Synthesis of RAS inhibitors

Abstract

The present invention relates to Ras inhibitors and methods for preparing Ras inhibitors.

Description

[Technical Field]

[0001] This invention relates to the synthesis of RAS inhibitors. [Background technology]

[0002] The vast majority of small molecule drugs act by binding to functionally important pockets on target proteins, thereby regulating the activity of those proteins. For example, cholesterol-lowering drugs known as statins bind to the enzymatic active site of HMG-CoA reductase, thus preventing the enzyme from engaging with its substrate. The fact that many such drug / target interaction pairs are known can be misleading to some extent, leading people to believe that, given a reasonable amount of time, effort, and resources, it is possible to discover small molecule modulators for most, if not all, proteins. This is far from the truth. Current estimates suggest that only about 10% of all human proteins are targetable by small molecules (Non-Patent Literature 1). The other 90% are currently considered refractory or refractory to the small molecule drug discovery described above. Such targets are commonly referred to as "undruggable." These undruggable targets represent a vast and voluminous untapped reservoir of clinically important human proteins. Therefore, there is considerable interest in discovering novel molecular modalities that can control the function of such undruggable targets.

[0003] Ras proteins (K-Ras, H-Ras, and N-Ras) play essential roles in various human cancers, and are therefore well-established in the literature as appropriate targets for anti-cancer therapies. In fact, mutations in the Ras protein account for approximately 30% of all human cancers in the United States, many of which are lethal. Dysregulation of the Ras protein due to activating mutations, overexpression, or upstream activation is common in human tumors, and activation of mutations in Ras is frequently found in human cancers. For example, an activating mutation at codon 12 in the Ras protein functions by suppressing both GTPase-activated protein (GAP)-dependent and endogenous GTP hydrolysis rates, which leads to a significant bias of the population of Ras mutant proteins into the "on" (GTP-bound) state (Ras(ON)), resulting in oncogenic MAPK signaling. In particular, Ras exhibits picomolar affinity for GTP, allowing Ras to be activated even in the presence of low concentrations of this nucleotide. Mutations in codon 13 of Ras (e.g., G13C) and codon 61 (e.g., Q61K) also contribute to oncogenic activity in some cancers.

[0004] Despite extensive drug discovery efforts against Ras over the past several decades, only two drugs targeting the K-Ras G12C variant (sotrasib and adaglav) have been approved in the United States. Further efforts are needed to identify additional drugs for cancers driven by various Ras mutations. There is also still a need for simple and scalable synthetic methods for this purpose. [Prior art documents] [Non-patent literature]

[0005] [Non-Patent Document 1] Bojadzic and Buchwald, Curr Top Med Chem 18:674-699 (2019) [Overview of the project]

[0006] The present invention is characterized by a method for preparing compound A, an intermediate useful for the synthesis of compound A, and a method for preparing the intermediate. Compound A, which is a RAS inhibitor, has the following structure: [ka]

[0007] In a first aspect, the present disclosure provides a barium salt of compound 1: [ka]

[0008] In some embodiments, the barium salt has a carboxylic acid:barium ratio of 2:1. In some embodiments, the barium salt has the structure of compound 2: [ka]

[0009] In another aspect, the present disclosure relates to a compound having the structure of compound 3: [ka] or a salt thereof is provided. In some embodiments, the compound or a salt thereof has the structure of compound 3a: [ka]

[0010] In a further embodiment, the present disclosure provides a method for preparing compound 4a. The method comprises contacting compound 4 with one or more ketoreductase enzymes: [ka]

[0011] In some embodiments, compound 4a is formed in a yield of at least 85%. In some embodiments, the method further comprises contacting compound 4 with glucose dehydrogenase. In some embodiments, the method further comprises contacting compound 4 with glucose. In some embodiments, the method further comprises contacting compound 4 with NADP. In some embodiments of the method for preparing compound 4a, the contact is carried out in the presence of a buffer. In some embodiments, the contact is carried out in the presence of dimethyl sulfoxide.

[0012] In yet another embodiment, the present disclosure provides a tetramethylethylenediamine (TMEDA) salt of compound 5: [ka]

[0013] In some embodiments, the TMEDA salt has a carboxylic acid:TMEDA ratio of 2:1.

[0014] In further embodiments, the 1,4-diazabicyclo[2.2.2]octane (DABCO) salt of compound 5. In some embodiments, the DABCO salt has a carboxylic acid:DABCO ratio of 2:1.

[0015] In another aspect, the present disclosure provides a method for preparing compound 6: [ka]

[0016] The method is, a) Step 7 involves bis-N-methylating compound 7 to form compound 7c: [ka] b) The step of carboxylating compound 7c to form compound 7a: [ka] c) Protonating compound 7a to form compound 7b: [ka] d) Protonating compound 7b to form compound 6: [ka] Includes.

[0017] In some embodiments, the bis-N-methylation step (a) includes contacting compound 7 with an alkylating agent and a reducing agent. In some embodiments, the alkylating agent is formaldehyde and the reducing agent is sodium triacetoxyborohydride.

[0018] In some embodiments, the protonation step (c) includes contacting compound 7a with acetic acid.

[0019] In some embodiments, the protonation step (d) includes contacting compound 7b with hydrochloric acid.

[0020] In some embodiments, compound 7a or 7b is used directly in subsequent chemical steps without protonation to form an HCl salt. In some embodiments, compound 6 is used directly in subsequent chemical steps without isolation or purification from the reaction mixture.

[0021] In another aspect, the present disclosure provides a method for preparing compound 8: [ka]

[0022] The method involves compound 9 and compound 10: [ka] This involves contacting the two substances in the presence of an acid and water. In some embodiments, the acid is sulfuric acid.

[0023] In some embodiments, about 4 equivalents of sulfuric acid are used relative to the amount of compound 9.

[0024] In another aspect, the present disclosure provides a method for preparing compound 8: [ka]

[0025] The method is, a) The step of coupling compound 4b and compound 20 to form compound 21: [ka] b) Step of bringing compound 21 and compound 10 into contact to form compound 8: [ka] Includes.

[0026] In some embodiments, the coupling step (a) includes contacting compound 4b with i-PrMgCl·LiCl.

[0027] In some embodiments, the contact step (b) further includes contacting compound 21 and compound 10 with sulfuric acid.

[0028] In yet another embodiment, the present disclosure provides a hemisulfate of compound 8 (compound 8:sulfate in a 2:1 ratio): [ka]

[0029] In some embodiments, the present disclosure provides a method for preparing a hemisulfate of compound 8, the method comprising contacting the free base of compound 8 with sulfuric acid.

[0030] In another aspect, the Disclosure provides a method for preparing compounds 11a and 11b. [ka] The method is, a) A step of reducing compound 22 to form compound 23. [ka] b) Alkylating compound 23 to form a mixture of compounds 11a and 11b. [ka] Includes.

[0031] In another aspect, the Disclosure provides a method for preparing compounds 11a and 11b. [ka] The method is, a) A step of alkylating compound 22 to form compound 24. [ka] b) Reducing compound 24 to form a mixture of compounds 11a and 11b. [ka] Includes.

[0032] In some embodiments, the alkylation step (a) includes contacting compound 22 or compound 23 with diethyl sulfate.

[0033] In some embodiments, the reduction step (b) includes contacting compound 22 or compound 24 with sodium borohydride.

[0034] In yet another aspect, the present disclosure provides a method for separating compound 11a and compound 11b: [ka]

[0035] The method is, a) A step of heating a mixture of compound 11a and compound 11b in a solvent or a mixture of solvents for a certain period of time; b) the step of forming a mixture of a salt of compound 11a and a salt of compound 11b; and c) Separating the mixture of salts of compound 11a and compound 11b. Includes.

[0036] In some embodiments, the heating step (a) is carried out in a mixture of xylene.

[0037] In some embodiments, the salts of compound 11a and compound 11b are hydrochloride salts of compound 11a and compound 11b.

[0038] In some embodiments, separation is carried out as a flow process.

[0039] In a further embodiment, the present disclosure provides a method for preparing compound 3a: [ka]

[0040] The method is, a) Deprotonate compound 3b with a chiral base, thereby forming a diastereomer salt of compound 3b: [ka] b) Reducing the diastereomer salt of compound 3b to form compound 3c: [ka] c) The step of coupling compound 3c with compound 3d or a salt thereof to form compound 3e; [ka] d) Step of hydrolyzing compound 3e to form compound 3a: [ka] Includes.

[0041] In some embodiments, the chiral base is compound 3f. [ka]

[0042] In some embodiments, the method includes protonating compound 3b prior to the reduction step (b). In some embodiments, the protonation step includes contacting compound 3b with hydrochloric acid. In some embodiments, the hydrochloric acid is in an etheric solution. In some embodiments, the hydrochloric acid is in a methyl tert-butyl ether solution.

[0043] In some embodiments, reduction step (b) includes contacting compound 3b with hydrogen gas. In some embodiments, the hydrogen gas is at a pressure of about 4 bar. In some embodiments, reduction step (b) further includes contacting compound 3b with a rhodium catalyst. In some embodiments, reduction step (b) further includes contacting compound 3b with a chiral ligand. In some embodiments, the rhodium catalyst is Rh(COD)2OTf. In some embodiments, the chiral ligand is (S,S)-Et-DuPhos. In some embodiments, less than 0.25 mol% of the rhodium catalyst is used relative to the amount of compound 3b.

[0044] In some embodiments, enzymatic chemistry can be used to obtain enantiomerically concentrated compound 3a. In some embodiments, compound 3a is prepared by enzymatic chiral resolution. In some embodiments, compound 3a is prepared using phenyl ammonia lyase. In some embodiments, compound 3a is prepared using lipase. In some embodiments, compound 3a is prepared using amino acid dehydrogenase. The use of enzymatic chemistry can reduce the costs associated with the use of rhodium catalysts in carrying out asymmetric hydrogenation reactions. The use of enzymatic chemistry can also lead to improved yield and / or reproducibility compared to asymmetric hydrogenation reactions.

[0045] In one embodiment, the present disclosure provides a method for preparing compound A: [ka]

[0046] The method is, a) The step of coupling compound 11a and compound 3a to form compound 12: [ka] b) Deprotecting compound 12 to form compound 13: [ka] c) The step of coupling compound 13 to form compound 14: [ka] d) Step of deprotecting compound 14 to form compound 15: [ka] e) The step of coupling compound 15 and compound 2 to form compound A: [ka] Includes.

[0047] In some embodiments, the method for preparing compound A further includes the step of purifying compound A by recrystallizing compound A. In some embodiments, recrystallization includes contacting compound A with one or more solvents selected from ethyl acetate, water, and diisopropylethylamine, or a mixture thereof. In some embodiments, recrystallization is carried out in a mixture of ethyl acetate and n-heptane.

