alkyl as used herein indicates a straight or branched alkyl group having from 1, 2, 3, 4, 5, or 6 carbon atoms and is intended to mean that each of these is described as an independent species and therefore each subset is considered separately disclosed. For example, the term C1-C4alkyl as used herein indicates a straight or branched alkyl group having from 1, 2, 3, or 4 carbon atoms and is intended to mean that each of these is described as an independent species. Examples of alkyl include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, t-butyl, n-pentyl, isopentyl, tert-pentyl, neopentyl, n-hexyl, 2-methylpentane, 3-methylpentane, 2,2-dimethylbutane, and 2,3-dimethylbutane. In an alternative embodiment, the alkyl group is optionally substituted. The term “alkyl” also encompasses cycloalkyl or carbocyclic groups. For example, when a term is used that includes “alk” then “cycloalkyl” or “carbocyclic” can be considered part of the definition, unless unambiguously excluded by the context. For example, and without limitation, the terms alkyl, alkoxy, haloalkyl, etc. can all be considered to include the cyclic forms of alkyl, unless unambiguously excluded by context. “Alkenyl” is a linear or branched aliphatic hydrocarbon groups having one or more carbon- carbon double bonds that may occur at a stable point along the chain. The specified ranges as used herein indicate an alkenyl group having each member of the range described as an independent species, as described above for the alkyl moiety. Examples of alkenyl radicals include, but are not limited to ethenyl, propenyl, allyl, propenyl, butenyl and 4-methylbutenyl. The term “alkenyl” also embodies “cis” and “trans” alkenyl geometry, or alternatively, “E” and “Z” alkenyl geometry. In an alternative embodiment, the alkenyl group is optionally substituted. The term “Alkenyl” also encompasses cycloalkyl or carbocyclic groups possessing at least one point of unsaturation. Attorney Ref: 92VF-350823-WO Client Ref: 021WO “Alkynyl” is a branched or straight chain aliphatic hydrocarbon group having one or more carbon-carbon triple bonds that may occur at any stable point along the chain. The specified ranges as used herein indicate an alkynyl group having each member of the range described as an independent species, as described above for the alkyl moiety. Examples of alkynyl include, but are not limited to, ethynyl, propynyl, 1-butynyl, 2-butynyl, 3-butynyl, 1-pentynyl, 2-pentynyl, 3-pentynyl, 4-pentynyl, 1- hexynyl, 2-hexynyl, 3-hexynyl, 4-hexynyl and 5-hexynyl. In an alternative embodiment, the alkynyl group is optionally substituted. The term “Alkynyl” also encompasses cycloalkyl or carbocyclic groups possessing at least one triple bond. “Alkylene” is a bivalent saturated hydrocarbon. Alkylenes, for example, can be a 1, 2, 3, 4, 5, 6, 7 to 8 carbon moiety, 1 to 6 carbon moiety, or an indicated number of carbon atoms, for example C1- C2alkylene, C1-C3alkylene, C1-C4alkylene, C1-C6alkylene, or C1-C6alkylene. “Alkenylene” is a bivalent hydrocarbon having at least one carbon-carbon double bond. Alkenylenes, for example, can be a 2 to 8 carbon moiety, 2 to 6 carbon moiety, or an indicated number of carbon atoms, for example C2-C4alkenylene. “Alkynylene” is a bivalent hydrocarbon having at least one carbon-carbon triple bond. Alkynylenes, for example, can be a 2 to 8 carbon moiety, 2 to 6 carbon moiety, or an indicated number of carbon atoms, for example C2-C4alkynylene. The term “amino” refers to the group -NRR’ wherein R and R’ are independently hydrogen or nonhydrogen substituents, with nonhydrogen substituents including, for example, alkyl, aryl, alkenyl, aralkyl, and substituted and / or heteroatom-containing variants thereof. “Chain” indicates a linear chain to which all other chains, long or short or both, may be regarded as being pendant. Where two or more chains could equally be considered to be the main chain, “chain” refers to the one which leads to the simplest representation of the molecule. “Cycloalkyl” refers to cyclic alkyl groups of from 3 to 10 carbon atoms having single or multiple cyclic rings including fused, bridged, and spiro ring systems. Examples of suitable cycloalkyl groups include, for instance, cyclopropyl, cyclobutyl, cyclopentyl, cyclooctyl and the like. Such cycloalkyl groups include, by way of example, single ring structures such as cyclopropyl, cyclobutyl, cyclopentyl, cyclooctyl, and the like, or multiple ring structures such as adamantanyl, and the like. “Halo” and “halogen” refers to fluorine, chlorine, bromine or iodine. “Haloalkyl” is a branched or straight-chain alkyl groups substituted with 1 or more halo atoms described above, up to the maximum allowable number of halogen atoms. Examples of haloalkyl groups Attorney Ref: 92VF-350823-WO Client Ref: 021WO include, but are not limited to, fluoromethyl, difluoromethyl, trifluoromethyl, chloromethyl, dichloromethyl, trichloromethyl, pentafluoroethyl, heptafluoropropyl, difluorochloromethyl, dichlorofluoromethyl, difluoroethyl, difluoropropyl, dichloroethyl and dichloropropyl. “Perhaloalkyl” means an alkyl group having all hydrogen atoms replaced with halogen atoms. Examples include but are not limited to, trifluoromethyl and pentafluoroethyl. “Haloalkoxy” indicates a haloalkyl group as defined herein attached through an oxygen bridge (oxygen of an alcohol radical). The term “heteroaliphatic” refers to an aliphatic moiety that contains at least one heteroatom in the chain, for example, an amine, carbonyl, carboxy, oxo, thio, phosphate, phosphonate, nitrogen, phosphorus, silicon, or boron atoms in place of a carbon atom. In one embodiment, the only heteroatom is nitrogen. In one embodiment, the only heteroatom is oxygen. In one embodiment, the only heteroatom is sulfur. “Heteroaliphatic” is intended herein to include, but is not limited to, heteroalkyl, heteroalkenyl, heteroalkynyl, heterocycloalkyl, heterocycloalkenyl, and heterocycloalkynyl moieties. In one embodiment, “heteroaliphatic” is used to indicate a heteroaliphatic group (cyclic, acyclic, substituted, unsubstituted, branched or unbranched) having 1-20 carbon atoms. In one embodiment, the heteroaliphatic group is optionally substituted in a manner that results in the formation of a stable moiety. Nonlimiting examples of heteroaliphatic moieties are polyethylene glycol, polyalkylene glycol, amide, polyamide, polylactide, polyglycolide, thioether, ether, alkyl-heterocycle-alkyl, —O-alkyl-O-alkyl, alkyl- O-haloalkyl, etc. “Heterocycloalkyl” is an alkyl group as defined herein substituted with a heterocyclo group as defined herein. “Arylalkyl” is an alkyl group as defined herein substituted with an aryl group as defined herein. “Heteroarylalkyl” is an alkyl group as defined herein substituted with a heteroaryl group as defined herein. The term “alkynyl” refers to a linear or branched hydrocarbon group of 2 to 24 carbon atoms containing at least one triple bond, such as ethynyl, n-propynyl, and the like. Generally, although again not necessarily, alkynyl groups herein may contain 2 to about 18 carbon atoms, and such groups may further contain 2 to 12 carbon atoms. The term “lower alkynyl” intends an alkynyl group of 2 to 6 carbon atoms. The term “substituted alkynyl” refers to alkynyl substituted with one or more substituent groups, and the terms “heteroatom-containing alkynyl” and “heteroalkynyl” refer to alkynyl in which at least one carbon atom is replaced with a heteroatom. If not otherwise indicated, the terms “alkynyl” and “lower Attorney Ref: 92VF-350823-WO Client Ref: 021WO alkynyl” include linear, branched, unsubstituted, substituted, and / or heteroatom-containing alkynyl and lower alkynyl, respectively. The term aryl” refers to a radical of a monocyclic or polycyclic (e.g., bicyclic or tricyclic) 4n+2 aromatic ring system (e.g., having 6, 10, or 14 π electrons shared in a cyclic array) having 6-14 ring carbon atoms and zero heteroatoms provided in the aromatic ring system (“C6-14aryl”). In some embodiments, an aryl group has 6 ring carbon atoms (“C6aryl”; e.g., phenyl). In some embodiments, an aryl group has 10 ring carbon atoms (“C10aryl”; e.g., naphthyl such as 1-naphthyl and 2-naphthyl). In some embodiments, an aryl group has 14 ring carbon atoms (“C14 aryl”; e.g., anthracyl). “Aryl” also includes ring systems wherein the aryl ring, as defined above, is fused with one or more carbocyclyl or heterocyclyl groups wherein the radical or point of attachment is on the aryl ring, and in such instances, the number of carbon atoms continue to designate the number of carbon atoms in the aryl ring system. The one or more fused carbocyclyl or heterocyclyl groups can be 4 to 7 or 5 to 7-membered saturated or partially unsaturated carbocyclyl or heterocyclyl groups that optionally contain 1, 2, or 3 heteroatoms independently selected from nitrogen, oxygen, phosphorus, sulfur, silicon and boron, to form, for example, a 3,4-methylenedioxyphenyl group. In one non-limiting embodiment, aryl groups are pendant. An example of a pendant ring is a phenyl group substituted with a phenyl group. In an alternative embodiment, the aryl group is optionally substituted as described above. In some embodiments, the aryl group is an unsubstituted C6-14aryl. In some embodiments, the aryl group is a substituted C6-14aryl. An aryl group may be optionally substituted with one or more functional groups that include but are not limited to, halo, hydroxy, nitro, amino, cyano, haloalkyl, aryl, heteroaryl, and heterocyclo. The term “heterocyclyl” (or “heterocyclo”) includes saturated, and partially saturated heteroatom- containing ring radicals, where the heteroatoms may be selected from nitrogen, sulfur and oxygen. Heterocyclic rings comprise monocyclic 3-8 membered rings, as well as 5-16 membered bicyclic ring systems (which can include bridged fused and spiro-fused bicyclic ring systems). It does not include rings containing —O—O—.—O—S— or —S—S— portions. Said “heterocyclyl” group may be optionally substituted, for example, with 1, 2, 3, 4 or more substituents that include but are not limited to, hydroxyl, Boc, halo, haloalkyl, cyano, alkyl, aralkyl, oxo, alkoxy, and amino. Examples of saturated heterocyclo groups include saturated 3- to 6-membered heteromonocyclic groups containing 1 to 4 nitrogen atoms [e.g. pyrrolidinyl, imidazolidinyl, piperidinyl, pyrrolinyl, piperazinyl]; saturated 3 to 6-membered heteromonocyclic group containing 1 to 2 oxygen atoms and 1 to 3 nitrogen atoms [e.g. morpholinyl]; saturated 3 to 6-membered heteromonocyclic group containing 1 to 2 sulfur atoms and 1 to 3 nitrogen atoms [e.g., thiazolidinyl]. Examples of partially saturated heterocyclyl radicals include but are not limited to, dihydrothienyl, dihydropyranyl, dihydrofuryl, and dihydrothiazolyl. Examples of partially Attorney Ref: 92VF-350823-WO Client Ref: 021WO saturated and saturated heterocyclo groups include but are not limited to, pyrrolidinyl, imidazolidinyl, piperidinyl, pyrrolinyl, pyrazolidinyl, piperazinyl, morpholinyl, tetrahydropyranyl, thiazolidinyl, dihydrothienyl, 2,3-dihydro-benzo[1,4]dioxanyl, indolinyl, isoindolinyl, dihydrobenzothienyl, dihydrobenzofuryl, isochromanyl, chromanyl, 1,2-dihydroquinolyl, 1,2,3,4-tetrahydro-isoquinolyl, 1,2,3,4-tetrahydro-quinolyl, 2,3,4,4a,9,9a-hexahydro-1H-3-aza-fluorenyl, 5,6,7-trihydro-1,2,4- triazolo[3,4-a]isoquinolyl, 3,4-dihydro-2H-benzo[1,4]oxazinyl, benzo[1,4]dioxanyl, 2,3-dihydro-1H-1λ′- benzo[d]isothiazol-6-yl, dihydropyranyl, dihydrofuryl and dihydrothiazolyl. Heterocyclo groups also include radicals where heterocyclic radicals are fused / condensed with aryl or heteroaryl radicals: such as unsaturated condensed heterocyclic group containing 1 to 5 nitrogen atoms, for example, indoline, isoindoline, unsaturated condensed heterocyclic group containing 1 to 2 oxygen atoms and 1 to 3 nitrogen atoms, unsaturated condensed heterocyclic group containing 1 to 2 sulfur atoms and 1 to 3 nitrogen atoms, and saturated, partially unsaturated and unsaturated condensed heterocyclic group containing 1 to 2 oxygen or sulfur atoms. The term “heteroaryl” denotes aryl ring systems that contain one or more heteroatoms selected from O, N and S, wherein the ring nitrogen and sulfur atom(s) are optionally oxidized, and nitrogen atom(s) are optionally quarternized. Examples include but are not limited to, unsaturated 5 to 6 membered heteromonocyclyl groups containing 1 to 4 nitrogen atoms, such as pyrrolyl, imidazolyl, pyrazolyl, 2- pyridyl, 3-pyridyl, 4-pyridyl, pyrimidyl, pyrazinyl, pyridazinyl, triazolyl [e.g., 4H-1,2,4-triazolyl, IH- 1,2,3-triazolyl, 2H-1,2,3-triazolyl]; unsaturated 5- to 6-membered heteromonocyclic groups containing an oxygen atom, for example, pyranyl, 2-furyl, 3-furyl, etc.; unsaturated 5 to 6-membered heteromonocyclic groups containing a sulfur atom, for example, 2-thienyl, 3-thienyl, etc.; unsaturated 5- to 6-membered heteromonocyclic groups containing 1 to 2 oxygen atoms and 1 to 3 nitrogen atoms, for example, oxazolyl, isoxazolyl, oxadiazolyl [e.g., 1,2,4-oxadiazolyl, 1,3,4-oxadiazolyl, 1,2,5-oxadiazolyl]; unsaturated 5 to 6-membered heteromonocyclic groups containing 1 to 2 sulfur atoms and 1 to 3 nitrogen atoms, for example, thiazolyl, thiadiazolyl [e.g., 1,2,4-thiadiazolyl, 1,3,4-thiadiazolyl, 1,2,5-thiadiazolyl]. As used herein, the terms “may,” “optional,” “optionally,” or “may optionally” mean that the subsequently described circumstance may or may not occur, so that the description includes instances where the circumstance occurs and instances where it does not. For example, the phrase “optionally substituted” means that a non-hydrogen substituent may or may not be present on a given atom, and, thus, the description includes structures wherein a non-hydrogen substituent is present and structures wherein a non-hydrogen substituent is not present. The term “optionally substituted” denotes the substitution of a group herein by a moiety including, but not limited to, C1-C10alkyl, C2-C10alkenyl, C2-C10alkynyl, C3-C12cycloalkyl, C3- Attorney Ref: 92VF-350823-WO Client Ref: 021WO C12cycloalkenyl, C1-C12heterocycloalkyl, C3-C12heterocycloalkenyl, C1-C10alkoxy, aryl, aryloxy, heteroaryl, heteroaryloxy, amino, C1-C10alkylamino, C1-C10dialkylamino, arylamino, diarylamino, C1- C10alkylsulfonamino, arylsulfonamino, C1-C10alkylimino, arylimino, C1-C10alkylsulfonimino, arylsulfonimino, hydroxyl, halo, thio, C1-C10alkylthio, 113midazoli, C1-C10alkylsulfonyl, arylsulfonyl, acylamino, aminoacyl, aminothioacyl, amidino, guanidine, ureido, cyano, nitro, azido, acyl, thioacyl, acyloxy, carboxyl, and carboxylic ester. In one alternative embodiment any suitable group may be present on a “substituted” or “optionally substituted” position if indicated that forms a stable molecule and meets the desired purpose of the disclosure and includes, but is not limited to, e.g., halogen (which can independently be F, Cl, Br or I); cyano; hydroxyl; nitro; azido; alkanoyl (such as a C2-C6alkanoyl group); carboxamide; alkyl, cycloalkyl, alkenyl, alkynyl, alkoxy, aryloxy such as phenoxy; thioalkyl including those having one or more thioether linkages; alkylsulfinyl; alkylsulfonyl groups including those having one or more sulfonyl linkages; aminoalkyl groups including groups having more than one N atoms; aryl (e.g., phenyl, biphenyl, naphthyl, or the like, each ring either substituted or unsubstituted); arylalkyl having for example, 1 to 3 separate or fused rings and from 6 to about 14 or 18 ring carbon atoms, with benzyl being an exemplary arylalkyl group; arylalkoxy, for example, having 1 to 3 separate or fused rings with benzyloxy being an exemplary arylalkoxy group; or a saturated or partially unsaturated heterocycle having 1 to 3 separate or fused rings with one or more N, O or S atoms, or a heteroaryl having 1 to 3 separate or fused rings with one or more N, O or S atoms, e.g. coumarinyl, quinolinyl, isoquinolinyl, quinazolinyl, pyridyl, pyrazinyl, pyrimidinyl, furanyl, pyrrolyl, thienyl, thiazolyl, triazinyl, oxazolyl, isoxazolyl, imidazolyl, indolyl, benzofuranyl, benzothiazolyl, tetrahydrofuranyl, tetrahydropyranyl, piperidinyl, morpholinyl, piperazinyl, and pyrrolidinyl. Such groups may be further substituted, e.g. with hydroxy, alkyl, alkoxy, halogen and amino. In some embodiments “optionally substituted” includes one or more substituents independently selected from halogen, hydroxyl, amino, cyano, —CHO, —COOH, —CONH2, alkyl including C1- C6alkyl, alkenyl including C2-C6alkenyl, alkynyl including C2-C6alkynyl, —C1-C6alkoxy, alkanoyl including C2-C6alkanoyl, C1-C6alkylester, (mono- and di-C1-C6alkylamino)C0-C2alkyl, haloalkyl including C1-C6haloalkyl, hydoxyC1-C6alkyl, ester, carbamate, urea, sulfonamide, —C1- C6alkyl(heterocyclo), C1-C6alkyl(heteroaryl), —C1-C6alkyl(C3-C7cycloalkyl), O—C1-C6alkyl(C3- C7cycloalkyl), B(OH)2, phosphate, phosphonate and haloalkoxy including C1-C6haloalkoxy. When the term “substituted” appears prior or after a list of possible substituted groups, it is intended that the term apply to every member of that group. For example, the phrase “substituted alkyl and aryl” is to be interpreted as “substituted alkyl and substituted aryl.” Attorney Ref: 92VF-350823-WO Client Ref: 021WO In addition to the disclosure herein, the term “substituted,” when used to modify a specified group or radical, can also mean that one or more hydrogen atoms of the specified group or radical are each, independently of one another, replaced with the same or different substituent groups as defined herein. In addition to the disclosure herein, in a certain embodiment, a group that is substituted has 1, 2, 3, or 4 substituents, 1, 2, or 3 substituents, 1 or 2 substituents, or 1 substituent. Unless indicated otherwise, the nomenclature of substituents that are not explicitly defined herein are arrived at by naming the terminal portion of the functionality followed by the adjacent functionality toward the point of attachment. For example, the substituent “hydroxyalkyl” refers to the group HO- (alkyl)-. As to any of the groups disclosed herein which contain one or more substituents, it is understood, of course, that such groups do not contain any substitution or substitution patterns which are sterically impractical and / or synthetically non-feasible. In addition, the subject compounds include all stereochemical isomers arising from the substitution of these compounds. In some embodiments, a substituent may contribute to optical isomerism and / or stereo isomerism of a compound. A compound of this disclosure may form a solvate with a solvent (including water). Therefore, in one non-limiting embodiment, the present disclosure includes a solvated form of the compound. The term “solvate” refers to a molecular complex of a compound (including a salt thereof) with one or more solvent molecules. Non-limiting examples of solvents are water, ethanol, isopropanol, dimethyl sulfoxide, acetone and other common organic solvents. The term “hydrate” refers to a molecular complex comprising a compound and water. Pharmaceutically acceptable solvates in accordance with the disclosure include those wherein the solvent may be isotopically substituted, e.g. D2O, d6-acetone, d6- DMSO. A solvate can be in a liquid or solid form. Salts, solvates, hydrates, and prodrug forms of a compound are of interest. All such forms are embraced by the present disclosure. Thus, the compounds described herein include salts, solvates, hydrates, prodrug and isomer forms thereof, including the pharmaceutically acceptable salts, solvates, hydrates, prodrugs and isomers thereof. In some embodiments, a compound may be a metabolized into a pharmaceutically active derivative. Unless otherwise specified, reference to an atom is meant to include isotopes of that atom. For example, reference to H is meant to include1H,2H (i.e., D) and3H (i.e., T), and reference to C is meant to include12C and all isotopes of carbon (such as13C). Attorney Ref: 92VF-350823-WO Client Ref: 021WO Definitions of other terms and concepts appear throughout the detailed description. 2. EXAMPLES The examples in this section are offered by way of illustration, and not by way of limitation. 2.1 Preparation of ASGPR ligand-linker compounds ASGPR binding compounds and conjugates are described in International Application No. PCT / US2022 / 037227, filed July 14, 2022, and the disclosure of which is herein incorporated by reference in its entirety. The following are additional illustrative schemes and examples of how the compounds described herein can be prepared and tested. Although the examples can represent only some embodiments, it should be understood that the following examples are illustrative and not limiting. All substituents, unless otherwise specified, are as previously defined. The reagents and starting materials are readily available to one of ordinary skill in the art. The specific synthetic steps for each of the routes described may be combined in different ways, or in conjunction with steps from different schemes, to prepare the compounds described herein. Example 1: Preparation of Monovalent Amine Intermediates The following section provides details for the preparation of monovalent amine intermediate compounds which can be used in the preparation of ASGPR ligand-linker example compounds. Table 7 illustrates various monovalent amines useful for the synthesis and binding experiments. Table 7: Monovalent Amine Intermediates for synthesis and binding experiments Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 7: Monovalent Amine Intermediates for synthesis and binding experiments # Structure LCMS m / z Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 7: Monovalent Amine Intermediates for synthesis and binding experiments # Structure LCMS m / z The compounds depicted in Table 7 were prepared according to the procedures outlined herein using the appropriate starting material. (i) Synthesis of N-((2R,3R,4R,5R,6R)-2-(6-aminohexyl)-4,5-dihydroxy-6- (hydroxymethyl)tetrahydro-2H-pyran-3-yl)acetamide (XB45) 54i-1BrHO a - - - ethynyltetrahydro-2H-pyran-3-yl)acetamide (intermediate 4, 2.0 g, 1.0 eq., 4.0 mmol), piperidine (0.852 g, 2.5 eq., 10.0 mmol), copper(I) bromide (0.056 g, 0.1 eq., 0.4 mmol), and hydroxylamine hydrochloride (0.055 g, 0.2 eq., 0.4 mmol) in methanol (8.0 mL) under nitrogen atmosphere at room temperature, was added a degassed solution of 4-bromobut-3-yn-1-ol (54i-1, 0.656 g, 1.1 eq., 2.2 mmol) in methanol (2 Attorney Ref: 92VF-350823-WO Client Ref: 021WO mL) over a period of 1.5 hrs. The mixture was stirred for 2 h. After completion (monitored by LCMS & TLC), solvent was removed under reduced pressure to get crude residue which was dissolved again in ethyl acetate and washed with ice cold water. The organic layer was dried over anhydrous sodium sulfate, filtered and concentrated to give crude product which was purified by silica gel flash column chromatography using 0-50% ethyl acetate in hexane to afford N-((2R,3S,4R,5R,6R)-4,5-bis(benzyloxy)- 6-((benzyloxy)methyl)-2-(6-hydroxyhexa-1,3-diyn-1-yl)tetrahydro-2H-pyran-3-yl)acetamide (54i-2) as an off white solid. Yield: 1.9 g, 83.0%. LCMS m / z 568.13 [M+H]+. To a stirred solution of N-((2R,3S,4R,5R,6R)-4,5-bis(benzyloxy)-6-((benzyloxy)methyl)-2-(6- hydroxyhexa-1,3-diyn-1-yl)tetrahydro-2H-pyran-3-yl)acetamide (54i-2, 0.80 g, 1.0 eq., 1.41 mmol) in dichloromethane (10 mL), pyridine (0.341 mL, 3.0 eq., 4.23 mmol), 4-dimethylaminopyridine (0.08 g, 0.3 eq., 0.50 mmol) and 4-methylbenzene-1-sulfonyl chloride (0.80 g, 3.0 eq., 4.23 mmol) were added sequentially at 0 °C. Then reaction mixture was stirred for 16h at room temperature. After completion (monitored by TLC), the reaction mixture was poured into cold 1N HCl, and extracted with dichloromethane. The organic part was then washed with saturated bicarbonate followed by brine, and dried over anhydrous sodium sulfate, filtered, and concentrated to give crude residue which was purified by silica gel flash column chromatography using 0-30% ethyl acetate in hexane to afford 6- ((2R,3S,4R,5R,6R)-3-acetamido-4,5-bis(benzyloxy)-6-((benzyloxy)methyl)tetrahydro-2H-pyran-2- yl)hexa-3,5-diyn-1-yl 4-methylbenzenesulfonate (54i-3) as white solid. Yield: 0.81 g, 80.0%; LCMS, m / z 722.06 [M+H]+. A solution of 6-((2R,3S,4R,5R,6R)-3-acetamido-4,5-bis(benzyloxy)-6- ((benzyloxy)methyl)tetrahydro-2H-pyran-2-yl)hexa-3,5-diyn-1-yl 4-methylbenzenesulfonate (54i-3, 0.715 g, 1 eq., 0.990 mmol) in N, N-dimethylformamide (5 mL) was treated with sodium azide (0.322 mg, 5 eq., 4.95 mmol). The suspension was then heated at 80°C for 6h. After completion (monitored by TLC), the reaction mixture was allowed to come to room temperature, and poured into water, and extracted with ethyl acetate. The organic part was dried over anhydrous sodium sulfate, filtered, and concentrated to give crude which was purified by silica gel flash column chromatography using 0-30% ethyl acetate in hexane to afford N-((2R,3S,4R,5R,6R)-2-(6-azidohexa-1,3-diyn-1-yl)-4,5-bis(benzyloxy)- 6-((benzyloxy)methyl)tetrahydro-2H-pyran-3-yl)acetamide (54i-4) as an off white solid. Yield: 0.330 g, 56.0%; LCMS m / z 593.20 [M+H]+. To a stirred solution of N-((2R,3S,4R,5R,6R)-2-(6-azidohexa-1,3-diyn-1-yl)-4,5-bis(benzyloxy)- 6-((benzyloxy)methyl)tetrahydro-2H-pyran-3-yl)acetamide (54i-4, 1.0 eq.,0.2 g, 0.337 mmol) in a mixture of methanol (5 mL), tetrahydrofuran (2 mL), acetic acid (0.20 mL) and water (0.20 mL) was added 10% palladium on carbon (0.30 g) and the reaction mixture was stirred at room temperature under Attorney Ref: 92VF-350823-WO Client Ref: 021WO H2gas balloon pressure. After completion of reaction, the reaction mixture was filtered through celite bed and rinsed with methanol. The filtrate was concentrated under vacuum and purified by prep HPLC (30% acetonitrile in water with 0.1 % TFA) to afford N-((2R,3R,4R,5R,6R)-2-(6-aminohexyl)-4,5-dihydroxy-6- (hydroxymethyl)tetrahydro-2H-pyran-3-yl)acetamide (XB45) Yield: 0.051 g, 49.6%; LCMS m / z 305.15 [M+H]+.1H NMR (400 MHz, DMSO-d6with D2O exchange) δ 4.02-3.94 (m, 1H), 3.83-3.80 (m, 1H), 3.70 (s, 1H), 3.56-3.46 (m, 4H), 2.73 (t, J = 7.6 Hz, 2H), 1.82 (s, 3H), 1.52-1.47 (m, 3H), 1.31-1.12 (m, 7H). (ii) Synthesis of N-((2R,3R,4R,5R,6R)-2-((1-(2-(2-(2-(2-aminoethoxy)ethoxy)ethoxy)ethyl)-1H- 1,2,3-triazol-4-yl)methyl)-4,5-dihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-3-yl)acetamide (XB46) OH O F F mmol, 1.00 eq) and N-((2R,3R,4R,5R,6R)-4,5-dihydroxy-6-(hydroxymethyl)-2-(prop-2-yn-1- yl)tetrahydro-2H-pyran-3-yl)acetamide (XB4B) (116.1 mg, 0.477 mmol, 1.03 eq) in 2 mL dimethyl sulfoxide was added tetrakis(acetonitrile)copper(I) hexafluorophosphate(187.3 mg, 0.403 mmol, 1.1 eq) as a solid in one portion. The mixture stirred under nitrogen atmosphere at ambient temperature for approximately 30 minutes, then directly purified by preparatory HPLC, eluting with 1-30% acetonitrile in water with 0.1% trifluoroacetic acid. Fractions containing the desired product were combined and lyophilized to dryness to afford trifluoroacetic acid salt of Compound XB46, as a white foam. Yield: 217 mg (81%); LCMS m / z 462.4 [M+1]+.

[0010] Attorney Ref: 92VF-350823-WO Client Ref: 021WO (iii) Synthesis of N-((2R,3R,4R,5R,6R)-2-(5-(2-(2-aminoethoxy)ethoxy)pentyl)-4,5-dihydroxy-6- (hydroxymethyl)tetrahydro-2H-pyran-3-yl)acetamide (XB47) ONCbz O H To a mixture of benzyl N-[2-(2-prop-2-ynoxyethoxy)ethyl]carbamate (1.00 eq, 816 mg, 2.94 mmol) in acetone (29 mL) were added NBS (1.34 eq, 704 mg, 3.95 mmol) and silver nitrate (0.144 eq, 72.0 mg, 0.424 mmol). The mixture was stirred at room temperature for 1h and concentrated. The residue was diluted with EtOAC and washed with water (1x). The aqueous layer was extracted with EtOAc (2x). The combined organic layers were washed with brine, dried, concentrated, purified by column (0 - 50% EtOAc / hexane) to give 54iii-1 as clear oil (930 mg, yield: 89%). LCMS m / z 378.0 [M + Na]+. To a mixture of N-[(2R,3S,4R,5R,6R)-4,5-dibenzyloxy-6-(benzyloxymethyl)-2-ethynyl- tetrahydropyran-3-yl]acetamide (1.00 eq, 201 mg, 0.403 mmol; Intermediate 4) in MeCN (7.6 mL) and water (4.4 mL) was added benzyl N-[2-[2-(3-bromoprop-2-ynoxy)ethoxy]ethyl]carbamate (54iii-1, 1.20 eq, 172 mg, 0.484 mmol). The mixture was cooled to 0oC and piperidine (5.00 eq, 0.20 mL, 2.02 mmol) was added. The mixture was purged with N2and CuCl (0.240 eq, 9.6 mg, 0.0967 mmol) was added. The mixture was slowly warmed to room temperature and stirred at room temperature overnight. The mixture was diluted with EtOAc, washed with 10% citric acid (1x) and brine (1x), dried, concentrated, purified by column (0 -80% EtOAC / hexane) to give 54iii-2 as a white solid (232.2 mg, yield: 74%). LCMS m / z 775.2 [M + H]+. To a mixture of benzyl N-[2-[2-[5-[(2R,3S,4R,5R,6R)-3-acetamido-4,5-dibenzyloxy-6- (benzyloxymethyl)tetrahydropyran-2-yl]penta-2,4-diynoxy]ethoxy]ethyl]carbamate (54iii-2, 1.00 eq, 232 mg, 0.300 mmol) in HOAc (6 mL) were added10% Pd / C (220 mg) and 20% Pd(OH)2 / C (230 mg). The Attorney Ref: 92VF-350823-WO Client Ref: 021WO mixture was stirred at room temperature under hydrogen for 2.5h, filtered, concentrated, and purified by prep. HPLC (2 - 40% MeCN / 20 mM NH4OH aqueous solution) to give XB47 as a white solid (83.6 mg, yield: 74%). LCMS m / z 379.3 [M + H]+. (iv) Synthesis of N,N-dibenzyl-2-(2-((3-((2R,3S,4R,5R,6R)-4,5-bis(benzyloxy)-6- ((benzyloxy)methyl)-3-nitrotetrahydro-2H-pyran-2-yl)prop-2-yn-1-yl)oxy)ethoxy)ethan-1-amine (XB48) i. n-BuLi, THF, -50°CN ii. -50°COBn O potassium carbonate (2.32 eq, 21.82 g, 158 mmol) and acetonitrile (306.46 mL) was treated with benzyl bromide (2.10 eq, 17 mL, 143 mmol) then heated to 50 °C for 2h. The reaction was filtered through celite and the filtrate concentrated under vacuum. The residue was adsorbed to silica then purified by column chromatography (5-100% EtOAc in hexanes) to give N,N-dibenzyl-2-(2-prop-2- ynoxyethoxy)ethanamine as a clear oil. Yield: 18.4 g, 83%. LCMS m / z 324.22 [M+H]+. N,N-dibenzyl-2-(2-prop-2-ynoxyethoxy)ethanamine (1.43 eq, 3.70 g, 11.4 mmol) was dissolved in 10 mL toluene then concentrated to dryness and left under high vacuum. Next, (2R,3R,4R)-3,4- dibenzyloxy-2-(benzyloxymethyl)-5-nitro-3,4-dihydro-2H-pyran (1.00 eq, 3.70 g, 8.02 mmol) was dissolved in 10 mL toluene and concentrated under high vacuum. In an oven dried flask, a solution of (114-13) N,N-dibenzyl-2-(2-prop-2-ynoxyethoxy)ethanamine (1.43 eq, 3.70 g, 11.4 mmol) in anhydrous THF (31.814 mL) under nitrogen via balloon was cooled in a -50 °C (dry-ice bath - 1:1 Attorney Ref: 92VF-350823-WO Client Ref: 021WO MeOH / water) then treated with the slow addition of butyl lithium, 2.5M in hexanes (1.20 eq, 3.8 mL, 9.62 mmol) and the reaction was stirred @ -50 °C for 60 minutes. Next, a solution of (2R,3R,4R)-3,4- dibenzyloxy-2-(benzyloxymethyl)-5-nitro-3,4-dihydro-2H-pyran (1.00 eq, 3.70 g, 8.02 mmol) in dry THF (700 uL) was added dropwise over 5 minutes while maintaining -50 °C. After 60 minutes, the reaction was quenched with the addition of 7.1M aq. Ammonium chloride (32.8 eq, 37 mL, 263 mmol) (pH 9- 10) then the cold bath was removed and the slurry was warmed to room temperature. Desired product was extracted with EtOAc (100 mL, 50 mL) and the combined organic layer was dried over Na2SO4, filtered and concentrated under reduced pressure to give crude oil. The oil was adsorbed to silica gel then purified by silica gel chromatography (10% then 20% 2-MeTHF in hexanes) to give: N,N-dibenzyl-2-[2-[3- [(2R,3S,4R,5R,6R)-4,5-dibenzyloxy-6-(benzyloxymethyl)-3-nitro-tetrahydropyran-2-yl]prop-2- ynoxy]ethoxy]ethanamine (2.19 g, 2.79 mmol, 35 % yield). LCMS m / z 785.34 [M+H]+. A solution of N,N-dibenzyl-2-[2-[3-[(2R,3S,4R,5R,6R)-4,5-dibenzyloxy-6-(benzyloxymethyl)-3- nitro-tetrahydropyran-2-yl]prop-2-ynoxy]ethoxy]ethanamine (1.00 eq, 2.40 g, 3.06 mmol) in THF (182.03 mL), water (77.673 mL) and acetic acid (46.055 mL) was cooled over ice then treated with zinc dust (18.8 eq, 3.76 g, 57.5 mmol) followed by 12M HCl (44.3 eq, 11 mL, 135 mmol). After 90m, the reaction was filtered then re-cooled in an ice bath before it was treated with 5M sodium hydroxide (350 eq, 214 mL, 1070 mmol) at such a rate as to keep the internal temperature below 24 °C. Next, the layers were partitioned then the aqueous layer was washed with DCM (80mL) - LCMS-Org1(initial partition), Aq2, Org2 (DCM). The aqueous layer was washed with DCM (50mL) then the combined organic layer was washed with brine then dried over Na2SO4, filtered and concentrated under reduced pressure and left under high vacuum. The crude amine from step 3 (2.3 g) was dissolved in DCM (20 mL) before adding triethylamine (6.00 eq, 2557 uL, 18.3 mmol), 4-(Dimethylamino)pyridine (0.050 eq, 18.7 mg, 0.153 mmol) then acetic anhydride (9.80 eq, 2.8 mL, 30.0 mmol). After several hours, the reaction was quenched with water (20 mL) for several minutes. The organic layer was collected, and the aqueous layer was washed with DCM (2x10 mL). The organic layer was dried over Na2SO4, filtered and concentrated in the presence of silica gel for purification by silica gel chromatography (0%, 5%, 10%, 15% 2MeTHF in DCM) to give N- [(2R,3S,4R,5R,6R)-4,5-dibenzyloxy-6-(benzyloxymethyl)-2-[3-[2-[2- (dibenzylamino)ethoxy]ethoxy]prop-1-ynyl]tetrahydropyran-3-yl]acetamide. Yield: 1.86 g, 76%. LCMS m / z 797.5 [M+H]+. A mixture of N-[(2R,3S,4R,5R,6R)-4,5-dibenzyloxy-6-(benzyloxymethyl)-2-[3-[2-[2- (dibenzylamino)ethoxy]ethoxy]prop-1-ynyl]tetrahydropyran-3-yl]acetamide (1.00 eq, 3.45 g, 4.33 mmol), palladium hydroxide (0.500 eq, 3.04 g, 2.16 mmol) and 10% Pd / C, Evonik Noblyst (0.500 eq, Attorney Ref: 92VF-350823-WO Client Ref: 021WO 4.61 g, 2.16 mmol) in acetic acid (86.576 mL) under nitrogen was evacuated then back-filled with hydrogen gas via balloon - a process that was repeated 3 times before leaving under an atmosphere of hydrogen. After 3 hours, the reaction was filtered over a pad of celite, the filter cake was rinsed while stirring with 100 mL methanol. Solvents were removed under reduced pressure and the residue was azeotroped with toluene then left under high vacuum. The residue was purified by RPHPLC (5-30% acetonitrile in water w / 20mM NH4OH) and fractions lyophilized to give 927 mg of N,N-dibenzyl-2-(2- ((3-((2R,3S,4R,5R,6R)-4,5-bis(benzyloxy)-6-((benzyloxy)methyl)-3-nitrotetrahydro-2H-pyran-2-yl)prop- 2-yn-1-yl)oxy)ethoxy)ethan-1-amine, XB48, as a white solid (61% yield). (v) Synthesis of 3-(((2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6-(hydroxymethyl)tetrahydro- 2H-pyran-2-yl)thio)-N-(5-aminopentyl)propenamide (XB49) OOAcAcO S OSH AcO O Lawesson's reagent O TFA, H2O AcO O N - triyl triacetate (54v-1, 1.0 eq, 4.0 g, 10.3 mmol) in toluene (33.2 mL), Lawesson’s reagent (0.85 eq, 3.53 g, 8.73 mmol) was added and reaction mixture was heated at 100 °C for 1.5 h. After completion, reaction mixture was cooled, water was added, neutralized with solid sodium bicarbonate and extracted with ethyl acetate. The organic layer was dried over anhydrous sodium sulfate, filtered and concentrated to get crude Attorney Ref: 92VF-350823-WO Client Ref: 021WO which was purified by column chromatography using silica gel (100-200 mesh) and 0-20 % ethyl acetate in dichloromethane to afford (3aR,5R,6R,7R,7aR)-5-(acetoxymethyl)-2-methyl-3a,6,7,7a-tetrahydro-5H- pyrano[3,2-d]thiazole-6,7-diyl diacetate (54v-2) as a light yellow viscous liquid. Yield: 2.0 g, 56.37 %; LCMS m / z 346.10 [M+18]+. A solution of (3aR,5R,6R,7R,7aR)-5-(acetoxymethyl)-2-methyl-3a,6,7,7a-tetrahydro-5H- pyrano[3,2-d]thiazole-6,7-diyl diacetate (54v-2, 1.0 eq, 1.6 g, 4.63 mmol) in methanol (16 mL) and water (0.16 mL) was cooled at 0 °C, trifluoroacetic acid (0.16 mL) was added and reaction mixture was stirred at room temperature for 16 h. After completion, reaction mixture was concentrated, azeotroped with toluene (2-3 times) and dried to get afford (2R,3R,4R,5R,6R)-5-acetamido-2-(acetoxymethyl)-6- mercaptotetrahydro-2H-pyran-3,4-diyl diacetate (54v-3) as a light-yellow viscous liquid. Yield: 1.6 g(Crude); LCMS m / z 364.10 [M+1]+.A solution of (2R,3R,4R,5R,6R)-5-acetamido-2-(acetoxymethyl)-6-mercaptotetrahydro-2H- pyran-3,4-diyl diacetate (54v-3, 1.0 eq, 2.4 g, 6.6 mmol) in N,N-dimethylformamide (24 mL) was cooled at -78 °C, Lithium bis(trimethylsilyl)amide (LiHMDS, 1M in tetrahydrofuran) (1.0 eq, 6.6 mL, 6.6 mmol) was added and reaction mixture was stirred at the same temperature for 1 h. Then, oxetan-2-one (54v-3a, 1.3 eq, 0.617 g, 8.58 mmol) was added and reaction mixture stirred at room temperature for 16 h. After completion, reaction mixture was concentrated to get crude which was first purified by column chromatography using silica gel (100-200 mesh) and 0-10 % methanol in dichloromethane and then by prep HPLC (10-25 % acetonitrile in water with 0.1 % trifluoroacetic acid). Fractions containing the desired product were combined and lyophilized to dryness to afford 3-(((2R,3R,4R,5R,6R)-3-acetamido- 4,5-diacetoxy-6-(acetoxymethyl)tetrahydro-2H-pyran-2-yl)thio)propanoic acid (Cpd. No.54v-4) as a white solid. Yield: 0.732 g, 25.68 %; LCMS m / z 436.05 [M+1]+;1H NMR (400 MHz, DMSO-d6) δ 12.26 (bs, 1H), 8.15 (d, J = 7.2 Hz, 1H), 5.60 (d, J = 5.2 Hz, 1H), 5.34 (d, J = 2.4 Hz, 1H), 4.88 (dd, J = 12.0 Hz & 3.2 Hz, 1H), 4.45 (t, J = 6.8 Hz, 1H), 4.40-4.34 (m, 1H), 4.09-4.00 (m, 2H), 2.76-2.64 (m, 2H), 2.54 (d, J = 7.2 Hz, 2H), 2.10 (s, 3H), 2.10 (s, 3H), 1.90 (s, 3H), 1.80 (s, 3H). A solution of 3-(((2R,3R,4R,5R,6R)-3-acetamido-4,5-diacetoxy-6-(acetoxymethyl)tetrahydro- 2H-pyran-2-yl)thio)propanoic acid (1.00 eq, 100 mg, 0.230 mmol) and tert-butyl (5- aminopentyl)carbamate (1.1 eq, 51.1 mg, 0.253 mmol) and Diisopropylethylamine (DIPEA) (3.0 eq, 0.12 mL, 0.689 mmol) in DMF (1.15 mL) was cooled in an ice bath before adding HATU (1.2 eq, 105 mg, 0.276 mmol). After 45 minutes, the reaction was diluted with water (5 mL) and brine (5 mL) and the products were extracted with EtOAc (2x5 mL). The partitioned aqueous layer was washed with EtOAc (5 mL) and the combined organic layer was washed with citric acid then with sodium bicarbonate before Attorney Ref: 92VF-350823-WO Client Ref: 021WO being dried over Na2SO4and filtered. The filtrate was concentrated under reduced pressure to give crude material that was used in the next step without further purification. LCMS m / z 620.0 [M+H]+. A solution of 25% w / w sodium methoxide in methanol (6.0 eq, 0.29 mL, 1.26 mmol) in methanol (0.839 mL) was treated with (2R,3R,4R,5R,6R)-5-acetamido-2-(acetoxymethyl)-6-((3-((5-((tert- butoxycarbonyl)amino)pentyl)amino)-3-oxopropyl)thio)tetrahydro-2H-pyran-3,4-diyl diacetate (1.0 eq, 130 mg, 0.210 mmol). After 30 minutes, the reaction was cooled in an ice bath and the reaction solution was neutralized with 12M HCl (5.9 eq, 103 uL, 1.24 mmol) then diluted with DCM (7mL) and filtered. The filtrate was concentrated under reduced pressure to give 177 mg of crude material that was used in the next step without further purification. LCMS m / z 494.0 [M+1]+. A mixture of tert-butyl (5-(3-(((2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6- (hydroxymethyl)tetrahydro-2H-pyran-2-yl)thio)propanamido)pentyl)carbamate (1.0 eq, 103 mg, 0.209 mmol) and trifluoroacetic acid (40.0 eq, 595 uL, 8.35 mmol) in DCM (1.04 mL) was stirred at room temp for 2 h. The reaction was concentrated under reduced pressure then dissolved in water and ammonium hydroxide for purification by reversed-phase HPLC (3-50% acetonitrile in water with 200 mM NH4OH) to give 3-(((2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6-(hydroxymethyl)tetrahydro- 2H-pyran-2-yl)thio)-N-(5-aminopentyl)propenamide, XB49, as a white solid. Yield: 46 mg, 56 % (over 3 steps). LCMS m / z 394.2 [M+1]+. (vi) Synthesis of N-((2R,3R,4R,5R,6R)-2-((2-(2-(2-(2-aminoethoxy)ethoxy)ethoxy)ethyl)thio)-4,5- dihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-3-yl)acetamide (XB50) 54vi-1a O SH HO O O NBoc rt - - pyran-3,4-diyl diacetate (54vi-1, 1.0 eq, 0.800 g, 2.2 mmol) in N,N-dimethylformamide (8 mL) was cooled at -78 °C, Lithium bis(trimethylsilyl)amide (LiHMDS, 1M in tetrahydrofuran) (1.0 eq, 2.2 mL, 2.2 mmol) was added and reaction mixture was stirred at the same temperature for 1 h. Then, tert-butyl (2-(2- (2-(2-bromoethoxy)ethoxy)ethoxy)ethyl)carbamate (54vi-1a, 1.2 eq, 0.940 g, 2.64 mmol) was added and Attorney Ref: 92VF-350823-WO Client Ref: 021WO reaction mixture stirred at room temperature for 16 h. After completion, reaction mixture was concentrated to get crude which was purified by column chromatography using silica gel (100-200 mesh) and 0-5 % methanol in dichloromethane to afford (2R,3R,4R,5R,6R)-5-acetamido-2-(acetoxymethyl)-6- ((2,2-dimethyl-4-oxo-3,8,11,14-tetraoxa-5-azahexadecan-16-yl)thio)tetrahydro-2H-pyran-3,4-diyl diacetate (Cpd. No.54vi-1b) as a colourless semi solid. Yield: 0.600 g, 44.11 %; LCMS m / z 639.05 [M+1]+;1H NMR (400 MHz, DMSO-d6with D2O) δ 5.57 (d, J = 5.2 Hz, 1H), 5.31-5.30 (m, 1H), 4.89- 4.85 (m, 1H), 4.43 (t, J = 6.0 Hz, 1H), 4.36-4.32 (m, 1H), 4.06-3.97 (m, 2H), 3.60-3.56 (m, 1H), 3.54- 3.51 (m, 4H), 3.36 (t, J = 6.0 Hz, 2H), 3.03 (t, J = 5.6 Hz, 2H), 2.92 (s, 2H), 2.76 (s, 1H), 2.73-2.69 (m, 1H), 2.64-2.58 (m, 1H), 2.06 (s, 3H), 1.96-1.94 (m, 5H), 1.87 (s, 3H), 1.79 (s, 3H), 1.33 (s, 9H). A solution of (2R,3R,4R,5R,6R)-5-acetamido-2-(acetoxymethyl)-6-((2,2-dimethyl-4-oxo- 3,8,11,14-tetraoxa-5-azahexadecan-16-yl)thio)tetrahydro-2H-pyran-3,4-diyl diacetate (54vi-1b, 1.0 eq, 0.450 g, 0.705 mmol) in methanol (5 mL) was cooled at 0 °C, sodium methoxide (25 % solution in methanol) (2.0 eq, 0.33 mL, 1.41 mmol) was added and reaction mixture was stirred at room temperature for 3 h. After completion, reaction mixture was neutralized with Dowex 50WX8 hydrogen form (200-400 mesh) and filtered through sintered funnel (without celite). The filtrate was concentrated, washed with diethyl ether and dried to afford tert-butyl (2-(2-(2-(2-(((2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6- (hydroxymethyl)tetrahydro-2H-pyran-2-yl)thio)ethoxy)ethoxy)ethoxy)ethyl)carbamate (54vi-2) as an off white solid. Yield: 0.320 g, 88.64 %; LCMS m / z 513.10 [M+1]+. A solution of tert-butyl (2-(2-(2-(2-(((2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6- (hydroxymethyl)tetrahydro-2H-pyran-2-yl)thio)ethoxy)ethoxy)ethoxy)ethyl)carbamate (54vi-2, 1.0 eq, 0.320 g, 0.624 mmol) in dichloromethane (1.6 mL) was cooled at 0 °C, trifluoroacetic acid (1.6 mL) was added and reaction mixture was stirred at room temperature for 1 h. After completion, reaction mixture was concentrated, azeotroped with dichloromethane (2-3 times), washed with diethyl ether (2-3 times) and purified by prep HPLC (32-50 % acetonitrile in water with 0.1 % trifluoroacetic acid). Fractions containing the desired product were combined and lyophilized to dryness to afford N-((2R,3R,4R,5R,6R)- 2-((2-(2-(2-(2-aminoethoxy)ethoxy)ethoxy)ethyl)thio)-4,5-dihydroxy-6-(hydroxymethyl)tetrahydro-2H- pyran-3-yl)acetamide, XB50, as a light yellow viscous liquid. Yield: 0.220 g, 85.33 %; LCMS m / z 413.10 [M+1]+;1H NMR (400 MHz, DMSO-d6) δ 7.79-7.73 (m, 3H), 5.43 (d, J = 5.6 Hz, 1H), 4.67-4.60 (m, 3H), 4.18-4.12 (m, 1H), 3.88 (t, J = 5.6 Hz, 1H), 3.73 (bs, 1H), 3.60-3.45 (m, 15H), 2.98-2.97 (m, 2H), 2.70-2.64 (m, 1H), 2.57-2.54 (m, 1H), 1.81 (s, 3H). Attorney Ref: 92VF-350823-WO Client Ref: 021WO (vii) Synthesis of (2R,3R,4R,5S)-5-((4-(2-(2-(2-aminoethoxy)ethoxy)ethoxy)-6- (trifluoromethyl)pyrimidin-2-yl)amino)-2-(hydroxymethyl)tetrahydro-2H-pyran-3,4-diol (XB51) Cl N Cl N 54vii-1a c g, 1.0 eq, 4.61 mmol) in tetrahydrofuran (10 mL), sodium hydride (0.277 g, 1.5 eq., 6.91 mmol, 60% in oil) was added portion wise at 0°C under N2and allowed to stir at 0°C for 30 minutes. Then the resultant solution was added dropwise to a solution of 2,4-dichloro-6-(trifluoromethyl)pyrimidine (1.0 g, 1.0 eq, 4.61 mmol) in tetrahydrofuran (10 mL) under N2atmosphere at 0°C and allowed to stir for 10 minutes. After completion (monitored by TLC), the reaction was quenched by the addition of ice, extracted with ethyl acetate, washed with brine, dried over anhydrous sodium sulfate and concentrated to get crude which was passed through silica gel (silica gel 100-200 mesh, eluent: 10% ethyl acetate in hexane) to get crude product. (1.57 g, 3.65 mmol) as light yellow liquid which was further purified by SFC to get tert- butyl (2-(2-(2-((2-chloro-6-(trifluoromethyl)pyrimidin-4-yl)oxy)ethoxy)ethoxy)ethyl)carbamate (Cpd. No.54vii-1b) as colourless oil. Yield: 0.60 g, 35%; LCMS m / z 430.3 [M+1]+;1H NMR (400 MHz, DMSO-d6): δ 7.64 (s, 1H), 6.75 (t, J = 4.8 Hz, 1H), 4.56-4.54 (m, 2H), 3.78-3.76 (m, 2H), 3.58-3.56 (m, 2H), 3.51-3.48 (m, 2H), 3.38 (t, J = 6.0 Hz, 2H), 3.06-3.02 (m, 2H), 1.35 (s, 9H). SFC Purification Method: Column: AMYLOSE-1 (250*4.6)mm, 5um; Mobile Phase: CO2:0.1% IPAmine in HEXANE:IPA 50:50 (20:80); Flow Rate: 3.0 mL / min; Column Temperature: 40°C. Attorney Ref: 92VF-350823-WO Client Ref: 021WO A suspension of tert-butyl N-[2-[2-[2-[2-chloro-6-(trifluoromethyl)pyrimidin-4- yl]oxyethoxy]ethoxy]ethyl]carbamate (1.00 eq, 51.0 mg, 0.119 mmol), (2R,3R,4R,5S)-5-amino-2- (hydroxymethyl)tetrahydropyran-3,4-diol;hydrochloride (48-4, 2.00 eq, 47.4 mg, 0.237 mmol), Diisopropylethylamine (DIPEA) (4.00 eq, 0.083 mL, 0.475 mmol), in 420 uL of anhydrous acetonitrile was heated to 75C under N2in a sealed vial. The mixture was heated for 1 hr, added 1 eq of DIEA (20 uL) and heated overnight at 80C, then heated at 95oC for 24 hours. The mixture was cooled, diluted with water and formic acid, and the crude material was purified by Prep HPLC, eluting from a C18 column with a gradient of 10-100% CH3CN:water + 0.1% FA to give 51 mg of a white powder [77% yield]; LCMS: 557.1 [M+H]. A solution of tert-butyl N-[2-[2-[2-[2-[[(3S,4R,5R,6R)-4,5-dihydroxy-6- (hydroxymethyl)tetrahydropyran-3-yl]amino]-6-(trifluoromethyl)pyrimidin-4- yl]oxyethoxy]ethoxy]ethyl]carbamate (1.00 eq, 31.0 mg, 0.0557 mmol) in 6 mL DCM was cooled to 0C and 2mL of TFA was added. The solution was stirred for 1 hr at room temperature, at which time the solution was concentrated to a crude residue which was subsequently lyophilized from water to give (2R,3R,4R,5S)-5-((4-(2-(2-(2-aminoethoxy)ethoxy)ethoxy)-6-(trifluoromethyl)pyrimidin-2-yl)amino)-2- (hydroxymethyl)tetrahydro-2H-pyran-3,4-diol, XB51 TFA salt: 37.3 mg of a white solid (crude, TFA salt); LCMS 457.2 [M+1]. (viii) Synthesis of N-((2S,3R,4R,5R,6R)-2-(2-(2-(2-(2-aminoethoxy)ethoxy)ethoxy)ethoxy)-4,5- dihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-3-yl)acetamide (XB52) 54viii-1a HO O O O NBoc °Crt Attorney Ref: 92VF-350823-WO Client Ref: 021WO To a stirred solution of (2R,3R,4R)-3,4-bis(benzyloxy)-2-((benzyloxy)methyl)-5-nitro-3,4- dihydro-2H-pyran (54viii-1, 5.0 g, 1.0 eq., 10.8 mmol) and tert-butyl (2-(2-(2-(2- hydroxyethoxy)ethoxy)ethoxy)ethyl)carbamate (54viii-1a, 4.77 g, 1.5 eq., 16.3 mmol) in anhydrous toluene (40 mL) under Ar, activated molecular sieves (3 Å, 1.50 g) were added and the mixture stirred for 1h at room temperature Thereafter, t-BuOK (0.608 g, 0.5 eq., 5.42 mmol, 1M solution in THF) was added at 0°C, and stirred for 12h at room temperature. After completion (monitored by LCMS, & TLC), acetic acid (0.05 mL) was added to quench the reaction. Molecular sieves were filtered off and the filtrate was removed under reduced pressure to afford crude which was purified by silica gel flash column chromatography to (using 0-70% ethyl acetate in hexane) to afford tert-butyl (2-(2-(2-(2- (((2S,3R,4R,5R,6R)-4,5-bis(benzyloxy)-6-((benzyloxy)methyl)-3-nitrotetrahydro-2H-pyran-2- yl)oxy)ethoxy)ethoxy)ethoxy)ethyl)carbamate (54viii-2) as colorless syrup. Yield: 2.5 g, 30.0%; LCMS m / z 755.37 [M+H]+. To a solution of tert-butyl (2-(2-(2-(2-(((2S,3R,4R,5R,6R)-4,5-bis(benzyloxy)-6- ((benzyloxy)methyl)-3-nitrotetrahydro-2H-pyran-2-yl)oxy)ethoxy)ethoxy)ethoxy)ethyl)carbamate (54viii-2, 2.5 g, 3.31 mmol, 1.0 eq.) in glacial acetic acid (30 mL); zinc (2.6 g, 12.0 eq., 39.7 mmol) was added and then heated at 40°C for 3h. After completion (monitored by TLC), reaction mixture was diluted with methanol and was filtered through celite pad. The volatiles were evaporated out on high vacuum to yield crude tert-butyl (2-(2-(2-(2-(((2S,3R,4R,5R,6R)-3-amino-4,5-bis(benzyloxy)-6- ((benzyloxy)methyl)tetrahydro-2H-pyran-2-yl)oxy)ethoxy)ethoxy)ethoxy)ethyl)carbamate (54viii-3) as syrup which was used for next step without further purification. Yield: 2.5 g (crude); LCMS m / z 725.65 [M+H]+. To a solution of tert-butyl (2-(2-(2-(2-(((2S,3R,4R,5R,6R)-3-amino-4,5-bis(benzyloxy)-6- ((benzyloxy)methyl)tetrahydro-2H-pyran-2-yl)oxy)ethoxy)ethoxy)ethoxy)ethyl)carbamate (54viii-3, 2.5 g, 3.45 mmol, 1.0 eq.) in pyridine (20 mL), acetic anhydride (10 mL) was added at 0°C and stirred the reaction mixture for 16h at room temperature. After completion, the volatiles were evaporated under reduced pressure to get crude which was purified by silica gel flash column chromatography (40-60% ethyl acetate / hexane) to afford tert-butyl (2-(2-(2-(2-(((2S,3R,4R,5R,6R)-3-acetamido-4,5- bis(benzyloxy)-6-((benzyloxy)methyl)tetrahydro-2H-pyran-2- yl)oxy)ethoxy)ethoxy)ethoxy)ethyl)carbamate (Cpd. No.54viii-4) as off-white semi solid Yield: 2.5 g, 94.52%.; LCMS m / z 767.50 [M+H]+.1H NMR (400 MHz, DMSO-d6): δ 7.82 (d, J = 8.8 Hz, 1H), 7.35- 7.23 (m, 15H), 6.74 (t, J = 5.6 Hz, 1H), 5.75 (s, 1H), 4.76-4.70 (m, 3H), 4.59-4.43 (m, 4H), 4.29-4.23 (m, 1H), 4.04 (bs, 1H), 3.94 (t, J = 6.4 Hz, 1H), 3.75 (dd, J = 11.2, 2.4 Hz 1H), 3.68-3.63 (m, 1H), 3.58-3.54 (m, 4H), 3.53-3.47 (m, 9H), 3.37-3.34 (m, 2H), 3.05 (q, J = 6.0 Hz, 2H), 1.83 (s, 3H), 1.36 (s, 9H). Attorney Ref: 92VF-350823-WO Client Ref: 021WO To a solution of tert-butyl (2-(2-(2-(2-(((2S,3R,4R,5R,6R)-3-acetamido-4,5-bis(benzyloxy)-6- ((benzyloxy)methyl)tetrahydro-2H-pyran-2-yl)oxy)ethoxy)ethoxy)ethoxy)ethyl)carbamate (54viii-3, 1.0 g, 1.0 eq., 1.3 mmol) in methanol (15 mL), 10% Pd / C (1.0 g), and concentrated HCl (0.083 mL, 2.0 eq., 2.61 mmol) were added. Then reaction mixture was stirred at room temperature under H2gas balloon pressure for 48h. After completion, the reaction mixture was filtered on celite pad and washed the pad with methanol. The volatiles were evaporated in high vacuum to afford crude which was purified by prep- HPLC (25% acetonitrile in water with 0.1 % TFA) to afford N-((2S,3R,4R,5R,6R)-2-(2-(2-(2-(2- aminoethoxy)ethoxy)ethoxy)ethoxy)-4,5-dihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-3- yl)acetamide (XB52) as light brown semi solid Yield: 0.109 g., 21.09%; LCMS m / z 397.15 [M+H]+ 1H NMR (400 MHz, DMSO-d6with D2O exchange) δ 4.70 (d, J = 2.0 Hz, 1H), 4.01-3.98 (m, 1H), 3.77-3.72 (m, 2H), 3.63-3.44 (m, 16H), 2.95 (t, J = 4.8 Hz, 2H), 1.84 (s, 3H). (ix) Synthesis of N-((2R,3R,4R,5R,6R)-2-(2-(2-(2-(2-aminoethoxy)ethoxy)ethoxy)ethoxy)-4,5- dihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-3-yl)acetamide (XB53) AcOO OAcAcO NHAc NH2 0.9eq.) and (2S,3R,4R,5R,6R)-3-acetamido-6-(acetoxymethyl)tetrahydro-2H-pyran-2,4,5-triyl triacetate (54ix-1a) (486 mg, 1.24 mmol, 1.0 eq.) in 5 mL of 1,2-dicholomethane, stirring at ambient temperature under nitrogen atmosphere, was slowly added trimethylsilyl trifluoromethanesulfonate (45 mL, 0.25 mmol, 0.2 eq.). The mixture stirred at ambient temperature for approximately 5 minutes, then was heated to 60C. After 3 hrs., the mixture was cooled to ambient temperature and quenched with addition of triethylamine (70 mL, 0.51 mmol, 0.4 eq.). The reaction mixture was diluted further with 1,2- dicholomethane, evaporated onto silica, and purified by flash column chromatography column, eluting with 0-100% ethyl acetate / dichloromethane to afford Compound 54ix-2 as a clear thick syrup. Yield: 520 mg (75%); LCMS m / z 548.97 [M+H]+. Attorney Ref: 92VF-350823-WO Client Ref: 021WO To a solution of (2R,3R,4R,5R,6R)-5-acetamido-2-(acetoxymethyl)-6-(2-(2-(2-(2- azidoethoxy)ethoxy)ethoxy)ethoxy)tetrahydro-2H-pyran-3,4-diyl diacetate (54ix-2) (492 mg, 0.897 mmol) in 6 mL of methanol, stirring under nitrogen atmosphere at 0-5C, was added sodium methoxide (25% w / w in methanol) (1359 mg, 6.29 mmol, 7.0 eq) diluted in 3 mL of methanol. The reaction mixture stirred at ambient temperature for 30 minutes, at which time 8 mL of 1N aqueous hydrochloric acid was added slowly to achieve approximate final pH of 1-2. The reaction mixture was concentrated to approximately ¼ volume and purified by preparatory HPLC, eluting with 1-30% acetonitrile in water with 0.1% trifluoroacetic acid. Fractions containing the desired product were combined and lyophilized to dryness to afford Compound 54ix-3 as white solid. Yield: 244 mg (64%); LCMS m / z 423.06 [M+1]+. To a solution of (2R,3R,4R,5R,6R)-5-acetamido-2-(acetoxymethyl)-6-(2-(2-(2-(2- azidoethoxy)ethoxy)ethoxy)ethoxy)tetrahydro-2H-pyran-3,4-diyl diacetate (54ix-3) (239 mg, 0.566 mmol) in 15 mL methanol was added 10% w / w palladium on carbon (128 mg). The mixture was degassed under vacuum then stirred under hydrogen atmosphere via balloon. After approximately 15 minutes, the solution was filtered over Celite and washed with methanol. The filtrate was concentrated to residue, then co-evaporated from acetonitrile to afford XB53, as a clear oil. Yield: 243 mg (108%); LCMS m / z 397.25 [M+1]+. (x) Synthesis of 3-(((2S,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6-(hydroxymethyl)tetrahydro- 2H-pyran-2-yl)thio)-N-(5-aminopentyl)propenamide (XB54) 54x-1a OAc OAc OH OH AcO HO O Attorney Ref: 92VF-350823-WO Client Ref: 021WO OAc OAc OH OH AcO HO O O NH2 triacetate (54x-1, 1.0 eq, 5.0 g, 12.8 mmol) and methyl 3-mercaptopropanoate (54x-1a, 2.0 eq, 3.09 mL, 25.7 mmol) in dichloromethane (50 mL) was cooled at 0 °C, boron trifluoride diethyl etherate (5.0 eq, 8.28 mL, 64.2 mmol) was added dropwise and reaction mixture was heated at 40 °C for 16 h. Reaction was monitored by ELSD. After completion, reaction mixture was cooled, diluted with dichloromethane, washed with saturated aqueous sodium bicarbonate solution and water. The organic layer was dried over anhydrous sodium sulfate, filtered and concentrated to get crude which was purified by column chromatography using silica gel (100-200 mesh) and 0-5 % methanol in dichloromethane to afford (2R,3R,4R,5R,6S)-5-acetamido-2-(acetoxymethyl)-6-((3-methoxy-3-oxopropyl)thio)tetrahydro-2H- pyran-3,4-diyl diacetate (54x-2) as a colourless viscous liquid. Yield: 5.2 g, 87.39 %; LCMS m / z 450.1 [M+1]+. To a solution of (2R,3R,4R,5R,6S)-5-acetamido-2-(acetoxymethyl)-6-((3-methoxy-3- oxopropyl)thio)tetrahydro-2H-pyran-3,4-diyl diacetate (54x-2, 1.0 eq, 4.0 g, 8.9 mmol) in methanol (40 mL), sodium methoxide (25 % solution in methanol) (0.1 eq, 0.21 mL, 0.89 mmol) was added and reaction mixture was stirred at room temperature for 3 h. After completion, reaction mixture was neutralized with Dowex 50WX8 hydrogen form (200-400 mesh) and filtered through sintered funnel (without celite). The filtrate was concentrated and dried to afford methyl 3-(((2S,3R,4R,5R,6R)-3- acetamido-4,5-dihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl)thio)propanoate (54x-3) as an off white solid. Yield: 1.7 g, 59.0 %; LCMS m / z 324.0 [M+1]+. To a solution of methyl 3-(((2S,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6-(hydroxymethyl)tetrahydro- 2H-pyran-2-yl)thio)propanoate (54x-3, 1.0 eq, 2.0 g, 6.19 mmol) in tetrahydrofuran (18 mL), methanol (12 mL) and water (6 mL), lithium hydroxide monohydrate (2.0 eq, 0.519 g, 12.4 mmol) was added and reaction mixture was stirred at room temperature for 2 h. After completion, reaction mixture was concentrated, methanol was added, neutralized with Dowex 50WX8 hydrogen form (200-400 mesh) and filtered through sintered funnel (without celite). The filtrate was concentrated and dried to afford 3- (((2S,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2- yl)thio)propanoic acid (54x-4) as an off white sticky solid. Yield: 2.4 g (Crude); LCMS m / z 310.0 [M+1]+. Attorney Ref: 92VF-350823-WO Client Ref: 021WO To a solution of 3-(((2S,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6-(hydroxymethyl)tetrahydro- 2H-pyran-2-yl)thio)propanoic acid (54x-4, 1.0 eq, 1.1 g, 3.56 mmol) in pyridine (11 mL), acetic anhydride (10.0 eq, 3.36 mL, 35.6 mmol) was added and reaction mixture was stirred at room temperature for 16 h. After completion, reaction mixture was concentrated to get crude which was purified by column chromatography using silica gel (100-200 mesh) and 0-7 % methanol in dichloromethane to afford 3- (((2S,3R,4R,5R,6R)-3-acetamido-4,5-diacetoxy-6-(acetoxymethyl)tetrahydro-2H-pyran-2- yl)thio)propanoic acid (54x-5) as a colorless viscous liquid. Yield: 1.25 g, 76.74 %; LCMS m / z 436.0[M+1]+;1H NMR (400 MHz, DMSO-d6) δ 12.24 (s, 1H), 7.88 (d, J = 9.6 Hz, 1H), 5.27 (d, J = 3.2 Hz,1H), 4.95 (dd, J = 2.4, 10.8 Hz, 1H), 4.66 (d, J = 10.4 Hz, 1H), 4.10-3.96 (m, 4H), 2.85-2.79 (m, 1H), 2.74-2.69 (m, 1H), 2.58 (t, J = 7.2 Hz, 2H), 2.11(s, 3H), 2.00 (s, 3H), 1.90 (s, 3H), 1.77 (s, 3H). A solution of tert-butyl (5-aminopentyl)carbamate (1.2 eq, 166 mg, 0.821 mmol) and 3- (((2S,3R,4R,5R,6R)-3-acetamido-4,5-diacetoxy-6-(acetoxymethyl)tetrahydro-2H-pyran-2- yl)thio)propanoic acid (1.0 eq, 302 mg, 0.694 mmol) and DIPEA (3.0 eq, 0.36 mL, 2.08 mmol) in DMF (3.5 mL) was cooled in an ice bath before adding HATU (1.2 eq, 316 mg, 0.832 mmol) then removing the ice bath. After 45 minutes, the reaction was diluted with water (10 mL) and brine (10 mL) and the products were extracted with EtOAc (2x10 mL). The partitioned aqueous layer was washed with EtOAc (5 mL) and the combined organic layer was dried over Na2SO4and filtered. The filtrate was concentrated under reduced pressure to give crude material that was adsorbed to silica gel for purification by column chromatography (50-100% EtOAc in hexanes) to give (2R,3R,4R,5R,6S)-5-acetamido-2- (acetoxymethyl)-6-((3-((5-((tert-butoxycarbonyl)amino)pentyl)amino)-3-oxopropyl)thio)tetrahydro-2H- pyran-3,4-diyl diacetate. Yield: 319 mg, 74.2 %. LCMS m / z 619.95 [M+H]+. A solution of [(2R,3R,4R,5R,6S)-5-acetamido-3,4-diacetoxy-6-[3-[5-(tert- butoxycarbonylamino)pentylamino]-3-oxo-propyl]sulfanyl-tetrahydropyran-2-yl]methyl acetate (1.0 eq, 188 mg, 0.303 mmol) in methanol (1.5 mL) was treated with 25% w / w sodium methoxide in methanol (4.0 eq, 0.28 mL, 1.21 mmol). After 1 h, the reaction was cooled in an ice bath, neutralized with 4M HCl in dioxane (4.0 eq, 303 mL, 1.21 mmol) then concentrated under reduced pressure to give crude material. The residue was dissolved in 1:1 MeOH / DCM (3 mL) then treated with 4M HCl in dioxane (4.0 eq, 303 mL, 1.21 mmol). After 1h, the reaction was concentrated under reduced pressure. The residue was dissolved in concentrated NH4OH then purified by reversed-phase HPLC (3-30% acetonitrile in water + 10 mM NH4OH) then lyophilized to give 3-(((2S,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6- (hydroxymethyl)tetrahydro-2H-pyran-2-yl)thio)-N-(5-aminopentyl)propenamide (XB54). Yield: 102 mg, 85.5 %. LCMS m / z 394.2 [M+H]+. Attorney Ref: 92VF-350823-WO Client Ref: 021WO (xi) Synthesis of N-((2R,3R,4R,5R,6R)-2-(3-(2-(2-aminoethoxy)ethoxy)propoxy)-4,5-dihydroxy-6- (hydroxymethyl)tetrahydro-2H-pyran-3-yl)acetamide (XB55) 54xi-2a AcO O OAch 22.5 mmol) in dry tetrahydrofuran (70 mL) was cooled to 0° C. To this, borane tetrahydrofuran complex (1M in THF, 112.5 mL, 5.0 eq., 112.5 mmol) was added slowly, and the resulting reaction mixture was stirred at room temperature for 21h. After completion, conc. HCl was added dropwise to quench excess borane complex, and the resulting mixture was stirred for another 30 minutes. Thereafter, the reaction mixture was concentrated under reduced pressure to get crude which was purified by column chromatography using silica gel (100-200 mesh) and 2-5% methanol in dichloromethane to afford benzyl (2-(2-(3- hydroxypropoxy)ethoxy)ethyl)carbamate (54xi-2) as colourless viscous liquid. Yield: 2.8 g, 41.88%; LCMS: m / z 298.1 [M+H]+. To a stirred solution of (2S,3R,4R,5R,6R)-3-acetamido-6-(acetoxymethyl)tetrahydro-2H-pyran- 2,4,5-triyl triacetate (54xi-2a, 1.45 g, 1.0 eq., 3.72 mmol), and benzyl (2-(2-(3- hydroxypropoxy)ethoxy)ethyl)carbamate (54xi-2, 1.11 g, 1 eq., 3.72 mmol) in 1,2-dichloroethane (15 mL) at room temperature, was added trimethylsilyl trifluoromethanesulfonate (67.6 µL, 0.1 eq., 372 µmol) drop-wise and the reaction mixture was heated at 65° C for 6h. After completion, the reaction mixture was quenched with triethyl amine and concentrated under reduced pressure to get crude which was purified by column chromatography using silica gel (100-200 mesh) and 2-5% methanol in dichloromethane to afford (2R,3R,4R,5R,6R)-5-acetamido-2-(acetoxymethyl)-6-((3-oxo-1-phenyl-2,7,10- Attorney Ref: 92VF-350823-WO Client Ref: 021WO trioxa-4-azatridecan-13-yl)oxy)tetrahydro-2H-pyran-3,4-diyl diacetate (54xi-3) as colourless viscous liquid. Yield: 2.08 g, 89.13%; LCMS: m / z 627.0 [M+H]+. A solution of (2R,3R,4R,5R,6R)-5-acetamido-2-(acetoxymethyl)-6-((3-oxo-1-phenyl-2,7,10- trioxa-4-azatridecan-13-yl)oxy)tetrahydro-2H-pyran-3,4-diyl diacetate (54xi-3, 0.350 g, 0.559 mmol) in methanol (4 mL) was cooled to 0° C. To this, sodium methoxide (25% solution in methanol) (0.02 mL, 0.4 eq., 0.223 mmol) was added, and the resulting reaction mixture was stirred at room temperature for 3h. After completion, the reaction mixture was neutralized with Dowex 50WX8 hydrogen form (200-400 mesh) and filtered through sintered funnel (without celite). The filtrate was concentrated to afford benzyl (2-(2-(3-(((2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2- yl)oxy)propoxy)ethoxy)ethyl)carbamate (54xi-4) as colorless viscous liquid. Yield: 0.26 g, 93.0%;LCMS: m / z 501.1 [M+H]+.To a stirred solution of benzyl (2-(2-(3-(((2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6- (hydroxymethyl)tetrahydro-2H-pyran-2-yl)oxy)propoxy)ethoxy)ethyl)carbamate (54xi-4, 0.26 g, 0.519 mmol) in methanol (4 mL), 10% palladium on carbon (0.166 g) and conc. HCl (20 µL, 1.0 eq., 0.519 mmol) were added and the reaction mixture was stirred at room temperature under hydrogen gas balloon pressure for 2h. After completion, the reaction mixture was filtered through syringe filter and washed with methanol. The filtrate was concentrated and purified by prep-HPLC (30-50% acetonitrile in water with 0.1 % trifluoroacetic acid). Fractions containing the desired product were combined and lyophilized to dryness to afford N-((2R,3R,4R,5R,6R)-2-(3-(2-(2-aminoethoxy)ethoxy)propoxy)-4,5-dihydroxy-6- (hydroxymethyl)tetrahydro-2H-pyran-3-yl)acetamide (XB55) as a colourless semi-solid. Yield: 0.071 g, 37.3%; LCMS: m / z 367.1 [M+H]+;1H NMR (400 MHz, DMSO-d6with D2O exchange): δ 4.20 (d, J = 8.4 Hz, 1H), 3.76-3.64 (m, 3H), 3.59-3.55 (m, 4H), 3.58-3.48 (m, 4H), 3.47-3.39 (m, 4H), 3.31-3.28 (t, J = 6.0 Hz, 1H), 2.95 (t, J = 5.2 Hz, 2H), 1.86 (s, 3H), 1.66 (t, J = 6.8, 2H).