[0048] In some embodiments, coupling step (a) includes contacting compounds 11a and 3a with EDCI and HOBt. In some embodiments, coupling step (c) is carried out in alumina-treated dioxane. In some embodiments, coupling step (c) includes contacting compound 13 with a palladium catalyst. In some embodiments, the method further includes washing a solution of compound 15 with an aqueous base. In some embodiments, compound 15 is not isolated or purified before coupling step (e).

[0049] In one embodiment, the present disclosure relates to a compound having the structure of compound 12: [ka] or provide a salt thereof.

[0050] In another aspect, the present disclosure relates to a compound having the structure of compound 13: [ka] or provide a salt thereof.

[0051] Definitions and Chemical Terms In this application, unless otherwise clearly indicated by the context, (i) the term “one (a)” means “one or more”; (ii) the term “or” is used to mean “and / or” unless it is explicitly indicated that it means only alternative expressions or that such alternative expressions are mutually exclusive, however this disclosure supports the definitions that refer only to alternative expressions and to “and / or”; (iii) the terms “comprising” and “including” are understood to encompass itemized components or processes, whether presented by themselves or together with one or more additional components or processes; and (iv) where a scope is indicated, it includes endpoints.

[0052] As used herein, the term “approximately” is used to indicate that a value includes the standard deviation of the error of the device or method used to determine the value. In certain embodiments, unless otherwise stated or evident from the content (for example, if such a number may exceed 100% of the possible values), the term “approximately” refers to a range of values ​​that fall within 25%, 20%, 19%, 18%, 17%, 16%, 15%, 14%, 13%, 12%, 11%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, and 1% or less in either direction (above or below) the stated value.

[0053] As used herein, the term "adjacent" in the context of describing adjacent atoms means divalent atoms directly bonded by a covalent bond.

[0054] As used herein, “compounds of the present invention” and similar terms mean, whether expressly stated or not, the Ras inhibitors described herein (e.g., compound A) and intermediates in their synthesis, as well as their salts (e.g., pharmaceutically acceptable salts), solvates, hydrates, stereoisomers (including atropisomers), and tautomers.

[0055] Those skilled in the art will understand that certain compounds described herein may exist in one or more different isomeric forms (e.g., stereoisomers, geometric isomers, atropisomers, tautomers) or isotopic forms (e.g., hydrogen substituted with deuterium, in which one or more atoms are substituted with different isotopes of that atom). Unless otherwise specified or made clear from the context, the described structures can be understood to represent any such isomeric or isotopic forms, individually or in combination.

[0056] The compounds described herein may be asymmetric (e.g., having one or more stereocenters). Any stereoisomers, such as enantiomers and diastereomers, are intended unless otherwise specified. Compounds of this disclosure containing asymmetrically substituted carbon atoms can be isolated in optically active forms or as racemates. Methods for preparing optically active forms from optically active starting materials are known in the art, for example, by resolution of racemic mixtures or stereoselective synthesis. Many geometric isomers, such as olefins and C=N double bonds, may also exist among the compounds described herein, and all such stable isomers are intended in this disclosure. Cis and trans geometric isomers of the compounds of this disclosure are described and may be isolated as mixtures of isomers or as separated isomers.

[0057] In some embodiments, one or more of the compounds described herein can exist in different tautomeric forms. References to such compounds, unless explicitly excluded from the context, include all such tautomeric forms. In some embodiments, tautomeric forms result from the exchange of a single bond with an adjacent double bond and the accompanying movement of a proton. In certain embodiments, the tautomeric forms can be prototropic tautomers, which are isomeric protonation states having the same empirical formula and total charge as the reference form. Examples of moieties having prototropic tautomeric forms include keto-enol pairs, amide-imidic acid pairs, lactam-lactim pairs, enamine-imine pairs, and cyclic forms in which a proton can occupy two or more positions in a heterocyclic system, such as 1H- and 3H-imidazole, 1H-, 2H-, and 4H-1,2,4-triazole, 1H- and 2H-isoindole, and 1H- and 2H-pyrazole. In some embodiments, the tautomeric forms are in equilibrium or can be stereochemically fixed in one form by appropriate substitution. In certain embodiments, the tautomeric forms result from acetal interchange.

[0058] Unless otherwise indicated, the structures shown herein also mean to include compounds that differ only in that one or more isotopically enriched atoms are present. Exemplary isotopes that can be incorporated into the compounds of the present invention include 2 H, 3 H, 11 C, 13 C, 14 C, 13 N, 15 N, 15 O, 17 O, 18 O, 32 P, 33 P, 35 S, 18 F, 36 Cl, 123 I, and 125 I and the like, such as isotopes of hydrogen, carbon, nitrogen, oxygen, phosphorus, sulfur, fluorine, chlorine, and iodine. Isotopically labeled compounds (e.g.,3 H and 14 Compounds labeled with 1C may be useful in compound or substrate tissue distribution assays. Tritium labeling (i.e., 3 H), and carbon-14 (i.e., 14 C) Isotopes may be useful due to their ease of preparation and detection. Furthermore, heavier isotopes, such as deuterium (i.e., 2 Substitution with H) etc. can lead to greater metabolic stability, which may result in certain therapeutic benefits (e.g., longer in vivo half-life or reduced dosage). In some embodiments, one or more hydrogen atoms are 2 H or 3 Replaced by H, or one or more carbon atoms 13 C or 14 It is replaced by carbon-enriched carbon. 15 O, 13 N, 11 C and 18 Positron-emitting isotopes such as fluorine are useful in positron emission tomography (PET) studies to examine substrate receptor occupancy. The preparation of isotopically labeled compounds is known to those skilled in the art. For example, isotopically labeled compounds can generally be prepared by replacing unlabeled reagents with isotopically labeled reagents, following a procedure similar to the procedure disclosed for the compounds of the present invention as described herein.

[0059] As is known from the prior art, many chemical components can be used in various different solid forms, such as amorphous or crystalline forms (e.g., polymorphs, hydrates, solvates). In some embodiments, the compounds of the present invention can be used in any such form, including any solid form. In some embodiments, the compounds described or explained herein can be provided or used in hydrate or solvate form.

[0060] In various parts of this specification, substituents of the compounds of this disclosure are disclosed by group or range. This disclosure is specifically intended to include each individual partial combination of members of such groups and ranges. For example, the term “C1-C6 alkyl” is specifically intended to disclose methyl, ethyl, C3 alkyl, C4 alkyl, C5 alkyl, and C6 alkyl individually. Furthermore, where a compound includes multiple positions in which substituents are disclosed by group or range, this disclosure is intended to include individual compounds and groups of compounds (e.g., genus and sub-genus) including each and all individual member subcombinations at each position, unless otherwise specified.

[0061] The term “optionally substituted X” (e.g., optionally substituted alkyl) is intended to be equivalent to “X which is optionally substituted” (e.g., “alkyl which is optionally substituted”). It is not intended to mean that the feature “X” (e.g., alkyl) itself is optional. As described herein, a particular compound of interest may contain one or more “optionally substituted” moieties. In general, “substituted” means that one or more hydrogens of a given moiety are replaced by a suitable substituent, e.g., one of the substituents or groups described herein, regardless of whether the term “optionally” precedes it. Unless otherwise indicated, an “optionally substituted” group may have a suitable substituent at each of its substitutable positions, and if two or more positions of any given structure can be replaced by two or more substituents selected from a particular group, the substituents are either the same at all positions or different at all positions. For example, in the term "optionally substituted C1-C6 alkyl-C2-C9 heteroaryl," the alkyl moiety, the heteroaryl moiety, or both may be optionally substituted. The substituent combinations conceivable in this disclosure preferably result in the formation of stable or chemically suitable compounds. As used herein, the term "stable" means a compound that remains substantially unchanged when subjected to conditions anticipating the production, detection, and, in certain embodiments, their recovery, purification, and use for one or more purposes disclosed herein.

[0062] Suitable monovalent substituents on the replaceable carbon atoms of the "optionally substituted" group are, independently, deuterium, halogen, and -(CH2)O-4R ° ,-(CH2)0-4OR ° -O(CH2) 0-4Ro, -O-(CH2)O-4C(O)OR°;-(CH2)O-4CH(OR°)2;-(CH2)O-4SR°;-(CH2)O-4Ph[May be substituted with R°];-(CH2)O-4O(CH2)O-1Ph[May be substituted with R°];-CH=CHPh[May be substituted with R°];-(CH2)O-4O(CH2)O-1-pyridyl[May be substituted with R°]. ]; 4-8 member saturated or unsaturated heterocycloalkyl (e.g., pyridyl); 3-8 member saturated or unsaturated cycloalkyl (e.g., cyclopropyl, cyclobutyl, or cyclopentyl); -NO2; -CN; -N3; ​​-(CH2)O-4N(R°)2; -(CH2)O-4N(R°)C(O)R°; -N(R°)C(S)R°; -(CH2)O-4N(R °)C(O)NR°2;-N(R°)C(S)NR°2;-(CH2)0-4N(R°)C(O)OR°;-N(R°)N(R°)C(O)R°;-N(R°)N(R°)C(O)N R°2;-N(R°)N(R°)C(O)OR°;-(CH2)0-4C(O)R°;-C(S)R°;-(CH2)0-4C(O)OR°;-(CH2)0-4-C(O)-N(R o )2;-(CH2)O-4-C(O)-N(R o )-S(O)2-R o;-C(NCN)NR°2;-(CH2)0-4C(O)SR°;-(CH2)0-4C(O)OSiR°3;-(CH2)0-4OC(O)R°;-OC(O)(CH2)0-4SR°;-SC(S)SR°;-(CH2)0- 4SC(O)R°;-(CH2)0-4C(O)NR°2;-C(S)NR°2;-C(S)SR°;-(CH2)0-4OC(O)NR°2;-C(O)N(OR°)R°;-C(O)C(O)R°;-C(O)CH2C(O)R °;-C(NOR°)R°;-(CH2)0-4SSR°;-(CH2)0-4S(O)2R°;-(CH2)0-4S(O)2OR°;-(CH2)0-4OS(O)2R°;-S(O)2NR°2;-(CH2)0-4S(O )R°;-N(R°)S(O)2NR°2;-N(R°)S(O)2R°;-N(OR°)R°;-C(NOR°)NR°2;-C(NH)NR°2;-P(O)2R°;-P(O)R°2;-P(O)(OR°)2;-OP(O) R°2;-OP(O)(OR°)2;-OP(O)(OR°)R°, -SiR°3;-(C1-4 linear or branched alkylene)ON(R°)2; or -(C1-4 linear or branched alkylene)C(O)ON(R°)2, where each R° may be substituted as defined below, independently of hydrogen, -C1-6 aliphatic, -CH2Ph, -O(CH2)0-1Ph, -CH2-(5-6 membered heteroaryl ring), or nitrogen, oxygen, or A 3-6 member saturated, partially unsaturated, or aryl ring having 0-4 heteroatoms independently selected from sulfur, or, notwithstanding the above definition, two independently existing R°s, together with the atom(s) between them, form a 3-12 member saturated, partially unsaturated, or aryl monocyclic or bicyclic ring having 0-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur, which may be substituted as defined below.

[0063] Suitable monovalent substituents on R° (or the ring formed by using two independently existing R° atoms together with the atoms in between) are, independently, halogens, -(CH2)O-2R ● ,-(HaroR ●), -(CH2)O-2OH, -(CH2)O-2OR ● ,-(CH2)0-2CH(OR ● )2;-O(HaroR ● ), -CN, -N3, -(CH2)0-2C(O)R ● , -(CH2)0-2C(O)OH, -(CH2)0-2C(O)OR ● ,-(CH2)0-2SR ● , -(CH2)0-2SH, -(CH2)0-2NH2, -(CH2)0-2NHR ● ,-(CH2)0-2NR ● 2, -NO2, -SiR ● 3. -OSiR ● 3. -C(O)SR ● , -(C1-4 straight-chain or branched-chain alkylene)C(O)OR ● , or -SSR ● It can be, and in the formula, each R ● It is either unsubstituted or, if preceded by "halo", substituted by only one or more halogens, and independently selected from C1-4 aliphatic, -CH2Ph, -O(CH2)0-1Ph, or a 5-6 member saturated, partially unsaturated, or aryl ring having 0-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur. Preferred divalent substituents on the saturated carbon atom of R° include =O and =S.

[0064] Suitable divalent substituents on the saturated carbon atom of the "optionally substituted" group are: =O, =S, =NNR * 2. =NNHC(O)R * ,=NNHC(O)OR * ,=NNHS(O)2R * ,=NR * 、=NOR * , -O(C(R * 2))2-3O-, or -S(C(R * 2))2-3S- are listed, and in the formula, R exists independently in each case. *This is selected from hydrogen, a C1-6 aliphatic which can be substituted as defined below, or an unsubstituted 5-6 member saturated, partially unsaturated, or aryl ring having 0-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur. A preferred divalent substituent bonded to the vicinal substituteable carbon of the "optionally substituted" group is -O(CR * 2) 2-3O- is an example, and in the formula, each R exists independently. * This is selected from hydrogen, a C1-6 aliphatic which may be substituted as defined below, or an unsubstituted 5-6 member saturated, partially unsaturated, or aryl ring having 0-4 heteroatoms independently selected from nitrogen, oxygen, or sulfur.

[0065] R * Suitable substituents on the aliphatic group include halogens and -R ● ,-(HaroR ● ), -OH, -OR ● ,-O(HaroR ● ), -CN, -C(O)OH, -C(O)OR ● -NH2, -NHR ● , -NR ● 2, or -NO2, in the formula, each R ● It is either unsubstituted, or, if preceded by "halo", substituted by only one or more halogens, and is independently a 5-6 member saturated, partially unsaturated, or aryl ring having 0-4 heteroatoms independently selected from C1-4 aliphatic, -CH2Ph, -O(CH2)0-1Ph, or nitrogen, oxygen, or sulfur.

[0066] A suitable substituent on the substituted nitrogen of the "optionally substituted" group is -R † , including, -NR † 2, -C(O)R † , -C(O)OR † ,-C(O)C(O)R † -C(O)CH2C(O)R † -S(O)2R † -S(O)2NR † 2, -C(S)NR † 2. -C(NH)NR† 2. or -N(R † )S(O)2R † ; wherein each R † is independently hydrogen, a C1-6 aliphatic group which may be substituted as defined below, unsubstituted -OPh, or an unsubstituted 3-6 membered saturated, partially unsaturated or aryl ring having 0-4 heteroatoms independently selected from nitrogen, oxygen or sulfur, or, regardless of the above definition, two R † existing independently may together with the atom(s) intervening therebetween form an unsubstituted 3-12 membered saturated, partially unsaturated or aryl monocyclic or bicyclic ring having 0-4 heteroatoms independently selected from nitrogen, oxygen or sulfur.

[0067] R † Suitable substituents on the aliphatic group of are independently halogen, -R ● , -(haloR ● ), -OH, -OR ● , -O(haloR ● ), -CN, -C(O)OH, -C(O)OR ● , -NH2, -NHR ● , -NR ● 2, or -NO2, wherein each R ● is unsubstituted or, when "halo" precedes, is substituted only by one or more halogens and is independently a C1-4 aliphatic group, -CH2Ph, -O(CH2)0-1Ph, or a 5-6 membered saturated, partially unsaturated or aryl ring having 0-4 heteroatoms independently selected from nitrogen, oxygen or sulfur. Suitable divalent substituents on the saturated carbon atom of R † include =O and =S.

[0068] As used herein, the term "acetyl" means the group -C(O)CH3.

[0069] As used herein, the term "alkoxy" means -O-C1-C 20 alkyl group, and the alkoxy group is bonded to the remainder of the compound through an oxygen atom.

[0070] As used herein, the term “alkyl” means a saturated, linear, or branched monovalent hydrocarbon group containing 1 to 20 (e.g., 1 to 10, or 1 to 6) carbon atoms. In some embodiments, the alkyl group is unbranched (i.e., linear), and in some embodiments, the alkyl group is branched. Alkyl groups are exemplified by, but are not limited to, methyl, ethyl, n-propyl and isopropyl, n-butyl, sec-butyl, isobutyl and tert-butyl, and neopentyl.

[0071] As used herein, the term "alkylene" refers to a saturated divalent hydrocarbon group derived from a saturated hydrocarbon, either linear or branched, by removing two hydrogen atoms, exemplified by methylene, ethylene, isopropylene, and the like. x -C y "Alkylene" refers to an alkylene group having x to y carbon atoms. Exemplary values ​​for x are 1, 2, 3, 4, 5, and 6, and exemplary values ​​for y are 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, 14, 16, 18, or 20 (e.g., C1-C6, C1-C 10 , C2-C 20 , C2-C6, C2-C 10 , or C2-C 20 Alkylene). In some embodiments, the alkylene may be further substituted with one, two, three, or four substituents as defined herein.

[0072] As used herein, the term “alkenyl” means, unless otherwise specified, a monovalent linear or branched group of 2 to 20 carbon atoms (e.g., 2 to 6 or 2 to 10 carbon atoms) containing one or more carbon-carbon double bonds, exemplified by ethenyl, 1-propenyl, 2-propenyl, 2-methyl-1-propenyl, 1-butenyl, and 2-butenyl. Alkenyls include both cis and trans isomers. As used herein, the term “alkenylene” means, unless otherwise specified, a divalent linear or branched group of 2 to 20 carbon atoms (e.g., 2 to 6 or 2 to 10 carbon atoms) containing one or more carbon-carbon double bonds.

[0073] As used herein, the term "alkynyl" refers to a monovalent linear or branched group consisting of 2 to 20 carbon atoms (e.g., 2 to 4, 2 to 6, or 2 to 10 carbon atoms) containing a carbon-carbon triple bond, as exemplified by ethynyl and 1-propynyl.

[0074] As used herein, the term "amino" means -N(R † )2, for example, represents -NH2 and -N(CH3)2.

[0075] As used herein, the term "aminoalkyl" refers to an alkyl moiety in which one or more carbon atoms are substituted with one or more amino moieties.

[0076] As used herein, the term “aryl” refers to a monovalent monocyclic, bicyclic, or polycyclic ring system formed by carbon atoms, wherein the ring bonded to the pendant group is aromatic. Examples of aryl groups include phenyl, naphthyl, phenantrenyl, and anthracenyl. The aryl ring may be bonded to its pendant group by any heteroatom or carbocyclic atom that provides a stable structure, and unless otherwise specified, any of the ring atoms may be optionally substituted.

[0077] The term "Boc" refers to structure [ka] This refers to a tert-butyloxycarbonyl or tert-butoxycarbonyl protecting group having a tert-butyloxycarbonyl protecting group.

[0078] As used herein, the term "C0" represents a bond. For example, part of the term -N(C(O)-(C0-C5alkylene-H)- includes -N(C(O)-(C0alkylene-H)-, which is also represented by -N(C(O)-H)-.

[0079] As used herein, the terms "carbocyclic" and "carbocyclyl" refer to a monovalent C3- substituted with optional substitution. 12 This refers to monocyclic, bicyclic, or tricyclic structures, which may be bridged, condensed, or spirocyclic, where all rings are formed of carbon atoms and at least one ring is non-aromatic. Examples of carbocyclic structures include cycloalkyl, cycloalkenyl, and cycloalkynyl groups. Examples of carbocyclyl groups include cyclohexyl, cyclohexenyl, cyclooctinyl, 1,2-dihydronaphthyl, 1,2,3,4-tetrahydronaphthyl, fluorenyl, indenyl, indanyl, and dekalinyl. A carbocyclic ring can be bonded to its pendant group at any ring atom that results in a stable structure, and unless otherwise specified, any of the ring atoms may be optionally substituted.

[0080] As used herein, the term "carbonyl" refers to a C(O) group, which can also be represented as C=O.

[0081] As used herein, the term "carboxyl" means -CO2H, (C=O)(OH), COOH, or C(O)OH, or the corresponding aprotonated group.

[0082] The term "Cbz" is, [ka] This refers to a benzyloxycarbonyl protecting group having the structure.

[0083] As used herein, the term "cyano" refers to the -CN group.

[0084] As used herein, the term "cycloalkyl" means a monovalent saturated cyclic hydrocarbon group, which may be crosslinked, condensed, or a spirocyclic group having 3 to 8 carbon atoms, unless otherwise specified, and is exemplified by cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, and cycloheptyl.

[0085] As used herein, the term "cycloalkenyl" means a monovalent non-aromatic saturated cyclic hydrocarbon group, which, unless otherwise specified, may be crosslinked, condensed, or a spirocyclic group having 3 to 8 carbon atoms and containing one or more carbon-carbon double bonds.

[0086] As used herein, the term “diastereomer” means a stereoisomer that is not a mirror image of another and cannot be superimposed on another.

[0087] As used herein, “enantiomer” means each individual optically active form of the compound of the present invention having at least 80% (i.e., at least 90% of one enantiomer and up to 10% of the other enantiomer), preferably at least 90%, and more preferably at least 98% optical purity or enantiomer excess (measured by methods standard in the art).

[0088] As used herein, the term "haloacetyl" means an acetyl group in which at least one hydrogen atom is substituted with a halogen.