[0011] Attorney Ref: 92VF-350823-WO Client Ref: 021WO (xii) Synthesis of N-((2S,3R,4R,5R,6R)-2-(5-(2-(2-aminoethoxy)ethoxy)pentyl)-4,5-dihydroxy-6- (hydroxymethyl)tetrahydro-2H-pyran-3-yl)acetamide (XB56) was prepared by adapting the procedure of XB47. LCMS m / z: 379.4 [M + H]+. (xiii) Synthesis of (1S,2R,3R,4R,5S)-4-(4-((2-(2-(2-aminoethoxy)ethoxy)ethoxy)methyl)-1H-1,2,3- triazol-1-yl)-1-(hydroxymethyl)-6,8-dioxabicyclo[3.2.1]octane-2,3-diol TFA salt (XB57 TFA salt). O HO O N3F F To a solution of 2-(2-(2-(prop-2-yn-1-yloxy)ethoxy)ethoxy)ethan-1-amine (54xiii-1) (39.7 mg, 0.183 mmol, 1.0 eq.) and (1S,2R,3R,4R,5S)-4-azido-1-(hydroxymethyl)-6,8-dioxabicyclo[3.2.1]octane- 2,3-diol (XB39) (34.4 mg, 0.184 mmol, 1.0 eq.) in 0.4 mL of dimethyl sulfoxide was added tetrakis(acetonitrile)copper(I) hexafluorophosphate(67.4 mg, 0.181 mmol, 0.99 eq) as a solid in one portion. The mixture was stirred under nitrogen atmosphere at ambient temperature for approximately 15 min until completion. The reaction mixture was diluted with water, which formed a precipitate, then 2 drops of trifluoroacetic acid was added to clear the solution. The product was isolated from diluted mixture by preparatory HPLC, eluting with 1-20% acetonitrile in water with 0.1% trifluoroacetic acid. Fractions containing the desired product were combined and lyophilized to dryness to afford trifluoroacetic acid salt of Compound XB57 as a clear oil. Yield: 47.9 mg (50%); LCMS m / z 405.3 [M+1]+. (xiv) Synthesis of N-((2R,3R,4R,5R,6R)-2-(6-(2-(2-aminoethoxy)ethoxy)hexyl)-4,5-dihydroxy-6- (hydroxymethyl)tetrahydro-2H-pyran-3-yl)acetamide (XB58) HO O 54xiv-3 Br BocHN OO NH2 Attorney Ref: 92VF-350823-WO Client Ref: 021WO A solution (A) of N-((2R,3R,4R,5R,6R)-4,5-dihydroxy-6-(hydroxymethyl)-2-(prop-2-yn-1- yl)tetra hydro-2H-pyran-3-yl)acetamide (XB4B, 0.4 g, 1.0 eq., 1.4 mmol), piperidine (0.298 g, 2.5 eq., 3.49 mmol), copper(I) bromide (0.02 g, 0.1 eq., 0.140 mmol) and hydroxylamine hydrochloride (0.0194 g, 0.2 eq., 0.28 mmol) in methanol (8 mL) was purged with N2for 30 minutes. Another solution (B) of tert-butyl (2-(2-((3-bromoprop-2-yn-1-yl)oxy)ethoxy)ethyl)carbamate (54xiv-3, 0.45 g, 1.0 eq., 1.4 mmol) in methanol (4 mL) was purged with N2for 30 minutes. Solution (B) was added slowly to solution (A) through syringe over a period of 15 minutes, and the reaction mixture was stirred at room temperature for 12 h. After completion, methanol was removed under reduced pressure and the crude product obtained was poured into ice cold water (10 mL), and extracted with ethyl acetate. The organic layer was dried over anhydrous sodium sulphate, filtered and concentrated to afford tert-butyl (2-(2-((6- ((2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl)hexa-2,4- diyn-1-yl)oxy)ethoxy)ethyl)carbamate (54xiv-4) as colourless viscous liquid. Yield: 0.18 g (Crude); LCMS: m / z 385.2 [M+H]+. To a solution of tert-butyl (2-(2-((6-((2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6- (hydroxymethyl)tetrahydro-2H-pyran-2-yl)hexa-2,4-diyn-1-yl)oxy)ethoxy)ethyl)carbamate (54xiv-4, 0.10 g, 1.0 eq., 0.206 mmol) in methanol (3 mL), 10 % palladium on carbon (0.070 g) was added and reaction mixture was stirred under hydrogen gas atmosphere at room temperature for 3h. After completion (monitored by LCMS., reaction mixture was filtered through syringe filter, filtrate was concentrated to afford tert-butyl (2-(2-((6-((2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6-(hydroxymethyl)tetrahydro- 2H-pyran-2-yl)hexyl)oxy)ethoxy)ethyl)carbamate (54xiv-5) as a colorless viscous liquid. Yield: 0.090 g; LCMS: m / z 493.15 [M+H]+. A solution of tert-butyl (2-(2-((6-((2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6- (hydroxymethyl)tetrahydro-2H-pyran-2-yl)hexyl)oxy)ethoxy)ethyl)carbamate (54xiv-5, 1.0 eq, 0.090 g, 0.182 mmol) in dichloromethane (2 mL) was cooled at 0 °C, trifluoroacetic acid (0.4 mL) was added and reaction mixture was stirred at room temperature for 3h. After completion, reaction mixture was concentrated to get crude which was purified by prep HPLC (20-50 % acetonitrile in water with 0.1 % trifluoroacetic acid). Fractions containing the desired product were combined and lyophilized to dryness to afford N-((2R,3R,4R,5R,6R)-2-(6-(2-(2-aminoethoxy)ethoxy)hexyl)-4,5-dihydroxy-6- (hydroxymethyl)tetrahydro-2H-pyran-3-yl)acetamide (XB58) as a brown solid. Yield: 0.015 g, 20.25 %; LCMS: m / z 393.2 [M+1]+;1H NMR (400 MHz, DMSO-d6with D2O) δ 3.99-3.94 (m, 1H), 3.82-3.79 (m, 1H), 3.70 (bs, 1H), 3.51-3.49 (m, 7H), 3.37 (t, J = 6.4 Hz, 2H), 2.95 (t, J = 4.8 Hz, 2H), 1.8 (s, 3H), 1.53- 1.44 (m, 4H), 1.24-1.15 (m, 6H). Attorney Ref: 92VF-350823-WO Client Ref: 021WO Example 2: Preparation of Cys Reactive ASGPR Targeting Compounds The following section provides details for the preparation of example trivalent and divalent Cys reactive ASGPR target compounds. Table 8 illustrates various trivalent Cys reactive ASGPR target compounds synthesized using the starting amines indicated in table 14 via the general methods described below (Methods A-C). Table 8: Synthesis of trivalent Cys reactive ASGPR targeting compounds Compound #, Starting amine used, synthesis method and LCMS m / z observed Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 8: Synthesis of trivalent Cys reactive ASGPR targeting compounds Compound #, Starting amine used, synthesis method and LCMS m / z observed Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 8: Synthesis of trivalent Cys reactive ASGPR targeting compounds Compound #, Starting amine used, synthesis method and LCMS m / z observed