[0089] As used herein, the term "haloalkyl" refers to an alkyl moiety in which one or more carbon atoms are substituted with one or more identical or different halogen moieties.

[0090] As used herein, the term "halogen" refers to a halogen selected from bromine, chlorine, iodine, or fluorine.

[0091] As used herein, the term “heteroalkyl” refers to an “alkyl” group (as defined herein) in which at least one carbon atom is replaced by a heteroatom (e.g., an O, N, or S atom). The heteroatom may appear in the middle or at the ends of the radical.

[0092] As used herein, the term “heteroaryl” refers to a monovalent monocyclic or polycyclic cyclic structure containing at least one complete aromatic ring. That is, these contain 4n+2 π electrons within the monocyclic or polycyclic ring system and contain at least one ring heteroatom selected from N, O, or S within the aromatic ring. Exemplary unsubstituted heteroaryl groups have 1 to 12 (e.g., 1 to 11, 1 to 10, 1 to 9, 2 to 12, 2 to 11, 2 to 10, or 2 to 9) carbon atoms. The term “heteroaryl” also includes bicyclic, tricyclic, and tetracyclic groups in which any of the above heteroaromatic rings are fused to one or more aryl or carbocyclic rings, such as a phenyl ring or a cyclohexane ring. Examples of heteroaryl groups include, but are not limited to, pyridyl, pyrazolyl, benzoxazolyl, benzimidazolyl, benzothiazolyl, imidazolyl, thiazolyl, quinolinyl, tetrahydroquinolinyl, and 4-azaindylol. The heteroaryl ring can be bonded to its pendant group at any ring atom that provides a stable structure, and unless otherwise specified, any of the ring atoms may be optionally substituted. In some embodiments, the heteroaryl is substituted with 1, 2, 3, or 4 substituents.

[0093] As used herein, the term “heterocycloalkyl” refers to a monovalent monocyclic, bicyclic, or polycyclic ring system, which may be bridged, condensed, or spirocyclic, in which at least one ring is non-aromatic, and the non-aromatic ring contains 1, 2, 3, or 4 heteroatoms independently selected from the group consisting of nitrogen, oxygen, and sulfur. Five-membered rings have 0 to 2 double bonds, and six-membered and seven-membered rings have 0 to 3 double bonds. Exemplary unsubstituted heterocycloalkyl groups have 1 to 12 (e.g., 1 to 11, 1 to 10, 1 to 9, 2 to 12, 2 to 11, 2 to 10, or 2 to 9) carbon atoms. The term “heterocycloalkyl” also refers to heterocyclic compounds having a bridged polycyclic structure in which one or more carbons or heteroatoms bridge two non-adjacent members of a monocyclic ring, e.g., a quinuclidinyl group. The term "heterocycloalkyl" includes bicyclic, tricyclic, and tetracyclic groups in which any of the above heterocyclic rings is fused to one or more aromatic, carbocyclic, heteroaromatic, or heterocyclic rings, such as an aryl ring, cyclohexane ring, cyclohexene ring, cyclopentane ring, cyclopentene ring, pyridine ring, or pyrrolidine ring. Examples of heterocycloalkyl groups are pyrrolidinyl, piperidinyl, 1,2,3,4-tetrahydroquinolinyl, decahydroquinolinyl, dihydropyrrolopyridine, and decahydronaphthilidinyl. Heterocycloalkyl rings can be bonded to their pendant group at any ring atom that results in a stable structure, and unless otherwise specified, any of the ring atoms may be optionally substituted.

[0094] As used herein, the term "hydroxy" refers to the -OH group.

[0095] As used herein, the term "hydroxyalkyl" refers to an alkyl moiety in which one or more carbon atoms are substituted with one or more -OH moieties.

[0096] As used herein, the term “isomer” means any tautomer, stereoisomer, atropisomer, enantiomer, or diastereomer of any compound of the present invention. Compounds of the present invention may have one or more chiral centers or double bonds and are therefore recognized to exist as stereoisomers, e.g., double bond isomers (i.e., geometric E / Z isomers), or diastereomers (e.g., enantiomers (i.e., (+) or (-), or cis / trans isomers)). According to the present invention, the chemical structures illustrated herein, i.e., compounds of the present invention, are recognized to exist as all corresponding stereoisomers, i.e., stereoisomerically pure forms (e.g., geometrically pure, enantiomerically pure, or diastereoisomerically pure forms) and enantiomers. The present invention encompasses both enantiomers and mixtures of stereoisomers, such as racemic compounds. Mixtures of enantiomers and stereoisomers of the compounds of the present invention can typically be separated into their constituent enantiomers or stereoisomers by well-known methods, such as chiral phase gas chromatography, chiral phase high-performance liquid chromatography, crystallization of the compound as a chiral salt complex, or crystallization of the compound in a chiral solvent. Enantiomers and stereoisomers can also be obtained from stereoisomerically or enantiomerically pure intermediates, reagents, and catalysts by well-known asymmetric synthesis methods.

[0097] As used herein, the term “stereoisomer” means all possible different isomeric and structural forms that a compound may have (e.g., any compound of any formula described herein), in particular all possible stereochemical and structural isomeric forms of the basic molecular structure, including atropisomers, all diastereomers, enantiomers, or conformational isomers. Some of the compounds of the present invention may exist in different tautomers, all of which are included in the scope of the present invention.

[0098] As used herein, the term "sulfonyl" refers to the -S(O)2- group.

[0099] As used herein, the term "thiocarbonyl" means a -C(S)- group.

[0100] As used herein, the term "inon" means structure [ka] [wherein R is any chemically suitable substituent as described herein.] refers to a group containing ]

[0101] Those skilled in the art reading this disclosure will understand that certain compounds described herein may be provided or available in any of a variety of forms, such as salts, protected forms, prodrugs, esters, isomers (e.g., optical or structural isomers), and isotopic forms. In some embodiments, reference to a particular compound may relate to a particular form of that compound. In some embodiments, reference to a particular compound may relate to that compound in any form. In some embodiments, for example, a preparation of a single stereoisomer of a compound may be considered a different form of the compound from a racemic mixture of the compound; a particular salt of a compound may be considered a different form from another salt form of the compound; a preparation containing one structural isomer of a double bond ((Z) or (E)) may be considered a different form from one containing the other structural isomer of the double bond ((E) or (Z)); and a preparation in which one or more atoms are isotopes different from those present in the reference preparation may be considered a different form. [Brief explanation of the drawing]

[0102] [Figure 1] This diagram shows a flow process for separating compound 11b from the undesirable atropisomer compound 11a. [Modes for carrying out the invention]

[0103] Provided herein are a synthetic method and intermediates for preparing Ras inhibitor compound A or a salt thereof. The method and intermediates may be useful in achieving higher yield, higher chemical purity, and / or higher stereoisomer purity, as well as lower cost, in the preparation of compound A. Further synthetic details are provided in the examples. The structure of compound A is shown below. [ka]

[0104] The compounds described herein may be prepared using the methods described herein and / or known organic, inorganic, or enzymatic processes. The synthetic methods may employ the use of commercially available starting materials or starting materials prepared by processes known to those skilled in the art of organic synthesis. These methods include, but are not limited to, the methods described in the following sections, as well as those described in WO2021 / 091982 and WO2022 / 235864, the disclosures of which are incorporated herein by reference.

[0105] Synthesis method In a further embodiment, the present disclosure provides a method for preparing compound 4a. The method comprises contacting compound 4 with one or more ketoreductase enzymes: [ka]

[0106] In some embodiments, compound 4a is formed in a yield of at least 85%. In some embodiments, the method further comprises contacting compound 4 with glucose dehydrogenase. In some embodiments, the method further comprises contacting compound 4 with glucose. In some embodiments, the method further comprises contacting compound 4 with NADP. In some embodiments of the method for preparing compound 4a, the contact is carried out in the presence of a buffer. In some embodiments, the contact is carried out in the presence of dimethyl sulfoxide. In some embodiments, compound 4a is prepared according to the following scheme: [ka]

[0107] In another aspect, the present disclosure provides a method for preparing compound 6: [ka]

[0108] The method is, a) Step 7 involves bis-N-methylating compound 7 to form compound 7c: [ka] b) The step of carboxylating compound 7c to form compound 7a: [ka] c) Protonating compound 7a to form compound 7b: [ka] d) Protonating compound 7b to form compound 6: [ka] Includes.

[0109] In some embodiments, the bis-N-methylation step (a) includes contacting compound 7 with an alkylating agent and a reducing agent. In some embodiments, the alkylating agent is formaldehyde and the reducing agent is sodium triacetoxyborohydride. In some embodiments, the bis-N-methylation step (a) is carried out in a solvent (e.g., an etheric solvent, e.g., 2-methyltetrahydrofuran). In some embodiments, the bis-N-methylation step (a) is carried out according to the following scheme: [ka]

[0110] In some embodiments, the carboxylation step (b) includes contacting compound 7c with a base. In some embodiments, the base is LiHMDS. In some embodiments, contacting compound 7c with a base is carried out below room temperature (e.g., below 20°C, below 10°C, below 0°C, below -10°C, below -20°C, below -30°C, below -40°C, below -50°C, or below -60°C). In some embodiments, contacting compound 7c with a base is carried out at -80 to -65°C. In some embodiments, after contacting compound 7c with a base, compound 7c is then contacted with carbon dioxide (e.g., a carbon dioxide case or dry ice).

[0111] In some embodiments, the carboxylation step (b) is carried out according to the following scheme: [ka]

[0112] In some embodiments, the protonation step (c) includes contacting compound 7a with acetic acid. In some embodiments, the protonation step (d) includes contacting compound 7b with hydrochloric acid. In some embodiments, compound 7a or 7b is used directly in subsequent chemical steps without protonation to form an HCl salt. In some embodiments, compound 6 is used directly in subsequent chemical steps without isolation or purification from the reaction mixture.

[0113] In some embodiments, the protonation step (d) and the protonation step (d) are carried out according to the following scheme: [ka]

[0114] In another aspect, the present disclosure provides a method for preparing compound 8: [ka]

[0115] The method involves compound 9 and compound 10: [ka] This involves contacting the two substances in the presence of an acid and water. In some embodiments, the acid is sulfuric acid.

[0116] In some embodiments, about 4 equivalents of sulfuric acid are used relative to the amount of compound 9. In some embodiments, contact between compound 9 and compound 10 is carried out above room temperature (e.g., above 20°C, above 30°C, above 40°C, above 50°C, above 60°C, above 70°C, above 80°C, above 90°C, or above 100°C). In some embodiments, compound 8 is prepared according to the following scheme: [ka]

[0117] In another aspect, the present disclosure provides a method for preparing Compound 8:

Chemical Structure

[0118] The method comprises: a) coupling Compound 4b and Compound 20 to form Compound 21:

Chemical Structure

Chemical Structure

[0119] In yet another aspect, the present disclosure provides the hemisulfate salt of Compound 8 (Compound 8:sulfate salt in a 2:1 ratio):

Chemical Structure

[0120]

Chemical Structure

[0121] ​In some embodiments, the present disclosure provides a method for preparing a hemisulfate of compound 8, the method comprising contacting the free base of compound 8 with sulfuric acid. In some embodiments, the contact step involves heating at 80°C ± 15°C for 5 hours, followed by maintaining at 30°C ± 15°C for 16 hours.

[0122] In another aspect, the Disclosure provides a method for preparing compounds 11a and 11b. [ka] The method is, a) A step of reducing compound 22 to form compound 23. [ka] b) Alkylation of compound 23 to form a mixture of compounds 11a and 11b. [ka] Includes.

[0123] In some embodiments, the reduction step (a) includes a reducing agent. In some embodiments, the reducing agent is sodium borohydride. In some embodiments, the reduction step (a) is maintained at a temperature of 25°C ± 10°C. In some embodiments, the reduction step (a) is carried out according to the following scheme: [ka]

[0124] In some embodiments, alkylation step (b) includes contacting compound 23 with diethyl sulfate (DES). In some embodiments, alkylation step (b) includes precipitation of compound 11 with an inorganic acid. In some embodiments, alkylation step (b) is carried out according to the following scheme: [ka]

[0125] In another aspect, the present disclosure provides a method for preparing compounds 11a and 11b,

Chemical Structure

Chemical Structure

Chemical Structure

[0126] In some embodiments, the alkylation step (a) comprises contacting compound 22 with diethyl sulfate. In some embodiments, the alkylation step (a) is carried out according to the following scheme:

Chemical Structure

[0127] In some embodiments, the reduction step (b) comprises contacting compound 24 with a reducing agent. In some embodiments, the reducing agent is sodium borohydride. In some embodiments, the reduction step (b) comprises precipitating compound 11 with an inorganic acid. In some embodiments, the reduction step (b) is carried out according to the following scheme:

Chemical Structure

[0128] In yet another aspect, the present disclosure provides a method for separating compound 11a and compound 11b: [ka]

[0129] The method is, a) A step of heating a mixture of compound 11a and compound 11b in a solvent or a mixture of solvents for a certain period of time; b) the step of forming a mixture of a salt of compound 11a and a salt of compound 11b; and c) Separating the mixture of salts of compound 11a and compound 11b. Includes.

[0130] In some embodiments, heating step (a) is carried out in a mixture of xylene. In some embodiments, heating step (a) is carried out at a temperature above 50°C (e.g., above 75°C, above 100°C, above 125°C, or 140°C). In some embodiments, two volumes of xylene are used. In some embodiments, heating step (a) is carried out for a time longer than about one hour (e.g., about one hour, about two hours, about three hours, or about four hours). In some embodiments, separation is carried out as a flow process.

[0131] In some embodiments, the salts of compound 11a and compound 11b are hydrochloride salts of compound 11a and compound 11b. In some embodiments, the hydrochloride salts of compound 11a and compound 11b are formed in a solvent. In some embodiments, the solvent is an alcoholic solvent (e.g., isopropanol).

[0132] In some embodiments, the method for separating compound 11a and compound 11b further includes heating a mixture of salts of compound 11a and compound 11b. In some embodiments, the heating of the salt mixture is carried out in a solvent (e.g., an alcoholic solvent such as isopropanol). In some embodiments, the heating of the salt mixture is carried out at a temperature above 50°C (e.g., above 60°C, above 70°C, or about 80°C).

[0133] In a further embodiment, the present disclosure provides a method for preparing compound 3a: [ka]

[0134] The method is, a) Deprotonate compound 3b with a chiral base, thereby forming a diastereomer salt of compound 3b: [ka] b) Reducing the diastereomer salt of compound 3b to form compound 3c: [ka] c) The step of coupling compound 3c with compound 3d or a salt thereof to form compound 3e; [ka] d) Step of hydrolyzing compound 3e to form compound 3a: [ka] Includes.

[0135] In some embodiments, the chiral base is compound 3f. [ka]

[0136] In some embodiments, the method includes protonating compound 3b prior to the reduction step (b). In some embodiments, the protonation step includes contacting compound 3b with hydrochloric acid. In some embodiments, the hydrochloric acid is in an etheric solution. In some embodiments, the hydrochloric acid is in a methyl tert-butyl ether solution.

[0137] In some embodiments, reduction step (b) includes contacting compound 3b with hydrogen gas. In some embodiments, the hydrogen gas is at a pressure greater than 1 bar (e.g., greater than 2 bar, greater than 3 bar, about 2 bar, about 3 bar, or about 4 bar). In some embodiments, the hydrogen gas is at a pressure of about 4 bar. In some embodiments, reduction step (b) further includes contacting compound 3b with a rhodium catalyst. In some embodiments, reduction step (b) further includes contacting compound 3b with a chiral ligand. In some embodiments, the rhodium catalyst is Rh(COD)2OTf. In some embodiments, the chiral ligand is (S,S)-Et-DuPhos. In some embodiments, less than 10 mol% of the rhodium catalyst is used relative to the amount of compound 3b (e.g., less than 5 mol%, less than 2.5 mol%, less than 1 mol%, less than 0.75 mol%, less than 0.5 mol%, or less than 0.25 mol%). In some embodiments, less than 0.25 mol% (e.g., about 0.20 mol%, about 0.15 mol%, or about 0.10 mol%) of rhodium catalyst is used relative to the amount of compound 3b. In some embodiments, reduction step (c) is carried out in a solvent (e.g., an alcoholic solvent such as methanol). In some embodiments, reduction step (c) is carried out according to the following scheme: [ka]

[0138] In some embodiments, coupling step (d) includes contacting compounds 3c and 3d with a coupling reagent (e.g., EDCI). In some embodiments, coupling step (d) further includes contacting compounds 3c and 3d with HOBt.

[0139] In some embodiments, the coupling step (d) is carried out according to the following scheme: [ka]

[0140] In some embodiments, hydrolysis step (e) includes contacting compound 3e with a hydroxide salt. In some embodiments, the hydroxide salt is lithium hydroxide. In some embodiments, hydrolysis step (e) is carried out according to the following scheme: [ka]

[0141] In some embodiments, enzymatic chemistry can be used to obtain enantiomerically concentrated compound 3a. In some embodiments, compound 3a is prepared by enzymatic chiral resolution. In some embodiments, compound 3a is prepared using phenyl ammonia lyase. In some embodiments, compound 3a is prepared using lipase. In some embodiments, compound 3a is prepared using amino acid dehydrogenase. The use of enzymatic chemistry can reduce the costs associated with the use of rhodium catalysts in carrying out asymmetric hydrogenation reactions. The use of enzymatic chemistry can also lead to improved yield and / or reproducibility compared to asymmetric hydrogenation reactions.

[0142] In one embodiment, the present disclosure provides a method for preparing compound A: [ka]

[0143] The method is, a) The step of coupling compound 11a and compound 3a to form compound 12: [ka] b) Deprotecting compound 12 to form compound 13: [ka] c) The step of coupling compound 13 to form compound 14: [ka] e) Step of deprotecting compound 14 to form compound 15: [ka] e) The step of coupling compound 15 and compound 2 to form compound A: [ka] Includes.

[0144] In some embodiments, coupling step (a) includes contacting compound 11a and compound 3a with EDCI and HOBt. In some embodiments, coupling step (a) further includes contacting compound 11a and compound 3a with one or more bases. In some embodiments, coupling step (a) includes contacting compound 11a and compound 3a with DIPEA. In some embodiments, coupling step (a) includes contacting compound 11a and compound 3a with DMAP. In some embodiments, coupling step (a) is carried out according to the following scheme: [ka]

[0145] In some embodiments, the deprotection step (b) includes contacting compound 12 with an acid. In some embodiments, the acid is hydrochloric acid.

[0146] In some embodiments, the deprotection step (b) is carried out according to the following scheme: [ka]

[0147] In some embodiments, coupling step (c) is carried out in alumina-treated dioxane. In some embodiments, coupling step (c) includes contacting compound 13 with a palladium catalyst. In some embodiments, coupling step (c) includes contacting compound 13 with a base (e.g., a carbonate base such as cesium carbonate). In some embodiments, coupling step (c) is carried out in a solvent (e.g., an etheric solvent such as 1,4-dioxane). In some embodiments, coupling step (c) is carried out above room temperature (e.g., above 50°C, above 60°C, above 70°C, or above 80°C). In some embodiments, coupling step (c) is carried out at 80-90°C. In some embodiments, coupling step (c) is carried out according to the following scheme: [ka]

[0148] In some embodiments, deprotection step (d) includes contacting compound 14 with hydrogen gas. In some embodiments, the hydrogen gas is at a pressure greater than 1 atm (e.g., greater than 2 atm, greater than 3 atm, greater than 4 atm). In some embodiments, the hydrogen gas is at a pressure of about 5 atm. In some embodiments, deprotection step (d) further includes contacting compound 14 with a palladium catalyst. In some embodiments, the palladium catalyst is palladium carbon. In some embodiments, the method further includes washing a solution of compound 15 with an aqueous base (e.g., a carbonate-based basic aqueous solution such as sodium carbonate). In some embodiments, compound 15 is not isolated or purified before coupling step (e).

[0149] In some embodiments, the deprotection step (d) is carried out according to the following scheme: [ka]

[0150] In some embodiments, coupling step (e) includes contacting compound 15 and compound 2 with a coupling reagent (e.g., BOP or PyBOP). In some embodiments, coupling step (e) includes contacting compound 15 and compound 2 with a base (e.g., DIPEA). In some embodiments, coupling step (e) is carried out according to the following scheme: [ka]

[0151] In some embodiments, the method for preparing compound A further includes the step of purifying compound A by recrystallizing compound A. In some embodiments, recrystallization includes contacting compound A with one or more solvents selected from ethyl acetate, water, and diisopropylethylamine, or a mixture thereof. In some embodiments, recrystallization is carried out in a mixture of ethyl acetate and n-heptane.

[0152] Compounds and intermediates In one embodiment, the present disclosure provides a barium salt of compound 1: [ka]

[0153] In some embodiments, the barium salt has a carboxylic acid:barium ratio of 2:1. In some embodiments, the barium salt has the structure of compound 2: [ka]

[0154] In another aspect, the present disclosure relates to a compound having the structure of compound 3: [ka] or a salt thereof is provided. In some embodiments, the compound or a salt thereof has the structure of compound 3a: [ka]

[0155] In yet another embodiment, the present disclosure provides a tetramethylethylenediamine (TMEDA) salt of compound 5: [ka]

[0156] In some embodiments, the TMEDA salt has a carboxylic acid:TMEDA ratio of 2:1.