[0012] Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 8: Synthesis of trivalent Cys reactive ASGPR targeting compounds Compound #, Starting amine used, synthesis method and LCMS m / z observed

[0013] Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 8: Synthesis of trivalent Cys reactive ASGPR targeting compounds Compound #, Starting amine used, synthesis method and LCMS m / z observed Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 8: Synthesis of trivalent Cys reactive ASGPR targeting compounds Compound #, Starting amine used, synthesis method and LCMS m / z observed

[0014] Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 8: Synthesis of trivalent Cys reactive ASGPR targeting compounds Compound #, Starting amine used, synthesis method and LCMS m / z observed

[0015] Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 8: Synthesis of trivalent Cys reactive ASGPR targeting compounds Compound #, Starting amine used, synthesis method and LCMS m / z observed O

[0016] Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 8: Synthesis of trivalent Cys reactive ASGPR targeting compounds Compound #, Starting amine used, synthesis method and LCMS m / z observed Table 9 illustrates various divalent Cys reactive ASGPR target compounds synthesized via the general methods described herein. Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 9: Synthesis of divalent Cys reactive ASGPR targeting compounds Compound #, Starting amine used, synthesis method and LCMS m / z observed Attorney Ref: 92VF-350823-WO Client Ref: 021WO Method A (e.g., for the synthesis of Compound 1248) HOOF F HO O O HO NHAc F NH Attorney Ref: 92VF-350823-WO Client Ref: 021WO CAS: 190714-38-6 O F N F F O O 1- yl)-16-oxo-4,7,10,13-tetraoxahexadecanoate, TFA salt(Int1): To a suspension of 1-(2-piperazin-1- ylethyl)pyrrole-2,5-dione;dihydrochloride (1.00 eq, 202 mg, 0.716 mmol) in 1.5mL of DMF was added Bis-PEG4-PFP ester (1.50 eq, 673 mg, 1.07 mmol) in 1 mL DMF, the mixture was cooled to 0°C and triethylamine (3.00 eq, 0.30 mL, 2.15 mmol) was added dropwise - mixture remains cloudy, partial slurry - stirred at 0°C for 20 min and then let warm to room temp and stirred for 30 min. The mixture was cooled to 0°C, acidified with 165uL TFA (3 eq) in approx.0.50 mL water, diluted with CH3CN, filtered and purified by preparative HPLC on C18 column (30x250mm) eluting with a gradient of 15-75-100% CH3CN / water + 0.1 %TFA. Collected 343 mg of the desired product as a clear oil after lyophilization of fractions, 63% yield. HPLC: 100% by ELSD, >99% @ 254nm [ 5-99 CH3CN / water+0.1% TFA over 8 min., 0.9 mL / min, Agilent-poroshell 120, C18, 2.7 um, 50x3 mm] LCMS 652.5 [M+1], [10-100 CH3CN / water+0.1% FA over 7 min., 0.9 ml / min, Agilent, poroshell120,C18, 2.1 mmx50mm, 2.7um]; 1H NMR (400 MHz, CDCl3) δ 6.75 (s, 2H), 3.91 (m, 6H), 3.79 (t, J = 5.8 Hz, 2H), 3.71 - 3.56 (m, 14H), 3.39 (t, J = 5.6 Hz, 2H), 3.39 (brs, 4H), 2.97 (t, J = 6.1 Hz, 2H), 2.67 (br s, 2H). LCMS: 652.5 [M+H]+. Synthesis of bis(perfluorophenyl) 3,3’-((2-(((benzyloxy)carbonyl)amino)-2-((3-oxo-3- (perfluorophenoxy)propoxy)methyl)propane-1,3-diyl)bis(oxy))dipropionate (Int2): A solution of 3,3’-((2- (((benzyloxy)carbonyl)amino)-2-((2-carboxyethoxy)methyl)propane-1,3-diyl)bis(oxy))dipropionic acid (1.0 eq, 10.0 g, 21.2 mmol) in ethyl acetate (100 mL) was cooled at 0 °C, 2,3,4,5,6-pentafluorophenol Attorney Ref: 92VF-350823-WO Client Ref: 021WO (3.0 eq, 11.7 g, 63.6 mmol) and N,N’-diisopropylcarbodiimide (4.0 eq, 13.3 mL, 84.8 mmol) were added and reaction mixture was stirred at room temperature for 16 h. After completion, reaction mixture was filtered through sintered funnel (without celite) and filtrate was concentrated to a crude residue, which was purified by column chromatography using silica gel (100-200 mesh) and 0-15 % ethyl acetate in hexane to afford bis(perfluorophenyl) 3,3’-((2-(((benzyloxy)carbonyl)amino)-2-((3-oxo-3- (perfluorophenoxy)propoxy)methyl)propane-1,3-diyl)bis(oxy))dipropionate (Int2) as an off white solid. Yield: 17.0 g, 82.66 %; LCMS m / z 970.39 [M+1]+;1H NMR (400 MHz, DMSO-d6) δ 7.34-7.26 (m, 5H), 6.58 (s, 1H), 4.95 (s, 2H), 3.75 (t, J = 5.6 Hz, 6H), 3.59 (s, 6H), 2.98 (t, J = 5.6 Hz, 6H). Synthesis of Compound 1248: A solution of N-[(2R,3R,4R,5R,6R)-2-[3-[2-(2-aminoethoxy)ethoxy]propyl]-4,5-dihydroxy-6- (hydroxymethyl)tetrahydropyran-3-yl]acetamide (3.30 eq, 346 mg, 0.987 mmol) and (2,3,4,5,6- pentafluorophenyl) 3-[2-(benzyloxycarbonylamino)-3-[3-oxo-3-(2,3,4,5,6-pentafluorophenoxy)propoxy]- 2-[[3-oxo-3-(2,3,4,5,6-pentafluorophenoxy)propoxy]methyl]propoxy]propanoate (1.00 eq, 290 mg, 0.299 mmol) in DMSO (1.4955 mL) was treated with Diisopropylethylamine (DIPEA) (3.00 eq, 156 uL, 0.897 mmol). After 90 minutes, the reaction was diluted with water (500 uL), formic acid (150uL) and methanol (350uL) and the reaction was purified by RPHPLC (3-50% CAN in water w / 0.1% FA) to give benzyl N-[2-[3-[2-[2-[3-[(2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6- (hydroxymethyl)tetrahydropyran-2-yl]propoxy]ethoxy]ethylamino]-3-oxo-propoxy]-1,1-bis[[3-[2-[2-[3- [(2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6-(hydroxymethyl)tetrahydropyran-2- yl]propoxy]ethoxy]ethylamino]-3-oxo-propoxy]methyl]ethyl]carbamate as a white solid. Yield: 405 mg, 92%. LCMS m / z 1469.1 [M+H]+. A mixture of benzyl N-[2-[3-[2-[2-[3-[(2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6- (hydroxymethyl)tetrahydropyran-2-yl]propoxy]ethoxy]ethylamino]-3-oxo-propoxy]-1,1-bis[[3-[2-[2-[3- [(2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6-(hydroxymethyl)tetrahydropyran-2- yl]propoxy]ethoxy]ethylamino]-3-oxo-propoxy]methyl]ethyl]carbamate (1.00 eq, 390 mg, 0.266 mmol) and 10% Pd / C, Evonik Noblyst (0.700 eq, 396 mg, 0.186 mmol) in methanol (5.3 mL) was stirred vigorously under an atmosphere of nitrogen gas. After 1h, the reaction was filtered through celite, the filter cake was washed with methanol (50mL) and the filtrate was concentrated under reduced pressure to a syrup. The syrup (~1.8mL) was filtered (some darkness of carbon observed) then dripped into EtOAc (8 mL) but a sticky ppt was formed so the slurry was concentrated under reduced pressure to give N-[2- [2-[3-[(2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6-(hydroxymethyl)tetrahydropyran-2- yl]propoxy]ethoxy]ethyl]-3-[3-[3-[2-[2-[3-[(2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6- (hydroxymethyl)tetrahydropyran-2-yl]propoxy]ethoxy]ethylamino]-3-oxo-propoxy]-2-[[3-[2-[2-[3- Attorney Ref: 92VF-350823-WO Client Ref: 021WO [(2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6-(hydroxymethyl)tetrahydropyran-2- yl]propoxy]ethoxy]ethylamino]-3-oxo-propoxy]methyl]-2-amino-propoxy]propenamide as a white solid. The crude material was used in the next step without further purification. Yield: 326 mg, 92%. LCMS m / z 1335.1 [M+H]+. A mixture of N-[2-[2-[3-[(2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6- (hydroxymethyl)tetrahydropyran-2-yl]propoxy]ethoxy]ethyl]-3-[3-[3-[2-[2-[3-[(2R,3R,4R,5R,6R)-3- acetamido-4,5-dihydroxy-6-(hydroxymethyl)tetrahydropyran-2-yl]propoxy]ethoxy]ethylamino]-3-oxo- propoxy]-2-[[3-[2-[2-[3-[(2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6- (hydroxymethyl)tetrahydropyran-2-yl]propoxy]ethoxy]ethylamino]-3-oxo-propoxy]methyl]-2-amino- propoxy]midazolidi (1.00 eq, 250 mg, 0.187 mmol) and (2,3,4,5,6-pentafluorophenyl) 3-[2-[2-[2-[3-[4-[2- (2,5-dioxopyrrol-1-yl)ethyl]piperazin-1-yl]-3-oxo-propoxy]ethoxy]ethoxy]ethoxy]propanoate;2,2,2- trifluoroacetic acid (1.20 eq, 172 mg, 0.225 mmol) in DMF (1.8734 mL) was treated with diisopropylethylamine (4.00 eq, 131 uL, 0.749 mmol) and the reaction was stirred at room temperature. After 19h, another charge of PFP-ester was added (0.24 eq, 34 mg). After 50h, another charge of PFP-ester (0.26 eq, 40mg) was added. After 68h, the reaction was diluted with DMSO (500uL) then purified by RPHLC (2% then 10% then 10-20% acetonitrile in water w / 0.1% TFA) to give Compound 1248 as a white solid. Yield: 245mg, 68%. LCMS m / z 902.3 [M+2H]++. HPLC: 99% based on ELSD. Method B (e.g., for the synthesis of Compound 1255) FFF F Attorney Ref: 92VF-350823-WO Client Ref: 021WO OH O HO S 3- (perfluorophenoxy)propoxy)methyl)-3,6,9,12,19-pentaoxa-16-azadocosan-22-oate (Int3, 1.0 eq, 72.0 mg, 0.0649 mmol) and DIPEA (9.0 eq, 102 mL, 0.584 mmol) in DMSO (649 mL) was treated with 3- [(2S,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6-(hydroxymethyl)tetrahydropyran-2-yl]sulfanyl-N-(5- aminopentyl)midazolidi (3.3 eq, 84.3 mg, 0.214 mmol). After 2 h, the reaction was purified by reversed- phase HPLC (10-50% acetonitrile in water w / 0.1% TFA) to give (Cmpd A) N-[2-[3-[5-[3- Attorney Ref: 92VF-350823-WO Client Ref: 021WO [(2S,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6-(hydroxymethyl)tetrahydropyran-2- yl]sulfanylpropanoylamino]pentylamino]-3-oxo-propoxy]-1,1-bis[[3-[5-[3-[(2S,3R,4R,5R,6R)-3- acetamido-4,5-dihydroxy-6-(hydroxymethyl)tetrahydropyran-2-yl]sulfanylpropanoylamino]pentylamino]- 3-oxo-propoxy]methyl]ethyl]-3-[2-[2-[2-(2-azidoethoxy)ethoxy]ethoxy]ethoxy]midazolidi. Yield: 81 mg, 72%. LCMS m / z 1737.4 [M+H]+. Synthesis of Compound B: A mixture of Cmpd A (1.0 eq, 42.0 mg, 0.0242 mmol), 10% Pd / C, Evonik Noblyst (0.84 eq, 43.4 mg, 0.0204 mmol) and acetic acid (1.67 mL) was placed under a hydrogen atmosphere via balloon for 1 h. The reaction was filtered through celite then a 0.2 mm syringe filter then concentrated under reduced pressure. The residue was concentrated from water then from MeCN before leaving under high vacuum to give Cmpd B. Yield: 40 mg, 93%. LCMS m / z 1710.8 [M+H]+. Synthesis of Compound 1255: A cold solution of perfluorophenyl 4-(2,5-dioxo-2,5-dihydro-1H- pyrrol-1-yl)benzoate(1.2 eq, 5.2 mg, 0.0136 mmol) in DMA (100 mL) was added to a cold solution of Cmpd B (1.0 eq, 20.0 mg, 0.0113 mmol) and DIPEA (4.00 eq, 7.9 mL, 0.0452 mmol) in DMA (100 mL) being cooled in an ice bath. After 90 minutes, the reaction was diluted with DMSO, water and some methanol for rinsing then the crude solution was purified by reversed-phase HPLC (5-50% MeCN in water w / 0.1% formic acid) to give Compound 1255. Yield: 10 mg, 48%. LCMS m / z 1910.6 [M+H]+. Synthesis of Int3: A solution of di-tert-butyl 3,3’-((2-amino-2-((3-(tert-butoxy)-3- oxopropoxy)methyl)propane-1,3-diyl)bis(oxy))dipropionate (452 mg, 0.894 mmol, 1.00 eq.) and 2,5- dioxopyrrolidin-1-yl 1-azido-3,6,9,12-tetraoxapentadecan-15-oate (356 mg, 0.916 mmol, 1.02 eq.) in 1 mL acetonitrile was stirred under nitrogen atmosphere and heated at 45oC for 2 days until minimal starting material remained. The reaction mixture was diluted with dichloromethane and evaporated onto silica, then purified by flash column chromatography column, eluting with 0-100% ethyl acetate / dichloromethane. Fractions containing product were concentrate and dried further under high vacuum at ambient temperature to afford tert-butyl 1-azido-17,17-bis((3-(tert-butoxy)-3- oxopropoxy)methyl)-15-oxo-3,6,9,12,19-pentaoxa-16-azadocosan-22-oate as a clear thick syrup. Yield: 559 mg (78%); LCMS m / z 779.2 [M+H]+. To tert-butyl 1-azido-17,17-bis((3-(tert-butoxy)-3-oxopropoxy)methyl)-15-oxo-3,6,9,12,19- pentaoxa-16-azadocosan-22-oate (509 mg, 0.654 mmol) was added 10 mL of a pre-mixed solution of 30% trifluoroacetic acid in dichloromethane. The mixture stirred at ambient temperature for 3.5 hrs., until consumption of starting material. The solvent was evaporated to residue under a stream of nitrogen, dried further under high vacuum at ambient temperature, then dissolved in 20% water / acetonitrile and lyophilized to dryness to afford 1-azido-17,17-bis((2-carboxyethoxy)methyl)-15-oxo-3,6,9,12,19- Attorney Ref: 92VF-350823-WO Client Ref: 021WO pentaoxa-16-azadocosan-22-oic acid as a thick dark yellow color syrup. Yield: 424 mg (99%); LCMS m / z 611.3 [M+1]+, 609.4 [M-1]-. A solution of 1-azido-17,17-bis((2-carboxyethoxy)methyl)-15-oxo-3,6,9,12,19-pentaoxa-16- azadocosan-22-oic acid (81.3 mg, 0.133 mmol, 1.0 eq.) and 2,3,4,5,6-pentafluorophenol (91.8 mg, 0.499 mmol, 3.7 eq.) in 1.5 mL of dichloromethane was added N,N′-diisopropylcarbodiimide (90 mL, 0.581 mmol, 4.4 eq.). The mixture stirred at ambient temperature for 1 hr., until consumption of starting material. The reaction mixture was diluted with dichloromethane, evaporated onto silica, then purified by flash column chromatography column, eluting with 0-100% ethyl acetate / hexanes. Fractions containing product were concentrate and dried further under high vacuum at ambient temperature to afford Int3 as a clear thick syrup. Yield: 104 mg (67%); LCMS m / z 1109.1 [M+H]+. Synthesis of Int 4: F O F DIC DCM, F F O F of 2,3,4,5,6-Pentafluorophenol (1.20 eq, 300 mg, 1.63 mmol) and 4-Maleimidobenzoic acid (1.00 eq, 295 mg, 1.36 mmol) in DCM (6 mL) was added 1,3-diisopropylcarbodiimide (1.50 eq, 0.32 mL, 2.04 mmol). The mixture was stirred at room temperature for 2h and filtered. The filtrate was concentrated and purified by column (0- 25% EtOAc / hexane) to give a white solid (Int4, 449 mg, yield: 86%).1H NMR (400 MHz, CDCl3) δ 8.37 - 8.28 (m, 2H), 7.72 - 7.62 (m, 2H), 6.95 (s, 2H). Synthesis of Compound 1247: F F F F F Attorney Ref: 92VF-350823-WO Client Ref: 021WO H N OH O OH Attorney Ref: 92VF-350823-WO Client Ref: 021WO H HO N OH O OH S O OH OH 3,8,11,14-tetraoxa-5-azahexadecan-16-yl)thio)tetrahydro-2H-pyran-3,4-diyl diacetate (165 mg, 0.258 mmol) in 2 mL of methanol, stirring under nitrogen atmosphere at 0-5C, was added sodium methoxide (25% w / w in methanol) (334.8 mg, 1.55 mmol, 6.0 eq) diluted in 1.5 mL of methanol. The reaction mixture stirred at ambient temperature for 15 minutes until completion, at which time 2.0 mL of 1N aqueous hydrochloric acid was added slowly to achieve approximate final pH of 1-2. The reaction mixture was concentrated to approximately 2 mL and purified by preparatory HPLC, eluting with acetonitrile in water with 0.1% trifluoroacetic acid. Fractions containing the desired product were combined and lyophilized to dryness to afford tert-butyl (2-(2-(2-(2-(((2R,3R,4R,5R,6R)-3-acetamido- 4,5-dihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl)thio)ethoxy)ethoxy)ethoxy)ethyl)carbamate as white solid. Yield: 91.4 mg (69%); LCMS m / z 512.0 [M+1]+, 413.2 [M-Boc+1]+. To tert-butyl (2-(2-(2-(2-(((2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6- (hydroxymethyl)tetrahydro-2H-pyran-2-yl)thio)ethoxy)ethoxy)ethoxy)ethyl)carbamate (88 mg, 0.17 mmol) was added 5 mL of a pre-mixed solution of 30% trifluoroacetic acid in dichloromethane. The mixture stirred at ambient temperature for approximately 40 minutes, then solvent was evaporated to residue under a stream of nitrogen. The crude residue was diluted with a 1:1 mixture of water and dimethyl sulfoxide and purified by preparatory HPLC, eluting with 1-20% acetonitrile in water with 0.1% trifluoroacetic acid. Fractions containing the desired product were combined and lyophilized to dryness to afford the trifluoroacetic acid salt of Compound 3 as a clear oil. Yield: 60.3 mg (66%); LCMS m / z 413.3 [M+1]+. Attorney Ref: 92VF-350823-WO Client Ref: 021WO To a solution of N-((2R,3R,4R,5R,6R)-2-((2-(2-(2-(2-aminoethoxy)ethoxy)ethoxy)ethyl)thio)- 4,5-dihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-3-yl)acetamide trifluoroacetic acid (3) (37.6 mg, 0.0714 mmol, 3.3 eq.) and perfluorophenyl 1-azido-15-oxo-17,17-bis((3-oxo-3- (perfluorophenoxy)propoxy)methyl)-3,6,9,12,19-pentaoxa-16-azadocosan-22-oate (3a) (23.7 mg, 0.0214 mmol, 1.0 eq.) in 0.5 mL of dimethyl sulfoxide was added triethylamine (20 mL, 0.15 mmol, 6.7 eq.). The mixture stirred under nitrogen atmosphere at ambient temperature for 1 hour, at which time the reaction was diluted further with dimethyl sulfoxide and purified by preparatory HPLC, eluting with acetonitrile in water with 0.1% trifluoroacetic acid. Fractions containing the desired product were combined and lyophilized to dryness to afford Compound 4 as a clear residue. Yield: 22.7 mg (59%); LCMS m / z 1794.5 [M+1]+, 1791.7 [M-1]-. To a solution of (4) (20.8 mg, 0.0116 mmol) in 3 mL of methanol was added 10% w / w palladium on carbon (14 mg). The solution was degassed under vacuum, then stirred under hydrogen atmosphere using balloon. After 20 minutes, the solution was filtered over Celite and washed with methanol. The filtrate was concentrated to residue and dried further under high vacuum at ambient temperature to afford Compound 5 as a clear film. Yield: 19.1 mg (93%); LCMS m / z 1768.0 [M+1]+. To a solution of (5) (19.0 mg, 0.0108 mmol, 1.0 eq) and perfluorophenyl 4-(2,5-dioxo-2,5-dihydro-1H- pyrrol-1-yl)benzoate (Int4) (4.7 mg, 0.012 mmol, 1.1 eq.) in 0.3 mL of dimethylacetamide, stirring at 0- 5C, was added N,N-diisopropylethylamine (8 mL, 0.045 mmol, 4.2 eq.). The mixture continued to stir at 0-5C for approximately 20 minutes until completion, then was diluted with dimethyl sulfoxide and purified by preparatory HPLC, eluting with acetonitrile in water with 0.1% trifluoroacetic acid. Fractions containing the desired product were combined and lyophilized to dryness to afford Compound 1247 as a white solid. Yield: 11.1 mg (51.7%); LCMS m / z 1967.3 [M+1]+. Method C (e.g., for the synthesis of Compound 1251)