[0157] In further embodiments, the 1,4-diazabicyclo[2.2.2]octane (DABCO) salt of compound 5. In some embodiments, the DABCO salt has a carboxylic acid:DABCO ratio of 2:1.

[0158] In yet another embodiment, the present disclosure provides a hemisulfate of compound 8 (compound 8:sulfate in a 2:1 ratio): [ka]

[0159] In one embodiment, the present disclosure relates to a compound having the structure of compound 12: [ka] or provide a salt thereof.

[0160] In another aspect, the present disclosure relates to a compound having the structure of compound 13: [ka] or provide a salt thereof. [Examples]

[0161] This disclosure is further illustrated by the following examples and synthesis examples, which should not be considered to limit the scope or spirit of this disclosure to the specific procedures described herein. It should be understood that the examples are provided to illustrate specific embodiments and are not intended to imply any limitation on the scope of this disclosure. It should also be understood that various other embodiments, modifications, and equivalents can be taken, which themselves may be suggested to those skilled in the art, without departing from the spirit of this disclosure or the appended claims.

[0162] Example 1. Synthesis procedure for compound 4b-(S)-3-bromo-2-(1-methoxyethyl)pyridine.

[0163] The general synthesis procedure for compound 4a-(S)-3-bromo-2-(1-methoxyethyl)pyridine is described in detail below.

[0164] Synthesis of compound 4b-(S)-3-bromo-2-(1-methoxyethyl)pyridine. [ka] Part 1 - Synthesis of compound 4-1-(3-bromopyridine-2-yl)ethane-1-one. [ka] Toluene (2,100 L, 7V) and 3-bromopiccolinonitrile (300 kg, 1,639 mol, 1 equivalent) were added to the reactor. The resulting mixture was cooled to -20°C and maintained at -20°C. MeMgCl (3M in THF, 601 L, 1,803 mol, 1.1 equivalents) was then added. The resulting mixture was heated to 10-20°C and maintained at 10-20°C for 16 hours. At that point, HPLC analysis indicated that the reaction was complete.

[0165] The reaction mixture was added at -10 to 10°C to a pre-cooled 4M HCl aqueous solution (-10 to 0°C) (1,070 L, 2.6 equivalents), and the resulting mixture was maintained at 15 to 25°C for 30 minutes. The phases were separated, and the aqueous phase was extracted with toluene (600 L x 5, 2V x 5). The combined organic layers were washed with saturated NaHCO3 aqueous solution (100 L, 0.3V), then concentrated to approximately 200 L (0.7V) at 50 to 60°C, -0.08 MPa, to obtain crude 1-(3-bromopyridine-2-yl)ethane-1-one (compound 4a) (346 kg, area specific purity 93.7%, weight specific assay value 83.4%, yield 88%) as a brown oily substance, which was used directly in the next step. [Table 1] LRMS (ESI+) C7H7BrNO (M+H + Calculated value for ): 199.97110 Measured value: 200.0 1 H NMR (400 MHz, DMSO-d6, 25℃) δ 8.66 (dd, J = 4.6, 1.3 Hz, 1H), 8.22 (dd, J = 8.2, 1.3 Hz, 1H), 7.52 (dd, J = 8.2, 4.6 Hz, 1H), 2.61 (s, 3H).

[0166] Part 2 - Synthesis of compound 4a-(S)-1-(3-bromopyridine-2-yl)ethane-1-ol. [ka] A solution of 1-(3-bromopyridine-2-yl)ethane-1-one (compound 4) (200 kg, 999.83 mol, 1 equivalent) in potassium phosphate buffer (0.2 M, pH 6-8-7.2, 2,000 L, 10V), glucose (594 kg, 3,297 mol, 3.3 equivalents), GDH (4 kg, 2 w / w%), NADP (2 kg, 1 w / w%), KRED (2 kg, 1 w / w%), and 1-(3-bromopyridine-2-yl)ethane-1-one (compound 4) (200 L, 1V) was added to the reactor at 25-30°C. Note: If necessary, 2 M NaOH aqueous solution was used to maintain the pH at 6-5-7. The reaction mixture was maintained at 28-32°C for 6 hours. At that point, HPLC analysis indicated completion of the reaction.

[0167] Diatomaceous earth (40 kg, 20 w / w%) and MTBE (800 L, 4V) were added to the reaction mixture. The resulting mixture was filtered, and the cake was washed with MTBE (200 L, 1V). The resulting phase was separated, and the aqueous phase was extracted again with MTBE (500 L x 3, 2.5V x 3). The combined organic phase was washed with brine (100 L, 0.5V), concentrated (45~55°C, -0.08 MPa), and (S)-1-(3-bromopyridine-2-yl)ethane-1-ol (compound 4a) (204 kg, area specific purity 97.8%, weight specific assay value 89.6%, yield 90%) was obtained.

[0168] Part 3 - Alternative synthesis of compound 4a-(S)-1-(3-bromopyridine-2-yl)ethane-1-ol. [ka] Triethylamine (47 kg, 464.46 mol, 2.8 equivalents) was added to the reactor. This was cooled to 0-10°C and maintained at 0-10°C. Formic acid (19 kg, 412.82 mol, 2.5 equivalents) and RuCl(p-cymene)[(S,S)-Ts-DPEN] (0.55 kg, 864.49 mmol, 0.005 equivalents) were added. The resulting mixture was heated to 30-35°C and maintained at 30-35°C. 1-(3-bromopyridine-2-yl)ethane-1-one (compound 4) (36.7 kg, 165.12 mol, 1 equivalent) was added, and the input port was rinsed with additional triethylamine (2 kg, 19.76 mol, 0.12 equivalents). The temperature of the reaction mixture was maintained at 30-35°C for 6 hours. At that point, the HPLC analysis indicated that the reaction was complete.

[0169] The reaction mixture was concentrated (30-35°C) to remove triethylamine. Water (170 kg) and pharmaceutically acceptable HCl (310 kg) were added to the resulting mixture at 15-25°C. The phases were separated, and the aqueous phase was extracted with pharmaceutically acceptable HCl (160 kg x 2). The combined organic phase was washed with brine (158 kg x 2), dried over anhydrous Na2SO4, filtered, and the used desiccant cake was washed with pharmaceutically acceptable HCl (40 kg). The combined filtrate was cooled to 0-10°C and maintained at 0-10°C, to which 35 w / w% HCl (55 kg, 3.2 equivalents) in MeOH was added. The resulting mixture was maintained at 0-10°C for 12 hours, filtered, and the product was washed with pharmaceutically acceptable HCl (40 kg). The product was dissolved in water (66 kg) and pharmaceutically acceptable HCl (170 kg), and the resulting solution was cooled to 5-15°C and maintained at 5-15°C. A solution of NaHCO3 (33 kg) in water (170 kg) was added to this. The phases were separated, and the aqueous phase was extracted with ELISA (170 kg x 3). The combined organic phase was washed with brine (158 kg x 2), dried with anhydrous Na2SO4, filtered, and the used desiccant cake was washed with ELISA (120 kg). The filtrate was concentrated (40~45°C) to obtain (S)-1-(3-bromopyridine-2-yl)ethane-1-ol (compound 4a) (30.0 kg, area specific purity >99.9%, weight specific assay value 95%, yield 86%) as a dark brown oily substance. [Table 2] LRMS (ESI+) C7H9BrNO (M+H + Calculated value for ): 201.98675 Actual value: 202.0 1 H NMR (400 MHz, DMSO-d6, 25℃) δ 8.56 (dd, J = 4.6, 1.4 Hz, 1H), 8.02 (dd, J = 8.0, 1.4 Hz, 1H), 7.26 (dd, J = 8.0, 4.6 Hz, 1H), 5.13 - 5.04 (m, 2H), 1.37 (d, J = 6.0 Hz, 3H).

[0170] Part 4 - Synthesis of compound 4b-(S)-3-bromo-2-(1-methoxyethyl)pyridine. [ka] THF (2,025 L, 5V) and t-BuONa (231 kg, 2,404 mol, 1.2 equivalents) were added to the reactor. The resulting mixture was cooled to 0-10°C and maintained at 0-10°C. To this, a solution of (S)-1-(3-bromopyridine-2-yl)ethane-1-ol (405 kg, 2,004 mol, 1 equivalent) in THF (800 L, 2V) and MeI (340 kg, 2,395 mol, 1.2 equivalents) were added. The resulting reaction mixture was maintained at 0-10°C for 16 hours. At that point, HPLC analysis indicated that the reaction was complete.

[0171] To the reaction mixture, a 7.5 w / w% NH3 aqueous solution (520 L, 1.3V) at 0-10°C and MTBE (1,200 L, 3V) were added. The phases were separated, and the aqueous layer was extracted with MTBE (1,200 L, 3V). The combined organic phase was washed with brine (200 L, 0.5V) and concentrated (50-60°C, -0.08 MPa) to obtain crude (S)-3-bromo-2-(1-methoxyethyl)pyridine (compound 4b). Crude (S)-3-bromo-2-(1-methoxyethyl)pyridine was distilled (120°C, 600 Pa) to obtain (S)-3-bromo-2-(1-methoxyethyl)pyridine (445 kg, area specific purity 99.3%, weight specific assay value 90.2%, yield 93%) as a colorless solid (solidified after packaging). [Table 3] LRMS (ESI+) C8H 11 BrNO (M+H + Calculated value for ): 216.00240 Actual value: 216.00 1 1H NMR (400 MHz, CDCl3, 25℃) δ 8.61 (d, J = 3.2 Hz, 1H), 7.83 (q, J = 1.6, 6.8 Hz, 1H), 7.08 (q, J = 3.6, 4.8 Hz, 1H), 4. 92 (q, J = 6.4 Hz, 1H), 3.31 (s, 3H), 1.48 (d, J = 6.8 Hz, 3H).

[0172] Example 2.3,3-Dimethyldihydro-2H-pyran-2,6(3H)-dione synthesis procedure. The general synthesis procedure for 3,3-dimethyldihydro-2H-pyran-2,6(3H)-dione is described in detail below. [ka] Part 1 - Synthesis of 4,4-dimethyl-5-oxopentannitrile. [ka] 1,4-dioxane (1,552 L, 5V), hydroquinone (1.55 kg, 14.1 mol, 0.0033 equivalents), and 5 w / w% NaOH aqueous solution (341.4 kg, 426.78 mol, 0.1 equivalents) were added to the reactor. The resulting mixture was heated to 70-75°C and maintained at 70-75°C. Isobutyraldehyde (310.6 kg, 4,307.3 mol, 1 equivalent) and acrylonitrile (2) (285.7 kg, 5,384.5 mol, 1.25 equivalents) were added over 8 hours. The reaction mixture was maintained at 70-75°C for 8 hours. At that point, GC analysis indicated that the reaction was complete.

[0173] Next, the reaction mixture was cooled to 20-25°C and maintained at 20-25°C. The pH was adjusted to 5-6 with a 3.5 w / w% HCl aqueous solution (172.5 kg required) and concentrated until the organic solvent was completely evaporated (45°C, approximately 0.03 atm). The remaining residue was cooled to 20-25°C and maintained at 20-25°C. DCM (1,552 L, 5V) and water (620 L, 2V) were added to this. The phases were separated, and the organic phase was concentrated until the solvent was completely evaporated (45°C, approximately 0.03 atm) to obtain crude 4,4-dimethyl-5-oxopentannitrile as a brown oily substance (626.6 kg, area specific purity 70.8%, weight specific assay value 43.5%, yield 51%). [Table 4] LRMS (ESI+) C7H 12 NO (M+H + Calculated value for ): 126.09189 Measured value: 126.0 1 1H NMR (400 MHz, CDCl3, 25℃) δ 9.37 (s, 1H), 2.30 - 2.19 (m, 2H), 1.88 - 1.77 (m, 2H), 1.06 (s, 6H).

[0174] Part 2 - Synthesis of crude 3,3-dimethyldihydro-2H-pyran-2,6(3H)-dione. [ka] Water (1,115 kg, 5V), KH2PO4 (13.8 kg, 101.4 mol, 0.057 equivalents), DMSO (164.0 kg, 2,099.1 mol, 1.2 equivalents), and crude 4,4-dimethyl-5-oxopentannitrile (455.3 kg, weight-to-assay value 49.0%, 1,782.3 mol, 1 equivalent) were added to the reactor. The resulting mixture was cooled to 10-20°C and maintained at 10-20°C. 20 w / w% NaClO2 aqueous solution (1,185.0 kg, 2,620.5 mol, 1.5 equivalents) was added over 20 hours. The reaction mixture was then maintained at 10-20°C for 1 hour. At this point, GC analysis indicated completion of the reaction. Crude 4-cyano-2,2-dimethylbutanoic acid was obtained and used directly in the next step.

[0175] A mixture of crude 4-cyano-2,2-dimethylbutanoic acid was mixed with KOH (361.5 kg, 6,442.7 mol, 3.6 equivalents). The resulting mixture was extracted with MTBE (800 kg x 2, 4.9 V x 2). The aqueous phase was then heated to 90-100°C and maintained at 90-100°C for 15 hours. At that point, GC analysis indicated that the reaction was complete.

[0176] The reaction mixture was cooled to 15-25°C and maintained at that temperature. The pH was adjusted to 1-2 with a 30 w / w% HCl aqueous solution (1,058 kg, 4.9 equivalents). The resulting mixture was extracted with MTBE (1,058 kg x 2, 6.4V x 2). The combined organic phase was washed with a 5 w / w% NaCl aqueous solution (378 kg x 2, 1.7V x 2), concentrated to 670 L (3V) (40-45°C, approximately 0.03 atm) to obtain crude 2,2-dimethylpentanediic acid, which was used directly in the next step.

[0177] To a mixture of crude 2,2-dimethylpentanedioic acid, Ac2O (614.6 kg, 6,020.1 mol, 3.4 equivalents) was added at 40-45°C. The resulting mixture was concentrated (40-45°C, approximately 0.03 atm) to remove MTBE. The reaction mixture was heated to 80-85°C and maintained at 80-85°C for 2 hours. At this point, GC analysis indicated completion of the reaction.

[0178] Next, the reaction mixture was concentrated until the solvent completely evaporated (70-75°C, approximately 0.03 atm) to remove AcOH and Ac2O. This yielded crude 3,3-dimethyldihydro-2H-pyran-2,6(3H)-dione (390.5 kg, area specific purity 86.3%, weight specific assay value 69.3%, crude yield 107%), which was used directly in the next step.

[0179] Part 3 - Synthesis of 3,3-dimethyldihydro-2H-pyran-2,6(3H)-dione. [ka] n-heptane (574.0 kg, 1.86 V relative to crude weight) was added to the reactor. This was cooled to -10 to -5°C and maintained at -10 to -5°C. A solution of crude 3,3-dimethyldihydro-2H-pyran-2,6(3H)-dione (454.0 kg, weight-specific assay value 84.1%) in MTBE (667.2, 2 V relative to crude weight) was added to this over 10 hours. The resulting mixture was maintained at -10 to -5°C for 1.5 hours and then filtered.

[0180] The filtration cake was dissolved in MTBE (572 kg, 2V relative to the assay weight). Activated carbon (19.1 kg, 0.05 w / w%) relative to the assay weight was added to the resulting solution. This was maintained at 15-25°C for 8 hours. The resulting solution was then filtered, and the used carbon cake was washed with MTBE (18 kg, 0.05V). The filtrate was then added to pre-cooled n-heptane (-10 to -5°C) (518.4 kg, 2V relative to the assay weight) over 9 hours. The resulting mixture was maintained at -10 to -5°C for 2 hours. This was then filtered at -10 to -5°C. The product was dried for 16 hours (25-30°C, approximately 0.03 atm) to obtain 3,3-dimethyldihydro-2H-pyran-2,6(3H)-dione (212.0 kg, area specific purity 100%, weight specific assay value 98.3%, yield 55%) as an off-white solid.

[0181] Part 4 - Alternative synthesis of 3,3-dimethyldihydro-2H-pyran-2,6(3H)-dione. [ka] Ac2O (5.4 L) and 2,2-dimethylpentanedioc acid (2,573 g, weight ratio assay value 98.8% and 506 g, weight ratio assay value 90.9%, 18.74 mol, 1 equivalent) were added to the reactor. The resulting reaction mixture was heated to 110°C and maintained at 110°C for 1 hour. At that point, GC analysis indicated that the reaction was complete.

[0182] The reaction mixture was concentrated until the solvent completely evaporated (70°C, approximately 0.03 atm) to remove AcOH and Ac2O. The residue was combined with another batch (2,2-dimethylpentanedioic acid (6,610 g, weight-specific assay value 90.8%)) and distilled until the product was completely distilled (110-120°C, approximately 0.005 atm). The resulting fraction was triturated with n-heptane (35 L), filtered, and the product was dried (25°C, approximately 0.005 atm) to obtain 3,3-dimethyldihydro-2H-pyran-2,6(3H)-dione (6.66 kg, area-specific purity 99.6%, weight-specific assay value 98.56%, yield 82%) as an off-white solid. [Table 5] LRMS (ESI+) C7H 11 O3(M+H + Calculated value for ): 143.07082 Measured value: 143.0 1 1H NMR (300 MHz, CDCl3, 25℃) δ 2.82 (t, J = 7.0 Hz, 2H), 1.85 (t, J = 7.0 Hz, 2H), 1.35 (s, 6H).

[0183] Part 5 - Alternative synthesis of 2,2-dimethylpentanedioic acid. [ka] 3.3 L of 65 w / w% HNO3 aqueous solution and 500 mL of concentrated H2SO4 were added to the reactor at 25°C. The resulting mixture was heated to 70-80°C and maintained at that temperature. 4,4-dimethyl-5-oxopentannitrile (2.21 kg, weight-to-assay value 90.5%, 15.98 mol, 1 equivalent) was added in portions over 24 hours. The reaction mixture was then maintained at 70-75°C for 1 hour. At that point, GC analysis indicated that the reaction was complete.

[0184] The reaction mixture was cooled to 25°C and then placed in ice-cold water (10 kg). During this time, a solid precipitate formed. The resulting mixture was extracted with MTBE (10 L x 1, followed by 5 L x 2). The combined organic phase was washed with water (2 L x 1), then with brine (2 L x 1), dried over anhydrous Na2SO4, filtered, and then concentrated until the solvent had completely evaporated (45°C, approximately 0.03 atm). This yielded 2,2-dimethylpentanedioic acid (2.6 kg, weight-specific assay value 98.8%, yield 100%) as a white solid. [Table 6] LRMS (ESI-) C7H 11 O4(Mon + Calculated value for ): 159.06573 Measured value: 159.2 1 1H NMR (400 MHz, CDCl3, 25℃) δ 2.42 (t, J = 7.5 Hz, 2H), 1.92 (t, J = 7.5 Hz, 2H), 1.23 (s, 6H).

[0185] Example 3. Synthesis procedure for compound 5. [ka] Part 1 - TMEDA salt of compound 5 In a 3000L glass-lined reactor, THF (445L, 6V), crude 1-tert-butyl 4-ethyl 4-fluoropiperidine-1,4-dicarboxylate (74.0 kg (after assay correction), 268.8 mol, 1.0 equivalent) and MeOH (370L, 5V) were added at 20±5°C, and the mixture was stirred at 20±5°C for 15 minutes. A solution of LiOH·H2O (22.6 kg, 538.6 mol, 2.0 equivalent) in H2O (225L, 3V) was added dropwise to the reaction mixture over 30 minutes at 20±5°C (slightly exothermic), and the mixture was warmed to 45°C and stirred for 10 hours. HPLC analysis indicated that the reaction was complete. The reaction mixture was cooled to 20±5°C and diluted with H2O (740L, 10V). The mixture was sequentially washed with IPAc (740 L, 10V) and DCM (740 L x 2, 10V x 2), and then partitioned with pharmaceutically acceptable (RINKAN) (740 L, 10V). The pH of the resulting two-phase mixture was adjusted to pH 3 with 7 w / w% HCl aqueous solution (185 kg). The phases were separated, and the dilute aqueous phase at the bottom was extracted with RINKAN (740 L, 10V). The combined organic phase (1398.8 kg) was washed with 5 w / w% brine (370 L, 5V), dried with MgSO4 (84.6 kg), and filtered. The used desiccant cake was washed with RINKAN (190.6 kg).

[0186] Two batches of rich organic layers (74.0 kg (after assay correction) × 2) were combined and concentrated to 4V under reduced pressure (approximately 0.03 atm) at 45±5°C. TMEDA (28.1 kg, 241.9 mol, 0.45 equivalents) was added at 45±5°C, and the mixture was stirred at 45±5°C for 16 hours. The mixture was cooled to -10 to -15°C within 6 hours and stirred for a further 16 hours. The slurry was filtered at -10°C, and the product was washed with cold HCl (80 L, -10°C) to obtain the 1 / 2 TMEDA salt of wet compound 5. The wet product was triturated with HCl / n-heptane (1 / 1, 170 L, 2V) at 25°C for 2 hours and filtered. The product was washed with RINKAN (1 / 1, 42.5 L, 0.5 V) and dried under vacuum (approximately 0.005 atm) in an oven at 45 ± 5 °C for 12 hours (drying basis: LOD < 1.0%) to obtain the 1 / 2 TMEDA salt of compound 5 (80.0 kg, area specific purity 99.8% (TFA method), area specific purity 99.6% (H3PO4 method), weight specific assay value 98.2%, assay corrected yield 47.9%). LRMS (ESI-) C 11 H 18 FNO4(MH + Calculated value for ): 246.12 Actual value: 246.2 1 H NMR (300 MHz, d6-DMSO, 24℃) δ 3.80 (bd, 4H), 2.98 (bs, 4H), 2.78 (s, 4H), 2.42 (s, 12H), 1.07-1 / 79 (m, 4H), 1.77-1.71 (m, 4H), 1.41 (s, 18H).