[0017] Attorney Ref: 92VF-350823-WO Client Ref: 021WO HOOO O HO NHAcNH HO (2,3,4,5,6-pentafluorophenoxy)propoxy]-2-[[3-oxo-3-(2,3,4,5,6- pentafluorophenoxy)propoxy]methyl]propoxy]propanoate (1.00 eq, 29.0 mg, 0.0299 mmol) and N- [(2R,3R,4R,5R,6R)-2-[5-[2-(2-aminoethoxy)ethoxy]pentyl]-4,5-dihydroxy-6- (hydroxymethyl)tetrahydropyran-3-yl]acetamide;2,2,2-trifluoroacetic acid (XB47 TFA salt, 3.10 eq, 45.7 mg, 0.0927 mmol) in DMSO (0.7 mL) was added DIPEA (10.0 eq, 0.052 mL, 0.299 mmol). The mixture Attorney Ref: 92VF-350823-WO Client Ref: 021WO was stirred at room temperature for 1h and was purified by prep. HPLC (2 - 40% MeCN / water with 0.1% TFA) to give 00D as a white solid (42.2 mg, yield: 91%). LCMS m / z 1552.6 [M + H]+. To a mixture of 00D (1.00 eq, 42.2 mg, 0.0272 mmol) in MeOH (4 mL) was added 10% Pd / C (14mg). The mixture was stirred at room temperature under hydrogen for 1h, filtered, concentrated to give 00E as a white solid. (38.8 mg, yield: 100%) LCMS m / z 1418.8 [M + H]+. To a mixture of (2,3,4,5,6-pentafluorophenyl) 12-[2-(2,5-dioxopyrrol-1-yl)ethylamino]-12-oxo- dodecanoate (00C, 1.50 eq, 10.1 mg, 0.0196 mmol) in DMF (0.7 mL) were added N-[2-[2-[5- [(2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6-(hydroxymethyl)tetrahydropyran-2- yl]pentoxy]ethoxy]ethyl]-3-[3-[3-[2-[2-[5-[(2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6- (hydroxymethyl)tetrahydropyran-2-yl]pentoxy]ethoxy]ethylamino]-3-oxo-propoxy]-2-[[3-[2-[2-[5- [(2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6-(hydroxymethyl)tetrahydropyran-2- yl]pentoxy]ethoxy]ethylamino]-3-oxo-propoxy]methyl]-2-amino-propoxy]midazolidi (00E, 1.00 eq, 18.5 mg, 0.0130 mmol) and Diisopropylethylamine (DIPEA) (4.00 eq, 0.0091 mL, 0.0522 mmol). The mixture was stirred at room temperature for 5h and more DIPEA (2.5 mL) was added. The mixture was stirred at room temperature overnight. More DIEA (2 mL) was added, and the mixture was stirred at room temperature for 5h and purified by prep. HPLC (2 - 50%MeCN / water with 0.1%TFA) to give 1251 as a white solid (12.8 mg, yield: 56%). LCMS m / z 1753.7 [M + H]+. Example 3: Other trivalent ligands with Cys reactive groups The following section provides details for the preparation of other example trivalent Cys reactive ASGPR target compounds. Table 10 illustrates various trivalent Cys reactive ASGPR target compounds synthesized using the starting amines indicated in table 16 via the methods indicated or described below.

[0018] Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 10: Example Trivalent Cys Reactive ASGPR Targeting Compounds Compound number and structure Starting LCMS M Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 10: Example Trivalent Cys Reactive ASGPR Targeting Compounds Compound number and structure Starting LCMS M

[0019] Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 10: Example Trivalent Cys Reactive ASGPR Targeting Compounds Compound number and structure Starting LCMS + + Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 10: Example Trivalent Cys Reactive ASGPR Targeting Compounds Compound number and structure Starting LCMS M Indicated Methods for Table 10 follow: Attorney Ref: 92VF-350823-WO Client Ref: 021WO Method D (e.g., for the synthesis of compound 1232): AcO AcOAcO O OH Attorney Ref: 92VF-350823-WO Client Ref: 021WO HO HOHO O O (acetoxymethyl)tetrahydro-2H-pyran-2-yl)hexanoic acid, which was prepared by literature routes described in Manoharan, et al, WO 2015 / 006740A2, via chemistry analogous to example 32, intermediates 32-9 described in International Application No. PCT / US2022 / 037227, filed July 14, 2022. To a solution of (57i-1) (75 mg, 0.039 mmol) in 5 mL of methanol was added 10% w / w palladium on carbon (24 mg). The mixture was degassed under vacuum, then stirred under hydrogen atmosphere via balloon. After 2.5 hrs., the solution was filtered over Celite and washed with methanol. The filtrate was concentrated to residue and dried further under high vacuum at ambient temperature to afford free amine derivative of 57i-1 as a white residue. Yield: 65 mg (93%); LCMS m / z 1787.6 [M+1]+. To a solution of the free amine derivative of 57i-1 (36 mg, 0.020 mmol) in 1 mL of methanol, stirring under nitrogen atmosphere at 0-5C, was added sodium methoxide (25% w / w in methanol) (85.5 mg, 0.396 mmol, 19 eq) diluted in 0.2 mL of methanol. Following addition, the reaction mixture stirred at ambient temperature for 30 minutes until completion, at which time 0.4 mL of 1N aqueous hydrochloric acid was added slowly to achieve approximate final pH of 1-2. The reaction mixture was diluted further with water and purified by preparatory HPLC, eluting with 1-40% acetonitrile in water with 0.1% trifluoroacetic acid. Fractions containing the desired product were combined and lyophilized to dryness to afford Compound 57i-3 as white solid. Yield: 19.2 mg (68%); LCMS m / z 1409.75 [M+1]+. To a solution of 12-(tert-butoxy)-12-oxododecanoic acid (57i-3a) (6.8 mg, 0.024 mmol, 1.8 eq.) in 0.1 mL of dimethylformamide was added N,N-diisopropylethylamine (12 mL, 0.069 mmol, 5.1 eq.) and O-(7-azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate (9.4 mg, 0.025 mmol, 1.8 eq.). The acid activation reaction mixture stirred at ambient temperature for approximately 10 min, followed by addition of (57i-3) (19.0 mg, 0.0135 mmol, 1.0 eq.) dissolved in 0.3 mL of dimethylformamide. The reaction continued to stir at ambient temperature until completion, at which time Attorney Ref: 92VF-350823-WO Client Ref: 021WO the mixture was diluted further with dimethyl sulfoxide and purified by preparatory HPLC, eluting with acetonitrile in water with 0.1% trifluoroacetic acid. Fractions containing the desired product were combined and lyophilized to dryness to afford tert-butyl 1-((2R,3R,4R,5R,6R)-3-acetamido-4,5- dihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl)-17,17-bis((3-((3-(6-((2R,3R,4R,5R,6R)-3- acetamido-4,5-dihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl)hexanamido)propyl)amino)-3- oxopropoxy)methyl)-6,12,19-trioxo-15-oxa-7,11,18-triazatriacontan-30-oate as white solid. Yield: 13.9 mg (61%); LCMS m / z 1678.7 [M+1]+. To tert-butyl 1-((2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6-(hydroxymethyl)tetrahydro-2H- pyran-2-yl)-17,17-bis((3-((3-(6-((2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6- (hydroxymethyl)tetrahydro-2H-pyran-2-yl)hexanamido)propyl)amino)-3-oxopropoxy)methyl)-6,12,19- trioxo-15-oxa-7,11,18-triazatriacontan-30-oate (14 mg, 0.0083 mmol) was added 2 mL of a pre-mixed solution of 30% trifluoroacetic acid in dichloromethane. The mixture stirred at ambient temperature for 1 hr., then solvent was evaporated to residue under a stream of nitrogen. The crude residue was diluted with dimethyl sulfoxide and purified by preparatory HPLC, eluting with acetonitrile in water with 0.1% trifluoroacetic acid. Fractions containing the desired product were combined and lyophilized to dryness to afford Compound 1232A, as a residue. Yield: 6.38 mg (39%); LCMS m / z 1622.7 [M+1]+. To a solution of 1-((2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6-(hydroxymethyl)tetrahydro- 2H-pyran-2-yl)-17,17-bis((3-((3-(6-((2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6- (hydroxymethyl)tetrahydro-2H-pyran-2-yl)hexanamido)propyl)amino)-3-oxopropoxy)methyl)-6,12,19- trioxo-15-oxa-7,11,18-triazatriacontan-30-oic acid (1232A) (6.5 mg, 0.0040 mmol, 1.0 eq.) in 0.3 mL of dimethylformamide was added N,N-diisopropylethylamine (5 mL, 0.029 mmol, 7 eq.) and O-(7- azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluronium hexafluorophosphate (2.3 mg, 0.0060 mmol, 1.5 eq.). The acid activation reaction mixture stirred at ambient temperature for approximately 10 min, followed by addition of 2-maleimidoethylamine hydrochloride (57i-5a) (0.92 mg, 0.0052 mmol, 1.3 eq.) in one portion as a solid. The mixture stirred at ambient temperature for approximately 20 minutes until completion, then was diluted with dimethyl sulfoxide and acidified with 2 drops of trifluoroacetic acid. The product was isolated by preparatory HPLC, eluting with acetonitrile in water with 0.1% trifluoroacetic acid. Fractions containing the desired product were combined and lyophilized to dryness to afford Compound 1232, as a white solid. Yield: 3.3 mg (65%); LCMS m / z 1745.0 [M+1]+. Attorney Ref: 92VF-350823-WO Client Ref: 021WO (ii) Method E (e.g., synthesis of Compound 1234): N3OO O O HCl O [2-(2- azidoethoxy)ethoxy]ethoxy]ethylamino]-3-oxo-propyl]-4-oxo-butyl]amino]-12-oxo-dodecanoic acid (57ii-1, 1.00 eq, 12.9 mg, 0.0122 mmol) in DMSO (0.3 mL) were added Diisopropylethylamine (DIPEA) (4.00 eq, 0.0085 mL, 0.0487 mmol) and HATU (1.10 eq, 5.1 mg, 0.0134 mmol), followed by addition of 2-Maleimidoethylamine hydrochloride (1.00 eq, 2.1 mg, 0.0122 mmol). The mixture was stirred at room temperature for 30 minutes and then N-[(2S,3R,4R,5R,6R)-2-ethynyl-4,5-dihydroxy-6- (hydroxymethyl)tetrahydropyran-3-yl]acetamide (XB44A, 3.30 eq, 9.2 mg, 0.0402 mmol)was added. The mixture was purged with nitrogen and Tetrakis(acetonitrile)copper(I) hexafluorophosphate (6.00 eq, 27.5 mg, 0.0730 mmol) was added. The mixture was stirred at room temperature for 3h and purified by prep. HPLC (10- 30% MeCN / water with 0.1%TFA) to give 1234 as a white solid (5.5 mg, yield: 24%). LCMS m / z 1870.9 [M + H]+. Attorney Ref: 92VF-350823-WO Client Ref: 021WO (iii) Method F (e.g., for the synthesis of Compound 1915): O F F 57iii-1 OH Attorney Ref: 92VF-350823-WO Client Ref: 021WO To a stirred solution of bis(perfluorophenyl) 3,3’-((oxybis(ethane-2,1-diyl))bis(oxy))dipropionate (57iii-1, 3.0 eq, 1.16 g, 1.99 mmol) and 4-amino-4-(3-oxo-7,10,13-trioxa-4-azahexadec-15-yn-1-yl)- N1,N7-bis(2-(2-(2-(prop-2-yn-1-yloxy)ethoxy)ethoxy)ethyl)heptanediamide (1.0 eq, 0.5 g, 0.662 mmol) in acetonitrile (5.0 mL), N,N-diisopropylethylamine (5.0 eq, 0.578 mL g, 3.31 mmol) was added at 0 °C and reaction mixture was stirred at room temperature for 12 h. After completion (monitored by LCMS), reaction mixture was concentrated under reduced pressure to get crude was purified by prep HPLC (using 30-45% acetonitrile in H2O with 0.1% TFA) to yield perfluorophenyl 14,19-dioxo-17,17-bis(3-oxo- 7,10,13-trioxa-4-azahexadec-15-yn-1-yl)-4,7,10,22,25,28-hexaoxa-13,18-diazahentriacont-1-yn-31-oate (57iii-2) as a colorless sticky solid. Yield: 0.450 g, 58.92%; LCMS m / z 1153.35 [M+1]+. To a stirred solution of perfluorophenyl 14,19-dioxo-17,17-bis(3-oxo-7,10,13-trioxa-4- azahexadec-15-yn-1-yl)-4,7,10,22,25,28-hexaoxa-13,18-diazahentriacont-1-yn-31-oate (57iii-2, 1.0 eq., 0.028 g 0.0243 mmol) and 1-(2-aminoethyl)-1H-pyrrole-2,5-dione hydrochloride (57iii-2a, 1.5 eq., 0.0063 g 0.0364 mmol) in acetonitrile (2 mL) was added N,N-diisopropylethylamine (6.0 eq., 0.00250 mL 0.146 mmol) at 0°C and then stirred at room temperature for 1.5h After completion (monitored by LCMS), reaction mixture was concentrated under reduced pressure to get crude which was purified by prep HPLC (4555% acetonitrile in water with 0.1 % TFA). Fractions containing the desired product were combined and lyophilized to dryness to afford 4-(1-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)-4-oxo- 7,10,13-trioxa-3-azahexadecan-16-amido)-4-(3-oxo-7,10,13-trioxa-4-azahexadec-15-yn-1-yl)-N1,N7- bis(2-(2-(2-(prop-2-yn-1-yloxy)ethoxy)ethoxy)ethyl)heptanediamide (57iii-2b) as an off white solid. Yield: 0.008 g, 29.73 %; LCMS m / z 1109.25 [M+1]+;1H-NMR (400 MHz, DMSO-d6with D2O exchange): δ 6.87 (s, 2H), 4.09 (d, J = 2.0 Hz, 6H), 3.56-3.42 (m, 39H), 3.38 (t, J = 5.6 Hz, 6H), 3.25 (t, J = 2.0 Hz, 2H), 3.18-3.14 (m, 8H), 2.28 (t, J = 6.0 Hz, 2H), 2.20 (t, J = 6.4 Hz, 2H), 2.01-1.97 (m, 6H), 1.77-1.74 (m, 6H). To a vial was added 8.9 mg (0.0080 mmol) of 4-(1-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)-4- oxo-7,10,13-trioxa-3-azahexadecan-16-amido)-4-(3-oxo-7,10,13-trioxa-4-azahexadec-15-yn-1-yl)- N1,N7-bis(2-(2-(2-(prop-2-yn-1-yloxy)ethoxy)ethoxy)ethyl)heptanediamide, 6.6 mg (0.029 mmol, 3.8 eq) of (1S,2R,3R,4R,5S)-4-azido-1-(hydroxymethyl)-6,8-dioxabicyclo[3.2.1]octane-2,3-diol (XB39, prepared as in Sanhueza, J. Am. Chem. Soc.2017, 139, 3528−3536) and 0.3 mL DMSO. The mixture stirred at RT until all solids dissolved, then 14.4 mg (0.0386 mmol, 3.9 eq) of tetrakis(acetonitrile)copper(I) hexafluorophosphate was added. The vial was flushed with N2, and reaction stirred at ambient temperature. After 30 min, LCMS indicated consumption of starting tri-alkyne and formation of peak with desired mass [MH+]= 1760.7 (parent, small ionization) and [MH+]= 881.0 (parent+2 / 2). The reaction mixture was diluted with DMSO and injected onto prep-LC, eluting with MeCN / H2O (0.1% Attorney Ref: 92VF-350823-WO Client Ref: 021WO TFA). Fractions containing desired product were frozen and lyophilized to white solid: 1915, 8.1 mg (57% yield). LCMS indicated [MH+]= 1761.3 Analysis by ELSD gave 100% area purity. (iv) Method G (Synthesis of Compound 1905A): O F HO FF

[0020] Attorney Ref: 92VF-350823-WO Client Ref: 021WO OHF FFO N O ethyl)amino)- 3-oxopropyl)-10,15-dioxo-3,6-dioxa-9,14-diazahexacosan-26-oate (57iv-1) (25.2 mg, 0.023 mmol, 1.0 eq.) and (2R,3R,4R,5S)-2-(hydroxymethyl)-5-((4-(prop-2-yn-1-yloxy)-6-(trifluoromethyl)pyrimidin-2- yl)amino)tetrahydro-2H-pyran-3,4-diol trifluoroacetic acid (XB24 TFA salt) (36.3 mg, 0.0761 mmol, 3.3 eq.) in 0.5 mL of dimethyl sulfoxide was added tetrakis(acetonitrile)copper(I) hexafluorophosphate(34.5 mg, 0.0926 mmol, 4.0 eq.) in one portion as a solid. The mixture stirred under nitrogen atmosphere at ambient temperature for approximately 50 minutes until consumption of (57iv-1). The reaction mixture was diluted further with dimethyl sulfoxide and purified by preparatory HPLC, eluting with acetonitrile in water with 0.1% trifluoroacetic acid. Fractions containing the desired product were combined and lyophilized to dryness to afford Compound 57iv-2 as white solid. Yield: 35.3 mg (70%); LCMS m / z 1092.2 [M / 2+1]+. To a solution of perfluorophenyl 1-(4-(((2-(((3S,4R,5R,6R)-4,5-dihydroxy-6- (hydroxymethyl)tetrahydro-2H-pyran-3-yl)amino)-6-(trifluoromethyl)pyrimidin-4-yl)oxy)methyl)-1H- 1,2,3-triazol-1-yl)-13,13-bis(3-((2-(2-(2-(4-(((2-(((3S,4R,5R,6R)-4,5-dihydroxy-6- (hydroxymethyl)tetrahydro-2H-pyran-3-yl)amino)-6-(trifluoromethyl)pyrimidin-4-yl)oxy)methyl)-1H- 1,2,3-triazol-1-yl)ethoxy)ethoxy)ethyl)amino)-3-oxopropyl)-10,15-dioxo-3,6-dioxa-9,14-diazahexacosan- 26-oate (57iv-2) (10.2 mg, 0.0047 mmol, 1.0 eq.) and 2-maleimidoethylamine hydrochloride (57iv-2a) (1.41 mg, 0.0080 mmol, 1.7 eq.) in 0.4 mL of dimethylformamide was added triethylamine (3.5 mL, 0.025 mmol, 5.3 eq.). The mixture stirred under nitrogen atmosphere at ambient temperature for Attorney Ref: 92VF-350823-WO Client Ref: 021WO approximately 30 minutes until consumption of (57iv-2). The reaction mixture was diluted further with dimethyl sulfoxide, acidified by addition of 2 drops of trifluoroacetic acid, and purified by preparatory HPLC, eluting with acetonitrile in water with 0.1% trifluoroacetic acid. Fractions containing the desired product were combined and lyophilized to dryness to afford 1905A as white solid. Yield: 2.6 mg (25%); LCMS m / z 1070.8 [M / 2+1]+. (v) Method H (synthesis of 1922): OH O - 2H-pyran-3-yl)-1H-1,2,3-triazol-4-yl)-12-oxo-2,5,8-trioxa-11-azatetradecan-14-yl)-N1,N7-bis(2-(2-(2- ((1-((3S,4R,5R,6R)-4,5-dihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-3-yl)-1H-1,2,3-triazol-4- Attorney Ref: 92VF-350823-WO Client Ref: 021WO yl)methoxy)ethoxy)ethoxy)ethyl)heptanediamide (XB32, 0.210 g, 1.0 eq, 0.159 mmol) and perfluorophenyl 12-((2-(2,5-dioxo-2,5-dihydro-1H-pyrrol-1-yl)ethyl)amino)-12-oxododecanoate (57v-2a, 0.124 g, 1.5 eq, 0.238 mmol) in dimethyl sulfoxide (3.0 mL), N,N-diisopropylethylamine (5.0 eq, 0.138 mL, 794 mmol) was added and reaction mixture was stirred at room temperature for 16h. After completion (monitored by LCMS), reaction mixture was concentrated to afford crude which was purified by prep HPLC (35-65 % acetonitrile in water with 0.05% TFA). Fractions containing the desired compound were combined and lyophilized to afford N1-(1,29-bis(1-((3S,4R,5R,6R)-4,5-dihydroxy-6- (hydroxymethyl)tetrahydro-2H-pyran-3-yl)-1H-1,2,3-triazol-4-yl)-15-(1-(1-((3S,4R,5R,6R)-4,5- dihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-3-yl)-1H-1,2,3-triazol-4-yl)-12-oxo-2,5,8-trioxa-11- azatetradecan-14-yl)-12,18-dioxo-2,5,8,22,25,28-hexaoxa-11,19-diazanonacosan-15-yl)-N12-(2-(2,5- dioxo-2,5-dihydro-1H-pyrrol-1-yl)ethyl)dodecanediamide (1922) as white solid. Yield: 0.052 g, 19.76%. LCMS m / z 1654.80 [M-1]-;1H-NMR (400 MHz, DMSO-d6with D2O): δ 8.06 (s, 3H), 6.87 (s, 2H), 4.66- 4.62 (m, 3H), 4.49 (s, 6H), 4.00-3.93 (m, 7H), 3.63 (t, J = 11.6 Hz, 5H), 3.53-3.47 (m, 35H), 3.42 (t, J = 6.4 Hz, 3H), 3.37 (t, J = 6.0 Hz, 6H), 3.18-3.13 (m, 9H), 3.15-3.13 (m, 6H), 2.01-1.91 (m, 11H), 1.78- 1.76 (m, 6H), 1.41-1.37 (m, 5H), 1.21-1.11 (m, 14H). Table 11 illustrates various divalent Cys or Lys reactive ASGPR target compounds synthesized via the methods indicated or described herein. Table 11: Example Divalent Cys or Lys Reactive ASGPR Targeting Compounds e + Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 11: Example Divalent Cys or Lys Reactive ASGPR Targeting Compounds Compound number and structure Starting LCMS e +

[0021] Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 11: Example Divalent Cys or Lys Reactive ASGPR Targeting Compounds Compound number and structure Starting LCMS e Attorney Ref: 92VF-350823-WO Client Ref: 021WO Synthesis of Compound 1235: F F F O H O OH F F azidoethoxy)ethoxy]ethoxy]ethylamino]-1-[3-[2-[2-[2-(2-azidoethoxy)ethoxy]ethoxy]ethylamino]-3-oxo- propyl]-4-oxo-butyl]amino]-12-oxo-dodecanoate (46A, 1.00 eq, 15.6 mg, 0.0164 mmol) and N- [(2R,3R,4R,5R,6R)-4,5-dihydroxy-6-(hydroxymethyl)-2-prop-2-ynyl-tetrahydropyran-3-yl]acetamide (XB4B, 2.30 eq, 9.1 mg, 0.0376 mmol) in NMP (0.25 mL) was added Tetrakis(acetonitrile)copper(I) hexafluorophosphate (4.00 eq, 24.6 mg, 0.0654 mmol). The mixture was stirred at room temperature for 1.5h. The mixture was purified by prep. HPLC (20 - 60% MeCN / water with 0.1% TFA) to give 1235 as a white solid (12.7 mg, Yield: 54%). LCMS m / z 1440.3 [M + H]+.

[0022] Attorney Ref: 92VF-350823-WO Client Ref: 021WO Synthesis of Compound 1253A: F F NH2F F

[0023] Attorney Ref: 92VF-350823-WO Client Ref: 021WO HO OO OHO NH NH O F F (hydroxymethyl)tetrahydro-2H-pyran-2-yl)-16-(15-((2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6- (hydroxymethyl)tetrahydro-2H-pyran-2-yl)-5-oxo-2,9,12-trioxa-6-azapentadecyl)-11,21-dioxo- 4,7,14,18,25,28-hexaoxa-10,22-diazahentriacontan-16-yl)carbamate (2) A mixture of N-((2R,3R,4R,5R,6R)-2-(3-(2-(2-aminoethoxy)ethoxy)propyl)-4,5-dihydroxy-6- (hydroxymethyl)tetrahydro-2H-pyran-3-yl)acetamide (XB48, 3.24 eq, 1.72 g, 4.91 mmol) and bis(perfluorophenyl) 3,3'-((2-(((benzyloxy)carbonyl)amino)-2-((3-oxo-3- (perfluorophenoxy)propoxy)methyl)propane-1,3-diyl)bis(oxy))dipropionate (1.00 eq, 1.47 g, 1.52 mmol) was treated with diisopropylethylamine (1, 3.00 eq, 862 mL, 4.95 mmol) then dissolved in DMSO (6.89 mL) with sonication. After 90 minutes the reaction was purified by reversed-phase HPLC (5% then 15- 50% acetonitrile in water w / 0.1% FA) to give 2. Yield: 2.21 g, 91%. LCMS 1468.6 [M+H]. Synthesis of N-[2-[2-[3-[(2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6- (hydroxymethyl)tetrahydropyran-2-yl]propoxy]ethoxy]ethyl]-3-[3-[3-[2-[2-[3-[(2R,3R,4R,5R,6R)-3- Attorney Ref: 92VF-350823-WO Client Ref: 021WO acetamido-4,5-dihydroxy-6-(hydroxymethyl)tetrahydropyran-2-yl]propoxy]ethoxy]ethylamino]-3-oxo- propoxy]-2-[[3-[2-[2-[3-[(2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6- (hydroxymethyl)tetrahydropyran-2-yl]propoxy]ethoxy]ethylamino]-3-oxo-propoxy]methyl]-2-amino- propoxy]propenamide (XB68A) A solution of 2 (1.00 eq, 400 mg, 0.272 mmol) in methanol (20 mL) was purged with nitrogen then treated with 10% Pd / C (0.400 eq, 232 mg, 0.109 mmol) before being evacuated then back-filled with hydrogen via balloon. After 2h, the reaction was treated with 500 mg celite then filtered over a pad of celite. The filter cake was rinsed with methanol and the filtrate was concentrated under reduced pressure. The residue was dissolved in water with minimal DMSO then purified by reversed-phase HPLC (5-50% acetonitrile in water w / 0.2 mM NH4OH) to give XB68A. Yield: 315 mg, 86.7%. LCMS 1335.6 [M+H]. Synthesis of perfluorophenyl 33-((2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6- (hydroxymethyl)tetrahydro-2H-pyran-2-yl)-18,18-bis(15-((2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy- 6-(hydroxymethyl)tetrahydro-2H-pyran-2-yl)-5-oxo-2,9,12-trioxa-6-azapentadecyl)-16,23-dioxo- 4,7,10,13,20,27,30-heptaoxa-17,24-diazatritriacontanoate (Compound 1253A) A solution of XB68A (1.00 eq, 1.10 g, 0.824 mmol) in DMF (13.7 mL) was added to a solution of bis(perfluorophenyl) 4,7,10,13-tetraoxahexadecanedioate (3, 3.00 eq, 1.55g, 2.47 mmol) in DMF (5.6 mL) drop-wise via syringe over 16 minutes. Next, DMF (2 mL) was added to the amine flask for rinsing then this solution was added to the reaction dropwise via syringe. The reaction was stirred at room temperature overnight. After 26h, the reaction was purified directly by reversed-phase HPLC (5-15-40% acetonitrile in water w / 0.1% TFA) to give solids that were not easily manipulated. The residue was treated with acetonitrile to remove water via azeotropic distillation. The residue was then dissolved in MeOH (1 volume) then diluted with DCM (95 volumes) then concentrated under high vacuum for 18h to give Compound 1253A as a powder. Yield: 1050 mg, 71%. LCMS 1777.58 [M+H]. Table 12 illustrates various monovalent Cys or Lys reactive ASGPR target compounds synthesized via the methods indicated or described below.

[0024] Attorney Ref: 92VF-350823-WO Client Ref: 021WO Table 12: Example Monovalent Cys or Lys Reactive ASGPR Targeting Compounds Compound number and structure Starting LCMS

[0025] Attorney Ref: 92VF-350823-WO Client Ref: 021WO Synthesis of Compound 1119: O H2NOO O O OOOtBu XB47 F F added a solution of Amino-PEG6-t-butyl ester (1.30 eq, 45.7 mg, 0.112 mmol) in DMF (0.4 mL). The mixture was stirred at room temperature for 1h, then N-[(2R,3R,4R,5R,6R)-2-[5-[2-(2- aminoethoxy)ethoxy]pentyl]-4,5-dihydroxy-6-(hydroxymethyl)tetrahydropyran-3-yl]acetamide (XB47, 1.00 eq, 32.5 mg, 0.0859 mmol) was added and more DMF (0.6 mL) was added. The mixture was stirred at room temperature for 5h and purified by prep. HPLC (9 - 50% MeCN / water with 0.1%FA) to give tert- butyl 3-[2-[2-[2-[2-[2-[2-[2-[2-[5-[(2R,3R,4R,5R,6R)-3-acetamido-4,5-dihydroxy-6- (hydroxymethyl)tetrahydropyran-2- yl]pentoxy]ethoxy]ethylcarbamoylamino]ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoate as a white solid (55 mg, yield: 79%). LCMS m / z 814.3 [M + H]+. To a mixture of tert-butyl 3-[2-[2-[2-[2-[2-[2-[2-[2-[5-[(2R,3R,4R,5R,6R)-3-acetamido-4,5- dihydroxy-6-(hydroxymethyl)tetrahydropyran-2- yl]pentoxy]ethoxy]ethylcarbamoylamino]ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]propanoate (1.00 eq, 55.0 mg, 0.0676 mmol) in DCM (1 mL) was added a solution of TFA (1 mL) and water (100 uL). The mixture was stirred at rt for 30 minutes, concentrated, co-evaporated with water (2x), and lyophilized to give 14B (1121) as clear syrup (54.6 mg, yield: 107%). LCMS: 758.4 [M + H]+. To a mixture of 1121 (1.00 eq, 25.5 mg, 0.0336 mmol) in DMF (0.6 mL) at 0oC was added Bis(pentafluorophenyl) carbonate (1.00 eq, 13.3 mg, 0.0336 mmol), followed by addition of a solution of 4-Methylmorpholine (1.00 eq, 0.0037 mL, 0.0336 mmol) in DMF (30 uL). The mixture was Attorney Ref: 92VF-350823-WO Client Ref: 021WO stirred at 0oC for 30 minutes and purified by prep. HPLC (10 - 70% MeCN / water with 0.1% TFA) to give 1119 as a white solid (17.3 mg, yield: 56%). LCMS m / z 924.4 [M+H]+. Synthesis of Compound 1120: O HO OONH2N3OO O OONH2HO NHAc added a solution of 2-[2-[2-[2-[2-(2-azidoethoxy)ethoxy]ethoxy]ethoxy]ethoxy]ethanamine (1.40 eq, 20.4 mg, 0.0666 mmol) in DMF (0.3 mL). The mixture was stirred at room temperature for 2h, then N- [(2R,3R,4R,5R,6R)-2-[5-[2-(2-aminoethoxy)ethoxy]pentyl]-4,5-dihydroxy-6- (hydroxymethyl)tetrahydropyran-3-yl]acetamide (05C, XB47 , 1.00 eq, 18.0 mg, 0.0476 mmol) was added. The mixture was stirred at room temperature for 5h and was purified by prep. HPLC (9 - 50% MeCN / water with 0.1% TFA) to give 05D as a white solid (26.8 mg, yield: 79%). LCMS m / z 711.3 [M + H]+. To a mixture of N-[(2R,3R,4R,5R,6R)-2-[5-[2-[2-[2-[2-[2-[2-[2-(2- azidoethoxy)ethoxy]ethoxy]ethoxy]ethoxy]ethylcarbamoylamino]ethoxy]ethoxy]pentyl]-4,5-dihydroxy- 6-(hydroxymethyl)tetrahydropyran-3-yl]acetamide (05D, 1.00 eq, 30.6 mg, 0.0430 mmol) in MeOH (4 mL) was added 10% Pd / C (13 mg). The mixture was stirred at room temperature under hydrogen for 30 Attorney Ref: 92VF-350823-WO Client Ref: 021WO minutes, filtered, concentrated, and purified by prep. HPLC (2- 50% MeCN / 20mM NH4OH aqueous solution) to give 05E, XB70 as a white solid (14.9 mg, yield: 66%). LCMS m / z 685.4 [M + H]+. To a mixture of 2,3,4,5,6-Pentafluorophenol (1.20 eq, 300 mg, 1.63 mmol) and 4- Maleimidobenzoic acid (1.00 eq, 295 mg, 1.36 mmol) in DCM (6 mL) was added 1,3- diisopropylcarbodiimide (1.50 eq, 0.32 mL, 2.04 mmol). The mixture was stirred at room temperature for 2h and filtered. The filtrate was concentrated and purified by column (0- 25% EtOAc / hexane) to give 05F as a white solid (449 mg, yield: 86%).1H NMR (400 MHz, CDCl3) δ 8.37 - 8.28 (m, 2H), 7.72 - 7.62 (m, 2H), 6.95 (s, 2H) To a mixture of (2,3,4,5,6-pentafluorophenyl) 4-(2,5-dioxopyrrol-1-yl)benzoate (05F, 1.10 eq, 11.9 mg, 0.0312 mmol) in DMA (0.1 mL) at 0oC was added a solution of N-[(2R,3R,4R,5R,6R)-2-[5-[2- [2-[2-[2-[2-[2-[2-(2- aminoethoxy)ethoxy]ethoxy]ethoxy]ethoxy]ethylcarbamoylamino]ethoxy]ethoxy]pentyl]-4,5-dihydroxy- 6-(hydroxymethyl)tetrahydropyran-3-yl]acetamide (05E, 1.00 eq, 19.4 mg, 0.0283 mmol) in DMA (0.3 mL) dropwise. The mixture was stirred at 0oC for 10 minutes. DIPEA (1.00 eq, 0.0049 mL, 0.0283 mmol) was added. The mixture was stirred at 0oC for 20 minutes. The mixture was purified by prep. HPLC (9 - 40 % MeCN / water with 0.1%formic acid) to give 1120 as a white solid (15.5 mg, yield: 62%). LCMS: 884.3. [M + H]+. Example 4: Synthesis of 2R and 6R modification Compounds The following section provides details for the preparation of example building blocks with 2R and 6R modifications. Synthesis of compound XC28:

[0026] Attorney Ref: 92VF-350823-WO Client Ref: 021WO 48-10 1a OMOM O O To a solution of 3,3,3-trifluoropropanoic acid (1, 1.0 eq, 0.100 g, 0.781 mmol) in dichloromethane (2 mL), N-hydroxysuccinimide (1a, 1.5 eq, 0.134 g, 1.17 mmol) and N,N’- dicyclohexylcarbodiimide (2.0 eq, 0.321 mL, 1.56 mmol) were added and reaction mixture was stirred at room temperature for 16 h. After completion, reaction mixture was concentrated to get crude which was purified by column chromatography using silica gel (100-200 mesh) and 0-5 % methanol in dichloromethane to afford 2,5-dioxopyrrolidin-1-yl 3,3,3-trifluoropropanoate (2) as a colourless viscousliquid. Yield: 0.050 g, 28.57 %; LCMS m / z No ionization; 1H NMR (400 MHz, CDCl3) δ 3.54-3.47 (m,2H), 2.87 (s, 4H). To a solution of (3S,4R,5R,6R)-4,5-bis(methoxymethoxy)-6- ((methoxymethoxy)methyl)tetrahydro-2H-pyran-3-amine (48-10, 1.0 eq, 0.070 g, 0.237 mmol) in N,N- dimethylformamide (1 mL), 2,5-dioxopyrrolidin-1-yl 3,3,3-trifluoropropanoate (2, 1.5 eq, 0.080 g, 0.356 mmol) and N,N-diisopropylethylamine (3.0 eq, 0.12 mL, 0.711 mmol) were added and reaction mixture was stirred at room temperature for 16 h. After completion, water was added to reaction mixture and extracted with ethyl acetate. The organic layer was washed with water, dried over anhydrous sodium sulfate, filtered and concentrated to get crude which was purified by column chromatography using silica gel (100-200 mesh) and 0-20 % ethyl acetate in hexane to afford N-((3S,4R,5R,6R)-4,5- bis(methoxymethoxy)-6-((methoxymethoxy)methyl)tetrahydro-2H-pyran-3-yl)-3,3,3- trifluoropropanamide (3) as a light yellow viscous liquid. Yield: 0.030 g, 31.22 %; LCMS m / z 423.20 [M+18]+. Attorney Ref: 92VF-350823-WO Client Ref: 021WO To a solution of N-((3S,4R,5R,6R)-4,5-bis(methoxymethoxy)-6- ((methoxymethoxy)methyl)tetrahydro-2H-pyran-3-yl)-3,3,3-trifluoropropanamide (3, 1.0 eq, 0.035 g, 0.086 mmol) in tetrahydrofuran (0.5 mL) was cooled at 0 °C, 6N hydrochloric acid (0.5 mL) was added and reaction mixture was stirred at room temperature for 16 h. After completion, reaction mixture was concentrated to get crude which was purified by prep HPLC (25-33 % acetonitrile in water with 0.1 % trifluoroacetic acid). Fractions containing the desired product were combined and lyophilized to dryness to afford N-((3S,4R,5R,6R)-4,5-dihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-3-yl)-3,3,3- trifluoropropanamide (Cpd. No. XC28) as a cream solid. Yield: 0.008 g, 33.91 %; LCMS m / z 274.10 [M+1]+;1H NMR (400 MHz, MeOD) δ 4.18-4.12 (m, 1H), 3.98-3.93 (m, 1H), 3.86 (d, J = 3.2 Hz, 1H), 3.75-3.70 (m, 1H), 3.67-3.63 (m, 1H), 3.52-3.49 (m, 1H), 3.41-3.38 (m, 1H), 3.21-3.13 (m, 2H), 3.08 (t, J = 10.8 Hz, 1H). Synthesis of Compound XC10: 1 O O BnO O BnO O DMAP - - 2H- pyran-3-amine (1a, 1.0 eq.,0.50 g.,4.11 mmol.) and (S)-2-(methoxymethyl)oxirane (1, 1.0 eq., 0.0914 g, 1.04 mmol.) in ethanol (5.0 mL) was added N,N-Diisopropylethylamine (2.0 eq,.0.403 mL, 2.31 mmol.), and reaction mixture was refluxed for 12 h. After completion reaction (monitored by LCMS.), ethanol was evaporated under reduce pressure to get crude which was purified by column chromatography using silica gel (100-200 mesh) and 0-10 % methanol in dichloromethane to afford (S)-1-(((3S,4R,5R,6R)-4,5- bis(benzyloxy)-6-((benzyloxy)methyl)tetrahydro-2H-pyran-3-yl)amino)-3-methoxypropan-2-ol (2) as an off white solid. Yield: 0.47 g, 78.12 %; LCMS m / z 522.15 [M+1]+. To a stirred solution of (S)-1-(((3S,4R,5R,6R)-4,5-bis(benzyloxy)-6- ((benzyloxy)methyl)tetrahydro-2H-pyran-3-yl)amino)-3-methoxypropan-2-ol (2, 1.0 eq., 0.37 g., 0.709 mmol) in acetonitrile (4.0 mL), 1,1’-carbonyldiimidazole (CDI) (1.5 eq., 0.173 g., 1.06 mmol) and N,N- Attorney Ref: 92VF-350823-WO Client Ref: 021WO dimethylpyridin-4-amine (, 0.1 eq., 8.67 mg 0.070 mmol) were added and reaction mixture was stirred at room temperature for 16h. After completion (monitored by LCMS), reaction mixture was concentrated under reduce pressure to get crude which was purified by flash column chromatography on silica gel using 0-50% ethyl acetate in hexane to afford a (S)-3-((3S,4R,5R,6R)-4,5-bis(benzyloxy)-6- ((benzyloxy)methyl)tetrahydro-2H-pyran-3-yl)-5-(methoxymethyl)midazolidi-2-one (3) as a colorless liquid. Yield: 0.2 g; 51.49 %, LCMS m / z 548.0 [M+1]+. To a solution of (S)-3-((3S,4R,5R,6R)-4,5-bis(benzyloxy)-6-((benzyloxy)methyl)tetrahydro-2H- pyran-3-yl)-5-(methoxymethyl)midazolidi-2-one (3, 1.0 eq., 0.2 g, 0.365 mmol) in methanol (2.0 mL) and tetrahydrofuran (2.0 mL) was added 10% palladium on carbon (0.20 g). Thereafter, reaction mixture was stirred under hydrogen atmosphere at room temperature for 24h. After completion (monitored by LCMS), catalyst was removed by filtration on celite bed and rinsed with methanol, solvents were evaporated under reduced pressure and directly purified by prep HPLC (25-35% acetonitrile in water with 0.1% TFA) Fractions containing desired product were combined and lyophilized to dryness to afford (S)-3- ((3S,4R,5R,6R)-4,5-dihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-3-yl)-5- (methoxymethyl)midazolidi-2-one (XC10) as an off white solid. Yield: 0.070 g, 73.08 %; LCMS m / z 278.10 [M+1]+.1H NMR (400 MHz, DMSO-d6with D2O exchange) δ 4.65-4.59 (m,1H), 3.80-3.73 (m, 2H), 3.62-3.56 (m, 4H), 3.48-3.40 (m, 4H), 3.27 (s, 3H), 3.26-3.20 (m, 2H). Synthesis of Compound XC25: 3aO OBnOHO O OB O O n MeO Attorney Ref: 92VF-350823-WO Client Ref: 021WO NHBoc NH2 3,4- dihydro-2H-pyran (3, 1.0 eq., 4.5 g, 9.75 mmol) and dimethyl (S)-2-hydroxysuccinate (2.0 eq., 3.16 g, 19.5 mmol) in anhydrous toluene (30 mL) under Ar, was added activated molecular sieves (3 Å, 1.50 g) and stirred for 1h at room temperature. Then, potassium tert-butoxide (1 M solution in THF, 4.88 mmol, 4.88 mL, 0.5 eq.,) was added at 0 °C and stirred for 4h at room temperature. Thereafter, acetic acid (0.5 mL) was added to quench the reaction, and molecular sieves were filtered off. The filtrate was concentrated under reduced pressure to get residue which was purified by silica gel flash column chromatography using 10% ethyl acetate in hexane to furnish dimethyl (2S)-2-(((3R,4R,5R,6R)-4,5- bis(benzyloxy)-6-((benzyloxy)methyl)-3-nitrotetrahydro-2H-pyran-2-yl)oxy)succinate (4) as colorless oil. Yield 3.1 g, 50.98%. LCMS m / z 641.32 [M+18]+. To a stirred solution of dimethyl (2S)-2-(((3R,4R,5R,6R)-4,5-bis(benzyloxy)-6- ((benzyloxy)methyl)-3-nitrotetrahydro-2H-pyran-2-yl)oxy)succinate (4, 1.0 eq., 3.1 g, 3.48 mmol) in glacial acetic acid (15 mL), zinc (12.0 eq., 2.73g, 41.8 mmol) was added at room temperature and then refluxed for 6h. After completion (monitored by TLC), the reaction mixture was diluted with methanol and filtered over celite pad. The filtrate was evaporated to get crude dimethyl (2S)-2-(((3R,4R,5R,6R)-3- amino-4,5-bis(benzyloxy)-6-((benzyloxy)methyl)tetrahydro-2H-pyran-2-yl)oxy)succinate (5) as brown syrup. Yield: 2.0 g, crude. LCMS m / z 594.12 [M+H]+. The solution of dimethyl (2S)-2-(((4R,5R,6R)-3-amino-4,5-bis(benzyloxy)-6- ((benzyloxy)methyl)tetrahydro-2H-pyran-2-yl)oxy)succinate (5, 1.0 eq.2.0 g, 3.37 mmol) in methanol (20 mL) was refluxed for 6h. The volatile was evaporated to get crude which was purified by silica gel flash column chromatography using 60-70% ethyl acetate in hexane to furnish methyl 2- ((3S,6R,7R,8R,8aR)-7,8-bis(benzyloxy)-6-((benzyloxy)methyl)-2-oxohexahydro-1H,6H-pyrano[2,3- b][1,4]oxazin-3-yl)acetate (6) as yellow sticky solid. Yield: 0.80 g, 42.28%; LCMS m / z 560.12 [M-H] -. To a stirred solution of methyl 2-((3S,6R,7R,8R,8aR)-7,8-bis(benzyloxy)-6-((benzyloxy)methyl)- 2-oxohexahydro-1H,6H-pyrano[2,3-b][1,4]oxazin-3-yl)acetate (6, 1.0 eq., 0.78 g, 1.39 mmol) in mixture Attorney Ref: 92VF-350823-WO Client Ref: 021WO of tetrahydrofuran:methanol:water (7 mL, 4:2:1,v / v / v), lithium hydroxide monohydrate (1.1 eq., 0.064 g, 1.53 mmol) was added at 0 °C and stirred at room temperature for 3h. After completion, the reaction mixture was acidified with 1N HCl and extracted by dichloromethane (3x100 mL). Then organic part was washed with brine, dried over anhydrous sodium sulfate, filtered and concentrated to give crude 2- ((3S,6R,7R,8R,8aR)-7,8-bis(benzyloxy)-6-((benzyloxy)methyl)-2-oxohexahydro-1H,6H-pyrano[2,3- b][1,4]oxazin-3-yl)acetic acid (7) which was used for next step without further purification. Yield: 0.530 g, crude; LCMS m / z 546.12 [M-H]+. To a stirred solution 2-((3S,6R,7R,8R,8aR)-7,8-bis(benzyloxy)-6-((benzyloxy)methyl)-2- oxohexahydro-1H,6H-pyrano[2,3-b][1,4]oxazin-3-yl)acetic acid (7, 1.0 eq.0.530 g, 0.968 mmol) in dry N,N-dimethylformamide (9 mL), 1-[Bis(dimethylamino)methylene]-1H-1,2,3-triazolo[4,5-b]pyridinium 3-oxide hexafluorophosphate (HATU) (1.2 eq., 0.442 g, 1.16 mmol), N,N-diisopropylethylamine, (3.0 eq., 0.521 mL, 2.9 mmol) were added at 0 °C. Then, tert-butyl (4-aminobutyl)carbamate (1.1 eq.0.20 g, 1.16 mmol) was added, and stirred the reaction mixture at room temperature for 12 h. After completion (monitored by TLC), water was added, and extracted with dichloromethane. The organic part was washed with brine, dried over anhydrous sodium sulfate, filtered and concentrated to give crude which was purified by pre-HPLC (60% acetonitrile in water with 0.1% acetic acid) to give tert-butyl (4-(2- ((3S,6R,7R,8R,8aR)-7,8-bis(benzyloxy)-6-((benzyloxy)methyl)-2-oxohexahydro-1H,6H-pyrano[2,3- b][1,4]oxazin-3-yl)acetamido)butyl)carbamate (mixture of both isomer) which was further passed through Chiral SFC to give tert-butyl (4-(2-((3S,4aR,6R,7R,8R,8aR)-7,8-bis(benzyloxy)-6-((benzyloxy)methyl)- 2-oxohexahydro-1H,6H-pyrano[2,3-b][1,4]oxazin-3-yl)acetamido)butyl)carbamate (8α, 0.120 g, 18%) and tert-butyl (4-(2-((3S,4aS,6R,7R,8R,8aR)-7,8-bis(benzyloxy)-6-((benzyloxy)methyl)-2-oxohexahydro- 1H,6H-pyrano[2,3-b][1,4]oxazin-3-yl)acetamido)butyl)carbamate (8β, 0.015 g.3% ). (8α)1H NMR (400 MHz, DMSO-d6) δ 8.44 (d, J = 4.8 Hz, 1H), 7.88 (t, J = 4.8 Hz, 1H), 7.44 (d, J = 7.2 Hz, 2H), 7.36-7.22 (m, 13H), 6.75 (t, J = 5.6 Hz, 1H), 5.29 (d, J = 2.4 Hz, 1H), 4.79-4.70 (m, 2H), 4.65-4.62 (m, 1H), 4.60-4.57 (m, 1H), 4.51-4.41 (m, 3H), 4.01 (s, 2H), 3.81 (d, J = 10 Hz, 1H), 3.56- 3.48 (m, 3H), 3.05-2.99 (m, 2H), 2.88-2.87 (m, 2H), 2.68-2.62 (m, 1H), 2.43-2.32 (m, 1H), 1.36 (s, 13H). (8β)1H NMR (400 MHz, DMSO-d6) δ 8.31 (d, J = 4.0 Hz, 1H), 7.88 (t, J = 6.0 Hz, 1H), 7.53 (d, J = 9.2 Hz, 2H), 7.49-7.20 (m, 13H), 6.77 (s, 1H), 5.25 (brs, 1H), 4.81-4.78 (m, 1H), 4.73-4.65 (m, 2H), 4.54-4.40 (m, 4H), 4.03-3.97 (m, 3H), 3.57-3.44 (m,, 3H), 3.16-3.02 (m, 2H), 2.90 (s, 2H), 2.66-2.51 (m, 2H), 1.36 (s, 14H), 1.21 (s, 1H). Method for Chiral Separation: Column Name : Chiralpak IB-N5 (250*4.6)mm, 5um; Mobile Phase : CO2:0.1%Ipamine in IPA 60:40; Flow Rate : 3.0 mL / min Column; Temperature : 40°C. Attorney Ref: 92VF-350823-WO Client Ref: 021WO To a solution of tert-butyl (4-(2-((3S,4aS,6R,7R,8R,8aR)-7,8-bis(benzyloxy)-6- ((benzyloxy)methyl)-2-oxohexahydro-1H,6H-pyrano[2,3-b][1,4]oxazin-3-yl)acetamido)butyl)carbamate (8β, 0.500 g, 0.697 mmol, 1.0 eq.) in methanol (10 mL), 10% Pd / C (0.900 g) was added and stirred at room temperature under H2gas (balloon pressure) for 48h. After completion (monitor by LCMS), the reaction mixture was filtered on celite pad and washed with methanol. The filtrate was evaporated under reduced pressure to give crude which was again treated with a mixture trifluoroacetic acid and dichloromethane (10 ml, 1:1, v / v) and stirred for 1h at room temperature. Thereafter, the reaction mixture was purified by prep-HPLC (20-30% acetonitrile in water with 0.1% TFA) to give N-(4-aminobutyl)-2- ((3S,4aS,6R,7R,8R,8aR)-7,8-dihydroxy-6-(hydroxymethyl)-2-oxohexahydro-1H,6H-pyrano[2,3- b][1,4]oxazin-3-yl)acetamide (XC25) as colorless semi solid. Yield: 0.060 g, 35%; LCMS 348.30 [M+H]+;1H NMR (400 MHz, DMSO-d6 with D2O exchange) δ 5.17 (d, J = 2.8 Hz, 1H), 4.48-4.46 (m, 1H), 3.76 (t, J = 6.4 Hz, 1H), 3.72-3.67 (m, 2H), 3.52-3.43 (m, 2H), 3.24-3.09 (m, 2H), 3.27 (dd, J = 9.6, 2.8 Hz, 1H), 3.05 (t, J = 6.8 Hz, 1H), 2.75 (t, J = 7.2 Hz, 1H), 2.61(dd, J = 14.8, 3.2 Hz, 1H), 1.52-1.46 (m, 2H), 1.44-1.39 (m, 2H). Synthesis of XC9: BnO O 1a BnO NH2.HCl dichloromethane (50 mL), 2-bromoacetyl chloride (0.7 eq,.0.772 mL, 9.32 mmol) was added dropwise at 0°C under N2and then allowed to stir at room temperature for 12h. After completion (monitored by TLC), reaction mixture was quenched by addition of ice cold water followed by extracted with dichloromethane. Organic layer was then washed with brine, dried over anhydrous sodium sulfate and concentrated under vacuum to get 2-bromo-N-(2-methoxyethyl)acetamide (1.0 g, 5.1 mmol) as colorless liquid. Yield: 1.0 g (crude), 38.31 %;1H NMR (400 MHz, DMSO-d6): δ 8.30 (bs, 1H), 4.05 (d, J = 7.20 Hz, 1H), 3.85 (s, 1H), 3.36-3.52 (m, 2H), 3.21-3.35 (m, 5H). Attorney Ref: 92VF-350823-WO Client Ref: 021WO A solution of 2-bromo-N-(2-methoxyethyl)acetamide (2.0 eq., 0.181 g 0.923 mmol) and (3S,4R,5R,6R)-4,5-bis(benzyloxy)-6-((benzyloxy)methyl)tetrahydro-2H-pyran-3-amine hydrochloride (1.0 eq., 0.2 g 0.461 mmol) in acetonitrile (5.0 mL) was cooled at 0 °C, N,N-diisopropylethylamine (0.403 mL, 50 eq., 1.02 mmol) was added and the reaction mixture was stirred at room temperature for 16h. After completion (monitored by LCMS), reaction mixture was concentrated under vacuum to get crude product which was re-dissolved in ethyl acetate, washed with ice cold water. The organic layer was dried over anhydrous sodium sulfate, concentrated to get crude which was purified by silica gel flash column chromatography using 2-5% methanol in dichloromethane to afford 2-(((3S,4R,5R,6R)-4,5- bis(benzyloxy)-6-((benzyloxy)methyl)tetrahydro-2H-pyran-3-yl)amino)-N-(2-methoxyethyl)acetamide (3) as a green oily liquid. Yield: 0.120 g, 47.41 %; LCMS m / z 549.10 [M+1]+. A solution of 2-(((3S,4R,5R,6R)-4,5-bis(benzyloxy)-6-((benzyloxy)methyl)tetrahydro-2H-pyran- 3-yl)amino)-N-(2-methoxyethyl)acetamide (3, 1.0 eq, 0.220 g, 0.401mmol) in tetrahydrofuran (4.0 mL) was cooled at 0 °C, lithium aluminum hydride (40 eq., 0.656 mL, 1.31 mmol, 1M in THF) was added and reaction mixture was stirred at room temperature for 12 h. After completion (monitored by LCMS), reaction mixture was quenched by 15 % sodium hydroxide solution, brine solution was added, then extracted with ethyl acetate. The organic layer was dried over anhydrous sodium sulfate, filtered, and concentrated to give Crude N1-((3S,4R,5R,6R)-4,5-bis(benzyloxy)-6-((benzyloxy)methyl)tetrahydro-2H- pyran-3-yl)-N2-(2-methoxyethyl)ethane-1,2-diamine (4) as brown syrup which was used for next reaction without further purification. Yield: 0.170 g (Crude); LCMS m / z 535.10 [M+1]+. To a solution of N1-((3S,4R,5R,6R)-4,5-bis(benzyloxy)-6-((benzyloxy)methyl)tetrahydro-2H- pyran-3-yl)-N2-(2-methoxyethyl)ethane-1,2-diamine (4, 1.0 eq., 0.11 g, 0.206 mmol) in acetonitrile (2.75 mL), 1-(1H-imidazole-1-carbonyl)-1H-imidazole (0.05 g, 1.5 eq., 0.309 mmol) and N,N-dimethylpyridin- 4-amine (0.1 eq., 0.0025 g 0.0020 mmol) were added and reaction mixture was stirred at room temperature for 16h. After completion (monitored by LCMS), reaction mixture was concentrated to give crude residue which was purified by flash column chromatography on silica gel using 50% ethyl acetate in hexane to afford a 1-((3S,4R,5R,6R)-4,5-bis(benzyloxy)-6-((benzyloxy)methyl)tetrahydro-2H-pyran-3- yl)-3-(2-methoxyethyl)midazolidine-2-one (5) as a colorless liquid. Yield: 0.080 g, 69.36 %; LCMS m / z 561.15 [M+1]+. To a stirred solution of 1-((3S,4R,5R,6R)-4,5-bis(benzyloxy)-6-((benzyloxy)methyl)tetrahydro- 2H-pyran-3-yl)-3-(2-methoxyethyl)midazolidine-2-one (5, 1 eq, 0.047 g 0.0838 mmol) in methanol (3 mL) were added 20% Palladium hydroxide on carbon (0.05 g) and 10% palladium on carbon (0.5 g). Then reaction mixture was purged with hydrogen gas and stirred under hydrogen atmosphere. After completion, the reaction mixture was filtered through celite bed and rinsed with methanol The filtrate was Attorney Ref: 92VF-350823-WO Client Ref: 021WO concentrated under reduce pressure to afford a crude which was purified by prep HPLC (20-30% acetonitrile in water with 0.1% TFA) to afford 1-((3S,4R,5R,6R)-4,5-dihydroxy-6- (hydroxymethyl)tetrahydro-2H-pyran-3-yl)-3-(2-methoxyethyl)midazolidine-2-one (Cpd. No. XC9) as colorless semi solid. Yield: 0.003 g, 12.5 %; LCMS m / z 291.15 [M+1]+;1H NMR (400 MHz, DMSO-d6with D2O exchange): δ 3.85-3.75 (m, 1H), 3.71 (bs, 1H), 3.61-3.53 (m, 1H), 3.45 (d, J = 6.0 Hz, 1H), 3.38 (t, J = 5.6 Hz, 1H), 3.30-3.16 (m, 7H). Synthesis of XC11: O O O O O O OH NaH, MeI, OMeH2, 10% Pd / COMe epoxy[1,3]dioxolo[4,5-d]oxepin-4(5H)-yl)methanol (1.0 eq., 0.430 g., 1.67 mmol.) in tetrahydrofuran (5 mL) was add sodium hydride (1.5 eq., 0.1 g, 2.51 mmol.) at 0° C and stirred for 30 minutes, then methyl iodide (5.0 eq., 0.520 ml.,8.36 mmol) was added and the mixture was stirred at room temperature for 2 h. After completion (monitored by TLC), reaction mixture was quenched with cold water and extracted with dichloromethane (2-3 times). The organic layer was dried over anhydrous sodium sulphate, filtered, and concentrated to get crude which was purified by column chromatography using silica gel (100-200 mesh) and 0-60 % ethyl acetate in hexane to afford (3aR,4S,7S,8R,8aR)-8-azido-4-(methoxymethyl)-2,2- dimethylhexahydro-4,7-epoxy[1,3]dioxolo[4,5-d]oxepine (2) as colorless liquid. Yield: 0.30 g, 66.16%;1H NMR (400 MHz, DMSO-d6): δ 5.43 (d, J = 2.0 Hz, 1H), 4.29 (d, J = 4.8 Hz, 2H), 3.91 (d, J = 7.6 Hz, 1H), 3.77 (d, J = 10.0 Hz, 1H), 3.66 (d, J = 7.6 Hz, 1H), 3.58 (d, J = 10.0 Hz, 1H), 3.39 (t, J = 4.8 Hz, 1H), 3.32 (d, J = 6.0 Hz, 3H), 1.45 (s, 3H), 1.31 (s, 3H). To a stirred solution of (3aR,4S,7S,8R,8aR)-8-azido-4-(methoxymethyl)-2,2-dimethylhexahydro- 4,7-epoxy[1,3]dioxolo[4,5-d]oxepine (2, 1.0 eq., 0.3 g., 1.11 mmol) in methanol (5.0 mL) was added 10% palladium on carbon (0.12 g) and stirred under hydrogen atmosphere. After completion (monitored by Attorney Ref: 92VF-350823-WO Client Ref: 021WO TLC and LCMS), the reaction mixture was filtered through celite bed and rinsed with methanol. The filtrate was concentrated under vacuum to afford (3aR,4S,7S,8R,8aR)-4-(methoxymethyl)-2,2- dimethylhexahydro-4,7-epoxy[1,3]dioxolo[4,5-d]oxepin-8-amine (3) as a light yellow viscous liquid. Yield: 0.070 g, 25.81 %; LCMS m / z 246.10 [M+1]+. To a stirred solution of (3aR,4S,7S,8R,8aR)-4-(methoxymethyl)-2,2-dimethylhexahydro-4,7- epoxy[1,3]dioxolo[4,5-d]oxepin-8-amine (3, 1.0 eq., 0.070 g.,0.285 mmol) and 2-chloro-4-(prop-2-yn-1- yloxy)-6-(trifluoromethyl)pyrimidine (1.0 eq., 0.0675 g 0.285 mmol) in acetonitrile (1.0 mL) was added N,N-diisopropylethylamine (5.0 eq., 0.249 mL 1.43 mmol) at room temperature, and then heated at 70°C for 16h. After completion (monitored by LCMS), reaction mixture was concentrated to get crude. Which was purified by column chromatography using silica gel (100-200 mesh) and 0-10 % methanol in DCM to afford N-((3aR,4S,7S,8R,8aR)-4-(methoxymethyl)-2,2-dimethylhexahydro-4,7-epoxy[1,3]dioxolo[4,5- d]oxepin-8-yl)-4-(prop-2-yn-1-yloxy)-6-(trifluoromethyl)pyrimidin-2-amine (4)as a white solid. Yield: 0.070 g, 55.07%; LCMS m / z 446.05 [M+1]+. A solution of N-((3aR,4S,7S,8R,8aR)-4-(methoxymethyl)-2,2-dimethylhexahydro-4,7- epoxy[1,3]dioxolo[4,5-d]oxepin-8-yl)-4-(prop-2-yn-1-yloxy)-6-(trifluoromethyl)pyrimidin-2-amine (1.0 eq., 0.080 g, 0.180 mmol) in dichloromethane (1.0 mL) was cooled at 0 °C, trifluoroacetic acid (1.0 mL) was added and reaction mixture was stirred at room temperature for 1 h. After completion, reaction mixture was purified by prep HPLC (45-55% acetonitrile in H2O with 0.1% TFA). Fractions containing desired compound were collected and lyophilized to afford (1S,2R,3R,4R,5S)-1-(methoxymethyl)-4-((4- (prop-2-yn-1-yloxy)-6-(trifluoromethyl)pyrimidin-2-yl)amino)-6,8-dioxabicyclo[3.2.1]octane-2,3-diol (Cpd. No. XC11) as an off white solid. Yield: 0.0013 g, 1.37 %; m / z 406.0 [M+1]+. Synthesis of XC17: O O O S O O H Attorney Ref: 92VF-350823-WO Client Ref: 021WO A solution of A (1.0 eq, 80.0 mg, 0.326 mmol) in THF (0.815 mL) was cooled in an ice bath then triethylamine (2.2 eq, 100 mL, 0.718 mmol) was added followed by p-toluenesulfonyl chloride (2.0 eq, 124 mg, 0.652 mmol). The reaction was stirred at room temperature for 1 hour then 50 °C for 18 h. The crude reaction was adsorbed to celite then purified by silica gel chromatography (0-20% MeOH in DCM) to give ((3aR,4R,7S,7aR)-7-acetamido-2,2-dimethyltetrahydro-4H-[1,3]dioxolo[4,5-c]pyran-4- yl)methyl 4-methylbenzenesulfonate. Yield: 90 mg, 69%. LCMS m / z 400.1 [M+H]+. A mixture of sodium hydride (3.0 eq, 4.5 mg, 0.113 mmol) and 1H-pyrazole (3.2 eq, 8.2 mg, 0.120 mmol) under nitrogen was dissolved in DMF (0.188 mL) then ((3aR,4R,7S,7aR)-7-acetamido-2,2- dimethyltetrahydro-4H-[1,3]dioxolo[4,5-c]pyran-4-yl)methyl 4-methylbenzenesulfonate (1.00 eq, 15.0 mg, 0.0376 mmol) was added and the reaction was stirred at room temperature for 3 h then 19 h at 80 °C. The reaction was diluted with DCM (2 mL) and water (3 mL). The organic layer was washed with water (5 mL) then dried over Na2SO4, filtered, and concentrated to give N-((3aS,4R,7S,7aR)-4-((1H- pyrazol-1-yl)methyl)-2,2-dimethyltetrahydro-4H-[1,3]dioxolo[4,5-c]pyran-7-yl)acetamide as a solid. The residue was used in the next step without further purification. LCMS m / z 296.2 [M+H]+. N-((3aS,4R,7S,7aR)-4-((1H-pyrazol-1-yl)methyl)-2,2-dimethyltetrahydro-4H-[1,3]dioxolo[4,5- c]pyran-7-yl)acetamide (1.0 eq, 7.0 mg, 0.0237 mmol) was dissolved in water (150 mL) and trifluoroacetic acid (88.8 eq, 150 mL, 2.10 mmol). After 90 minutes, the reaction was concentrated under vacuum then diluted further with water and MeOH before being purified by reversed- phase HPLC (5-30% acetonitrile in water w / 0.1% FA) to give N-((3S,4R,5R,6R)-6-((1H-pyrazol-1- yl)methyl)-4,5-dihydroxytetrahydro-2H-pyran-3-yl)acetamide (XC17). Yield: 1.0 mg, 16.5%. LCMS m / z 312.1 [M+H]+. Synthesis of XC12: 2a OAcO MeOO OMeHO O O Attorney Ref: 92VF-350823-WO Client Ref: 021WO To a stirred solution of (2R,3R,4R,5S)-5-acetamido-2-(acetoxymethyl)tetrahydro-2H-pyran-3,4- diyl diacetate (example 4848-3, 1.0 eq, 2.0 g, 6.04 mmol) in methanol (20 mL), sodium methoxide 25% w / v in methanol (0.2 eq, 10.3 mL, 179 mmol) was added drop-wise at 0 °C. The reaction mixture was allowed to stir at room temperature for 2 h. After completion (monitored by ELSD), the reaction mixture was neutralized using Dowex-hydrogen form (200-400 mesh) (up to pH-7). The reaction mixture was filtered, organic was concentrated under reduced pressure to get crude. The crude was used for the next step. Yield: 1.1 g (crude). To a solution of N-((3S,4R,5R,6R)-4,5-dihydroxy-6-(hydroxymethyl)tetrahydro-2H-pyran-3- yl)acetamide (1.1 g, 1.0 eq, 5.36 mmol) in 2,2-dimethoxypropane (20 mL ) was added camphor sulphonic acid (0.125 g, 0.1 eq, 0.536 mmol) and the reaction mixture was stirred at room temperature for 3 h. After completion, the reaction mixture was quenched with triethylamine (2.26 mL, 3.0 eq, 16.1 mmol) and concentrated under reduced pressure to obtain crude. The crude was purified by prep HPLC (10-25% acetonitrile in water with 0.05% ammonium acetate). Fractions containing the desired product were combined and lyophilized to dryness to afford N-((3aR,4R,7S,7aR)-4-(hydroxymethyl)-2,2- dimethyltetrahydro-4H-[1,3]dioxolo[4,5-c]pyran-7-yl)acetamide (3) as a white solid. Yield: 0.582 g, 44.27%; LCMS m / z 246.10 [M+1]+; 1H NMR (400 MHz, MeOD) δ 4.20 (d, J=0.8Hz, 1H), 4.00-3.97 (m, 2H), 3.85-3.81 (m, 1H), 3.73-3.69 (m, 3H), 3.04 (t, J=10.8 Hz, 1H), 1.95 (s, 3H), 1.48 (s, 3H), 1.32 (s, 3H). A solution of triphenylphosphine (1.5 eq, 27.3 mg, 0.104 mmol) in THF (0.693 mL) was cooled in an ice bath before adding diisopropyl azodicarboxylate (1.2 eq, 16 uL, 0.0832 mmol). After 5 minutes, N-((3aR,4R,7S,7aR)-4-(hydroxymethyl)-2,2-dimethyltetrahydro-4H-[1,3]dioxolo[4,5-c]pyran-7- yl)acetamide (1.00 eq, 17.0 mg, 0.0693 mmol) was added and after another 10 minutes, 4-methoxyphenol (1.5 eq, 12.9 mg, 0.104 mmol) was added and the reaction was stirred at room temperature for 1 hour then at 50 °C for 18 h. The reaction was purified directly by reversed-phase HPLC (10-50% acetonitrile in water w / 0.1% FA) to give N-((3aR,4R,7S,7aR)-4-((4-methoxyphenoxy)methyl)-2,2-dimethyltetrahydro- 4H-[1,3]dioxolo[4,5-c]pyran-7-yl)acetamide. LCMS m / z 351.5 [M+H]+. A solution of N-((3aR,4R,7S,7aR)-4-((4-methoxyphenoxy)methyl)-2,2-dimethyltetrahydro-4H- [1,3]dioxolo[4,5-c]pyran-7-yl)acetamide in a solution of TFA / water (1:1) was stirred at room temperature for 1 hour. The reaction was purified by reversed-phase HPLC (5-50% acetonitrile in water with 0.1% FA) to give N-((3S,4R,5R,6R)-4,5-dihydroxy-6-((4-methoxyphenoxy)methyl)tetrahydro-2H-pyran-3- yl)acetamide, XC12, as a white solid. Yield: 1.1 mg, 5%. LCMS m / z 312.1 [M+H]+. Attorney Ref: 92VF-350823-WO Client Ref: 021WO Synthesis of XC15: N OH OH Cl N tetrahydro-2H-pyran-3,4- diol;hydrochloride (1.00 eq, 10.0 mg, 0.0501 mmol), 2-chloropyrimidine (3.00 eq, 17.2 mg, 0.150 mmol) and DIPEA (4.00 eq, 35 mL, 0.200 mmol) in IPA (0.251 mL) and NMP (0.251 mL) was heated to 120 °C for 18 h. The reaction was diluted with water then purified by reversed-phase HPLC (4-100% acetonitrile in water w 200 mM NH4OH) to give (2R,3R,4R,5S)-2-(hydroxymethyl)-5-(pyrimidin-2- ylamino)tetrahydro-2H-pyran-3,4-diol (XC15). Yield: 1.2 mg, 10%. LCMS m / z 242.1 [M+H]+. Synthesis of XC22 and XC23: O O O HO O NaH O O O O A solution of N-( -2,2-dimethyltetrahydro-4H- [1,3]dioxolo[4,5-c]pyran-7-yl)acetamide (1.0 eq, 30.0 mg, 0.122 mmol) and sodium hydride (2.0 eq, 9.8 mg, 0.245 mmol) in DMF (0.612 mL) was cooled in an ice bath before adding iodomethane (1.5 eq, 11 mL, 0.183 mmol) then removing the ice bath. After 1 hour, the reaction was filtered then purified by RPHPLC (10-50% acetonitrile in water) to give N-((3aR,4R,7S,7aR)-4-(methoxymethyl)-2,2- dimethyltetrahydro-4H-[1,3]dioxolo[4,5-c]pyran-7-yl)acetamide (22 mg, 0.0848 mmol, 69 % yield) and N-((3aR,4R,7S,7aR)-4-(methoxymethyl)-2,2-dimethyltetrahydro-4H-[1,3]dioxolo[4,5-c]pyran- 7-yl)-N-methylacetamide. Yield: 7.0 mg, 21% and 22 mg, 69% respectively. LCMS m / z 274.0 [M+H]+. A solution of N-((3aR,4R,7S,7aR)-4-(methoxymethyl)-2,2-dimethyltetrahydro-4H- [1,3]dioxolo[4,5-c]pyran-7-yl)-N-methylacetamide (1.0 eq, 7.0 mg, 0.0256 mmol) in water (300 mL) was Attorney Ref: 92VF-350823-WO Client Ref: 021WO treated with trifluoroacetic acid (10.0 eq, 0.018 mL, 0.256 mmol). The reaction was filtered then purified by reversed-phase HPLC (5-50% acetonitrile in water) to give N-((3S,4R,5R,6R)-4,5-dihydroxy-6- (methoxymethyl)tetrahydro-2H-pyran-3-yl)-N-methylacetamide (XC22). Yield: 3.4 mg, 57 %. LCMS m / z 234.0 [M+H]+. A solution of N-((3aR,4R,7S,7aR)-4-(methoxymethyl)-2,2-dimethyltetrahydro-4H- [1,3]dioxolo[4,5-c]pyran-7-yl)acetamide (1.0 eq, 22.0 mg, 0.0848 mmol) in water (300 mL) was treated with formic acid (16.0 eq, 51 mL, 1.36 mmol) and after 1h, some starting material was remaining so trifluoroacetic acid (8.4 eq, 51 mL, 0.716 mmol) was added. The reaction was filtered then purified by reversed-phase HPLC (5-50% acetonitrile in water) to give N-((3S,4R,5R,6R)-4,5-dihydroxy-6- (methoxymethyl)tetrahydro-2H-pyran-3-yl)acetamide (XC23). Yield: 6.6 mg, 35%. LCMS m / z 234.0 [M+H]+. Synthesis of XC18: OH O NH2 A vial containing (2R,3R,4R,5S)-5-amino-2-(hydroxymethyl)tetrahydropyran-3,4- diol;hydrochloride (1.5 eq, 53.1 mg, 0.266 mmol), 6-chloro-4-(trifluoromethyl)picolinic acid (1.0 eq, 40.0 mg, 0.177 mmol) and BrettPhos Pd G3 (0.2 eq, 32.2 mg, 0.0355 mmol) was placed under nitrogen in a dry box then anhydrous DMA (1.773 mL) was added followed by an anhydrous solution of sodium tert- butoxide solution (2M in THF, 4.0 eq, 355 mL, 0.709 mmol) and the reaction was sealed then heated to 100 °C for 2h. The reaction was diluted with water and DMSO then purified by reversed-phase HPLC (3- 70% acetonitrile in water w / 0.1% TFA) to give 6-[[(3S,4R,5R,6R)-4,5-dihydroxy-6- (hydroxymethyl)tetrahydropyran-3-yl]amino]-4-(trifluoromethyl)pyridine-2-carboxylic acid as a mixture of regio-isomers. Yield: 15 mg, 24%. LCMS m / z 353.1 [M+H]+. Attorney Ref: 92VF-350823-WO Client Ref: 021WO A solution of the mixture from the synthesis of A (15 mg), propargylamine (3.00 eq, 5.5 mL, 0.0852 mmol), and DIPEA (1.0 eq, 2.9 mg, 0.0284 mmol) in DMSO (0.600 mL) was treated with HATU (1.2 eq, 13.0 mg, 0.0341 mmol) at room temperature. After 2 h, the solution was purified by reversed- phase HPLC (10-50% acetonitrile in water w / 0.1% TFA) to give 6-(((2R,3R,4R,5S)-5-amino-3,4- dihydroxytetrahydro-2H-pyran-2-yl)methoxy)-N-(prop-2-yn-1-yl)-4-(trifluoromethyl)picolinamide. Yield: 3.3 mg, 30%. LCMS m / z 390.0 [M+H]+. A solution of 6-[[(2R,3R,4R,5S)-5-amino-3,4-dihydroxy-tetrahydropyran-2-yl]methoxy]-N-prop- 2-ynyl-4-(trifluoromethyl)pyridine-2-carboxamide (1.0 eq, 3.3 mg, 0.00848 mmol) in DMSO (0.500 mL) was treated with triethylamine (3.0 eq, 3.5 mL, 0.0254 mmol) followed by acetic anhydride (1.0 eq, 0.80 mL, 0.00848 mmol) and the reaction was stirred at room temperature. After 2 h, the reaction was purified by reversed-phase HPLC (10-50% acetonitrile in water w / 0.1% TFA) to give 6-[[(2R,3R,4R,5S)- 5-acetamido-3,4-dihydroxy-tetrahydropyran-2-yl]methoxy]-N-prop-2-ynyl-4-(trifluoromethyl)pyridine-2- carboxamide (XC18). Yield: 1.1 mg, 31%. LCMS m / z 432.2 [M+H]+. Synthesis of XC19: OH O F F F A vial containing (2R,3R,4R,5S)-5-amino-2-(hydroxymethyl)tetrahydropyran-3,4- diol;hydrochloride (example 48-4, 1.5 eq, 53.1 mg, 0.266 mmol), 6-chloro-4-(trifluoromethyl)picolinic acid (1.0 eq, 40.0 mg, 0.177 mmol) and BrettPhos Pd G3 (0.2 eq, 32.2 mg, 0.0355 mmol) was placed under nitrogen in a dry box then anhydrous DMA (1.773 mL) was added followed by an anhydrous solution of sodium tert-butoxide (2M in THF, 4.0 eq, 355 mL, 0.709 mmol) and the reaction was sealed then heated to 100 °C for 2h. The reaction was diluted with water and DMSO then purified by reversed- phase HPLC (3-70% acetonitrile in water w / 0.1% TFA) to give 6-[[(3S,4R,5R,6R)-4,5-dihydroxy-6- (hydroxymethyl)tetrahydropyran-3-yl]amino]-4-(trifluoromethyl)pyridine-2-carboxylic acid as a mixture of regio-isomers. Yield: 15 mg, 24%. LCMS m / z 353.1 [M+H]+. A solution of propargylamine (3.00 eq, 5.5 mL, 0.0852 mmol), 6-[[(3S,4R,5R,6R)-4,5- dihydroxy-6-(hydroxymethyl)tetrahydropyran-3-yl]amino]-4-(trifluoromethyl)pyridine-2-carboxylic acid (1.0 eq, 10.0 mg, 0.0284 mmol) and DIPEA (1.0 eq, 2.9 mg, 0.0284 mmol) in DMSO (0.600 mL) was Attorney Ref: 92VF-350823-WO Client Ref: 021WO treated with HATU (1.2 eq, 13.0 mg, 0.0341 mmol) at room temperature. After 2 h, the solution was purified by reversed-phase HPLC (10-50% acetonitrile in water w / 0.1% TFA) to give 6-[[(3S,4R,5R,6R)- 4,5-dihydroxy-6-(hydroxymethyl)tetrahydropyran-3-yl]amino]-N-prop-2-ynyl-4- (trifluoromethyl)pyridine-2-carboxamide (XC19). Yield: 1.1 mg, 10%. LCMS m / z 390.0 [M+H]+. Synthesis of (2R,3R,4R,5R,6R)-5-((6-(2-(2-(2-(2-aminoethoxy)ethoxy)ethoxy)-1,1- difluoroethyl)pyrazin-2-yl)amino)-2-(hydroxymethyl)-6-propyltetrahydro-2H-pyran-3,4-diol (XB108): 2a SnBu3O OAc O Cl AcO MeOH, AcCl AcO AIBNO10%Pd / C2OH Attorney Ref: 92VF-350823-WO Client Ref: 021WO O NBClO N BnO3HO O NHBoc -ONH2 diyl diacetate (2) A solution of (2S,3R,4R,5R,6R)-3-acetamido-6-(acetoxymethyl)tetrahydro-2H-pyran-2,4,5-triyl triacetate (1, 40 g, 1.0 eq., 103 mmol) in acetyl chloride (120 mL) was cooled to 0 °C. To this, dry methanol (10 mL) was added slowly, and the resultant reaction mixture was stirred at room temperature for 12h. After completion, the reaction mixture was concentrated under reduced pressure, and recrystallized with ethyl acetate and ether (9:1) to afford (2R,3R,4R,5R,6R)-5-acetamido-2-(acetoxymethyl)-6-chlorotetrahydro- 2H-pyran-3,4-diyl diacetate (2) as a white solid. Yield: 32.0 g, 85.0%; LCMS: m / z 366.1 [M+H]+Synthesis of (2R,3R,4R,5S,6R)-5-acetamido-2-(acetoxymethyl)-6-allyltetrahydro-2H-pyran-3,4- diyl diacetate (3) To a solution of (2R,3R,4R,5R,6R)-5-acetamido-2-(acetoxymethyl)-6-chlorotetrahydro-2H-pyran-3,4- diyl diacetate (2, 17.0 g, 46.5 mmol) and allyltributylstannane (100.8 mL, 7.0 eq., 326.0 mmol) in tetrahydrofuran (150 mL) was added azobisisobutyronitrile (2.29 g, 0.3 eq., 13.9 mmol). The resultant reaction mixture was purged with N2gas, and reflux at 80° C for 8h. After completion, tetrahydrofuran was removed under reduced pressure and the residue was partitioned between acetonitrile (120 mL) and pentane (200 mL). The acetonitrile layer was extracted with additional pentane (3x100 mL) to remove organotin compounds, and then concentrated to obtained crude which was purified by silica gel flash chromatography using 50-60% ethyl acetate in heptane as an eluent to afford (2R,3R,4R,5S,6R)-5- acetamido-2-(acetoxymethyl)-6-allyltetrahydro-2H-pyran-3,4-diyl diacetate (3) as off-white semi solid. Yield: 10.2 g, 59.0%; LCMS: m / z 372.4 [M+H]+Synthesis of (2R,3R,4R,5S,6R)-5-acetamido-2-(acetoxymethyl)-6-propyltetrahydro-2H-pyra...

Claims

Attorney Ref: 92VF-350823-WO Client Ref: 021WO WHAT IS CLAIMED IS:

1. A conjugate of Formula I: X(L1)a(L2)b (L3)c(L4)d (L5)e L6Y-B I or a prodrugn is 1 to 10; m is 1 to 10; X is a moiety that binds to asialoglycoprotein receptor (ASGPR); Y is a carrier polypeptide connected to B; B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody; each L1to L6is independently a linking moiety which together provide a linear or branched linker between each X and the Y-B complex; and a, b, c, d, and e are each independently 1, 2, 3, 4, or 5.

2. The conjugate of claim 1, wherein B comprises an extracellular domain of TSHR or a fragment thereof.

3. The conjugate of claim 1 or 2, wherein B comprises a polypeptide having at least 80% (e.g., at least 85%, or at least 90%) sequence identity with a sequence of SEQ ID NOs: 1-7.

4. The conjugate of any one of claims 1-3, wherein B comprises a polypeptide having at least 95% sequence identity with a sequence of SEQ ID NOs: 1-7.

5. The conjugate of any one of claims 1-4, wherein B comprises a polypeptide having at least 98% sequence identity with a sequence of SEQ ID NOs: 1-7.

6. The conjugate of any one of claims 1-5, wherein B comprises a polypeptide of one of SEQ ID NOs: 1-7.

7. The conjugate of any one of claims 1-6, wherein B consists essentially of a polypeptide of one of SEQ ID NOs: 1-7.Attorney Ref: 92VF-350823-WO Client Ref: 021WO 8. The conjugate of claim 1, wherein B has one or more amino acid substitutions selected from R112P, D143P, D151E, V169R, C176S, K250Q, and I253R as compared to a sequence of SEQ ID NO: 1-7.

9. The conjugate of claim 1, wherein B has one or more amino acid substitutions selected from H63C, R112P, D143P, D151E, V169R, I253R as compared to a sequence of SEQ ID NO: 1-7.

10. The conjugate of any one of claims 1 to 9, wherein Y is selected from albumin, albumin binding domain, multimerization domain, Fc domain, Fc (monomer), Fc (dimer), fragments thereof (e.g., synthetic peptides), and variants thereof.

11. The conjugate of any one of claims 1 to 10, wherein Y comprises an albumin, a fragment thereof, or a variant thereof.

12. The conjugate of claim 11, wherein Y comprises human serum albumin (HSA), an HSA domain, bovine serum albumin (BSA), a fragment thereof, or a variant thereof.

13. The conjugate of claim 12, wherein Y is an HSA variant engineered for increased stability, conjugation efficiency (Cys or Lys), and / or FcRn binding.

14. The conjugate of claim 12, wherein Y comprises a polypeptide having 1 to 10 amino acid substitutions, deletions or additions (for example, 1, 2, 3, 4 or 5 amino acid substitutions, deletions or additions) as compared to a sequence of SEQ ID NOs: 8-12, 14 and 15.

15. The conjugate of claim 14, wherein the 1 to 10 amino acid substitutions, deletions or additions are selected from C34A, V54C, K93C, H128C, K262C, and E294C.

16. The conjugate of claim 12, wherein Y comprises a site-specific mutation of a naturally occurring amino acid residue.

17. The conjugate of claim 12, wherein Y comprises a polypeptide having at least 80% (e.g., at least 90%, at least 95%, at least 98%) sequence identity with a sequence of SEQ ID NOs: 8-12, 14 and 15.

18. The conjugate of claim 12, wherein Y comprises a polypeptide of one of SEQ ID NOs: 8-12, 14 and 15.

19. The conjugate of any one of claims 1 to 10, wherein Y comprises a Fc domain, a fragment thereof, or a variant thereof.

20. The conjugate of claim 19, wherein Y comprises Fc (monomer).

21. The conjugate of claim 19, wherein Y comprises Fc (dimer).Attorney Ref: 92VF-350823-WO Client Ref: 021WO 22. The conjugate of any one of claims 19 to 21, wherein Y comprises a Fc domain engineered for increased stability, conjugation efficiency (Cys or Lys), and / or FcRn binding.

23. The conjugate of claim 19, wherein Y comprises a polypeptide having 1 to 10 amino acid substitutions, deletions or additions (for example, 1, 2, 3, 4 or 5 amino acid substitutions, deletions or additions) as compared to a sequence of SEQ ID NO:

15.

24. The conjugate of claim 23, wherein the 1 to 10 amino acid substitutions, deletions or additions are selected from T366W, T366S, X368A, A378C, X407V, and L443C.

25. The conjugate of claim 19, wherein Y comprises a polypeptide having at least 80% (e.g., at least 90%, at least 95%, at least 98%) sequence identity with a sequence of SEQ ID NO:

15.

26. The conjugate of claim 19, wherein Y comprises a polypeptide of SEQ ID NO:

15.

27. The conjugate of any one of claims 1 to 26, wherein Y-B is a chimeric fusion protein.

28. The conjugate of claim 27, wherein Y-B is selected from an Fc-TSHR fusion, and an HSA-TSHR fusion.

29. The conjugate of claim 27 or 28, wherein Y is covalently linked to B via a linker.

30. The conjugate of claim 29, wherein the linker comprises a non-peptidic linking moiety.

31. The conjugate of claim 27, wherein Y is fused directly to B.

32. The conjugate of claim 31, wherein Y is fused indirectly to B via a spacer domain.

33. The conjugate of claim 31, wherein the N-terminal of Y is fused to the C-terminal of B.

34. The conjugate of claim 31, wherein the C-terminal of Y is fused to the N-terminal of B.

35. The conjugate of any one of claims 1 to 26, wherein Y is covalently linked to B via a non-peptidic linking moiety (e.g., a bifunctional linker).

36. The conjugate of any one of claims 1-35, wherein n is from about 2 to about 10.

37. The conjugate of any one of claims 1-36, wherein L is conjugated to one or more lysine residues of Y or B.

38. The conjugate of any one of claims 1-36, wherein L is conjugated to one or more cysteine residues of Y.

39. A conjugate of Formula:Attorney Ref: 92VF-350823-WO Client Ref: 021WO HO OO OHO NH NH Bm is 4 to 6; Y is a carrier polypeptide connected to B, wherein the carrier polypeptide is HSA comprising SEQ ID NO: 15; and B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody, comprising SEQ ID NO:

6.

40. A conjugate of Formula: HO HNO Bm is 4 to 6;Attorney Ref: 92VF-350823-WO Client Ref: 021WO Y is a carrier polypeptide connected to B, wherein the carrier polypeptide is HSA comprising SEQ ID NO: 15; and B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody, comprising SEQ ID NO:

6.

41. A conjugate of Formula: OOO HN O Bm is 4 to 6; Y is a carrier polypeptide connected to B, wherein the carrier polypeptide is HSA comprising SEQ ID NO: 15; and B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody, comprising SEQ ID NO:

6.

42. A conjugate of Formula:Attorney Ref: 92VF-350823-WO Client Ref: 021WO HO HO HO Bm is 4 to 6; Y is a carrier polypeptide connected to B, wherein the carrier polypeptide is HSA comprising SEQ ID NO: 15; and B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody, comprising SEQ ID NO:

6.

43. The conjugate of any of claims 39-42, wherein Y is connected to B via a linking sequence.

44. The conjugate of claim 43, wherein the linking sequence comprises GGGGSGGGGSGGGGS (SEQ ID NO: 16).

45. A conjugate of Formula:Attorney Ref: 92VF-350823-WO Client Ref: 021WO HO OO OHO NH NH Bm is 4 to 6; Y is a carrier polypeptide connected to B, wherein the carrier polypeptide is HSA comprising SEQ ID NO: 15 ; B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody, comprising SEQ ID NO: 6; and Y is connected to B via a linking sequence comprising GGGGSGGGGSGGGGS (SEQ ID NO: 16).

46. A conjugate of Formula: HO HNBAttorney Ref: 92VF-350823-WO Client Ref: 021WO wherein: m is 4 to 6; Y is a carrier polypeptide connected to B, wherein the carrier polypeptide is HSA comprising SEQ ID NO: 15; B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody, comprising SEQ ID NO: 6; and Y is connected to B via a linking sequence comprising GGGGSGGGGSGGGGS (SEQ ID NO: 16).

47. A conjugate of Formula: OOO HN Bm is 4 to 6; Y is a carrier polypeptide connected to B, wherein the carrier polypeptide is HSA comprising SEQ ID NO: 15; B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody, comprising SEQ ID NO: 6; and Y is connected to B via a linking sequence comprising GGGGSGGGGSGGGGS (SEQ ID NO: 16).

48. A conjugate of Formula:Attorney Ref: 92VF-350823-WO Client Ref: 021WO HO HO HO Bm is 4 to 6; Y is a carrier polypeptide connected to B, wherein the carrier polypeptide is HSA comprising SEQ ID NO: 15; B is a thyroid-stimulating hormone receptor (TSHR) polypeptide that binds anti-TSHR autoantibody, comprising SEQ ID NO: 6; and Y is connected to B via a linking sequence comprising GGGGSGGGGSGGGGS (SEQ ID NO: 16).

49. The conjugate of any preceding claim, wherein the conjugate facilitates internalization of anti- TSHR autoantibody into human cells.

50. The conjugate of any preceding claim, wherein the conjugate facilitates accumulation of anti- TSHR autoantibody in an acidic intracellular compartment of human cells.

51. The conjugate of any preceding claim, wherein the conjugate facilitates degradation of anti-TSHR autoantibody by lysosome in the human cells.

52. A method of reducing levels of an extracellular anti-TSHR autoantibody in a patient, the method comprising administering an effective amount of a conjugate according to any one of claims 1 to 45.

53. The method of claim 52, wherein the administration increases internalization of anti-TSHR autoantibody.Attorney Ref: 92VF-350823-WO Client Ref: 021WO 54. The method of claim 53, wherein the internalized anti-TSHR autoantibody accumulates into an acidified endosome compartment.

55. The method of any one of claim 52-54, wherein the administration facilitates degradation of the anti-TSHR autoantibody.

56. The method of any one of claim 52-54, wherein the administration results in decrease of greater than 80% of extracellular anti-TSHR autoantibody level in the patient.

57. The method of any one of claims 52-56, wherein the anti-TSHR autoantibody is M22 or K1-18.

58. A method of treating Graves’ disease in a patient in need thereof, the method comprising administering to the subject an effective amount of a conjugate according to any one of claims 1 to 45.

59. The method of claim 58, wherein the administration increases internalization of anti-TSHR autoantibody.

60. The method of claim 59, wherein the internalized anti-TSHR autoantibody accumulates in an acidified endosome compartment.

61. The method of any one of claim 58-60, wherein the administration facilitates degradation of the anti-TSHR autoantibody.

62. The method of any one of claim 58-61, wherein the administration results in decrease of greater than 80% of extracellular anti-TSHR autoantibody level in the patient.

63. The method of claims 58-52, wherein the anti-TSHR autoantibody is M22 or K1-18.

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