[0187] Part 2 - DABCO salt of compound 5 [ka] In a 5 L round-bottom flask, THF (200 mL, 1 V) and crude 1-tert-butyl 4-ethyl 4-fluoropiperidine-1,4-dicarboxylate (164.2 g (after assay correction), 0.669 mmol, 1.0 equivalent) were added. To the mixture, a solution of NaOH (multiple) (53.52 g, 1.338 mmol, 2.0 equivalents) in water (600 mL, 3 V) was added at 25 ± 5 °C (internal temperature). The resulting mixture was stirred at 25 ± 5 °C for 2 hours. HPLC analysis indicated that the reaction was complete. The reaction mixture was diluted with water (2.00 L, 10 V) and washed twice with 2-MeTHF (1.00 L × 2, 5 V × 2). The mixture was partitioned with ELISA (1.00 L, 5 V) and the pH was adjusted to pH 2-3 with 3 N HCl aqueous solution. The phases were separated, and the dilute aqueous phase at the bottom was extracted with SiO2 (1.00 L, 5V). The combined organic layers were concentrated under reduced pressure and vacuum (approximately 0.1 MPa) at 40 ± 5°C (jacket temperature) to obtain crude compound 5 as a yellow solid (160.0 g, area specific purity 81.33%, weight specific assay value 86.8%, assay corrected yield 94.2%).

[0188] Crude compound 5 (150.0 g (130.2 g after assay correction), 0.53 mol, 1.0 equivalent)) and 2-MeTHF (750 mL, 5V) were placed in a 5 L round-bottom flask. The mixture was heated to 50 ± 5 °C, and DABCO (56.45 g, 0.53 mol, 1.0 equivalent) was added as a solution in 2-MeTHF (750 mL, 5V). The mixture was stirred at 50 ± 5 °C for 16 hours, cooled to 20-25 °C, stirred for a further 2 hours, and then filtered. The resulting cake was slurryed in THF (750 mL, 5V) at 50 ± 5 °C, isolated by filtration, and dried under vacuum at 40-50 °C to obtain compound 5DABCO salt as a white solid (121.1 g, area specific purity 99.62%, yield 63.9%). 1 1H NMR (400 MHz, D2O, 23℃) δ 3.90 (bd, 2H), 3.13 (s, 12H), 2.96 (t, 2H), 1.97-1.59 (m, 4H), 1.35 (s, 9H).

[0189] Example 4. Synthesis procedure for compound 6. [ka] 2-MeTHF (568.0 kg, 20V) and compound 7 (33.4 kg, 72.2 wt%, 289.3 mol, (after assay correction), 1.0 equivalent) were added to a 2000 L glass-lined reactor (reactor A) under positive pressure nitrogen. The mixture was stirred at 100 RPM for 10 minutes and then cooled to 0-10°C. CH2O (37 wt% aqueous solution, 163.6 kg, 2016 mol, 7.0 equivalents) was added dropwise to the cold solution at a rate of 1.6 kg / min while maintaining the internal temperature at 0-10°C. The reaction mixture was stirred at 0-10°C for 10 minutes. NaBH(OAc)3 (188.0 kg, 887 mol, 3.1 equivalents) was added to the reactor in 19 portions over 8 hours via a solid feeder while maintaining the temperature at 0-10°C. The reaction mixture was heated to 20-30°C over 3 hours, and then stirred for a further 10 hours. GC analysis showed that the area percentage of compound 7 was less than 1.0, indicating that the reaction was complete.

[0190] The reaction mixture was transferred to a 3000L glass-lined reactor (reactor B) at 0-20°C. 15% by weight of Na2CO3 (aqueous solution) (1960.0 kg, 57.8 w / w.) was added to the reactor over 90 minutes at 0-10°C with stirring (100 RPM). The two-phase mixture was heated to 10-20°C and stirred for another 20 minutes. The layers were separated, the dilute aqueous layer was returned to the 3000L reactor B, and the rich organic layer was added to the 2000L reactor A. The aqueous layer was extracted twice with 2-MeTHF (284.0 kg, 10V). The combined organic layers in reactor A were sequentially washed with 10% by weight NaCl (aqueous solution) (334.0 kg x 2), and dried with Na2SO4 (100.0 kg, 3.0 w / w) with stirring (100 RPM) at 10-20°C for 3 hours. The mixture was filtered under reduced pressure. The used drying agent was rinsed with 2-MeTHF (57.0 kg, 1.7 w / w). The filtrate was transferred to reactor A and cooled to 10-20°C. 4 Å molecular sieves (200.0 kg, 6.0 w / w) were slowly added to the solution over 3 hours at 10-20°C. The mixture was heated to 20-30°C and maintained at 20-30°C under slight N2 pressure for 12 hours with only periodic stirring at 1 minute per hour (30 RPM). The mixture was filtered, and the used molecular sieves were washed twice with 2-MeTHF (28.0 kg, 2V). The filtrate was distributed into eight 200 L HDPE drums, with 140 kg of filtrate in each drum. 4 Å molecular sieves (10.0 kg, approximately 7 wt% relative to the 2-MeTHF solution) were slowly added to each drum. The filtrate was kept at 20-35°C for 72 hours (12-120 hours). The KF assay of compound 7c in 2-MeTHF solution met the criterion of less than 1000 ppm.

[0191] A solution of compound 7c in 2 MeTHF (568.0 kg, gravimetric assay value 2.68%, 1.0 equivalent) was introduced into a 1000 L stainless steel reactor under vacuum and nitrogen pressure. Note that an in-line filter was used to isolate molecular sieves contained in the feed drum. The solution was cooled to -80 to -75°C with stirring (100 RPM). LiHMDS (190.8 kg, 1 M in THF, 1.6 equivalents) was added dropwise while maintaining the temperature at -80 to -65°C (approximately 1.5 kg / min). The reaction mixture was further stirred at -80 to -65°C under nitrogen for 6 hours. CO2 (gas) (60 kg) was added to the reaction mixture at a rate of 80 to 100 g / min at -65 to -45°C until the reaction mixture was saturated. Saturation was determined when a large amount of gas was observed in the tail gas by a bubbler. The reaction mixture was stirred for a further 8 hours at -62°C to -45°C. HPLC assay of the reaction indicated that the reaction was complete, with an area % of compound 7c being less than 5.0. The reaction mixture was gradually warmed to 20-30°C over 10-20 hours to release dissolved CO2 gas. The reaction mixture was transferred to a 2000L glass-lined reactor and concentrated under reduced pressure of 10-20 bar and at 40-50°C to a target volume of 50-60L. n-heptane (45.0 kg, 66 L) was added to the reactor, and the mixture was concentrated again to 50-60L. The isolation process was repeated two more times with n-heptane (2 × 45.0, 66 L) to a final volume of 50-60L. siRNA (107.3 kg, 120 L) was added to the reactor. The mixture was stirred at 20-30°C for 3 hours to dissolve the solid. n-heptane (246.0 kg, 360 L) was added to the reactor. The slurry was further stirred at 20-30°C for 3 hours and then filtered. The resulting solid was washed twice with n-heptane (2 × 45.0 kg, 66 L), dried under reduced pressure (10-15 mbar) at 40-45°C for 20 hours, and 24.7 kg of compound 7a (lithium salt) (HPLC purity 89% and qNMR gravimetric assay value 53.8%) was obtained as a white solid in 61.3% yield.

[0192] AcOH (630.0 kg, 5.24 w / w) was added to a 3000 L glass-lined reactor. Compound 7a (120.0 kg) was added in 10 portions (10-15 kg / portion) over 90 minutes while maintaining the temperature at 20-25°C. The mixture was stirred at 20-25°C for 6 hours to obtain a clear solution. siRNA (2160.0 kg, 18 w / w) was added to the solution over 30 minutes. The mixture was stirred at 20-25°C for 12 hours. The resulting solid was isolated by centrifugation and washed twice with siRNA (2 × 270.0 kg, 2.25 w / w) to obtain 116.2 kg of the wet product, the AcOH salt of compound 7b.

[0193] The wet product (116.2 kg) and ethyl acetate (2160.0 kg, 18 w / w) were placed in a 5000 L glass-lined reactor. To the resulting suspension, 4 M HCl in ethyl acetate (240 kg, 2 w / w) was added over 25 minutes (approximately 10 kg / min) at 20-25°C. The resulting suspension was stirred at 20-25°C for 12 hours. The resulting solid was isolated by centrifugation, washed twice with ethyl acetate (2 × 130.0 kg, 1.1 w / w), and dried under reduced pressure at 35-40°C for 40 hours to obtain 63.5 kg of compound 6 (HPLC purity 96.2%, residual AcOH of 1757 ppm by HS-GC, and gravimetric assay value of 97.7% by qNMR) as a white solid with a corrected yield of 85.3%. LRMS (ESI+) C8H 1h NO2(M+H + Calculated value for ): 156.09 Measured value: 156.1 1 1H NMR (400 MHz, d6-DMSO) δ 2.78 (s, 6H), 1.70 (s, 6H).

[0194] Example 5. Synthesis procedure for compound 11b. [ka] Part 1 - Synthesis of Compound 9-(S)-5-(2-(1-methoxyethyl)pyridine-3-yl)-2,2-dimethyl-5-oxopentanoic acid [ka] In a 3,000 L Hastelloy-lined reactor, THF (1,200 L, 10.0 times volume, 70 L / min) and (S)-3-bromo-2-(1-methoxyethyl)pyridine (compound 4b, 120 kg, 20 kg / min) were added under N2 conditions at 15-25°C. The resulting mixture was cooled to -15--10°C.

[0195] i-PrMgCl.LiCl (448 L, 3.74 times the volume, 1.05 equivalents) was added dropwise to the reactor at -25 to -15°C. The reaction mixture was stirred at -15 to -5°C under N2 for 1 hour.

[0196] A solution of 3,3-dimethyldihydro-2H-pyran-2,6(3H)-dione (82.9 kg, 0.69 times the weight, 1.05 equivalents) in THF (360 L, 3.00 times the volume) was added to the reactor under N2 conditions at -15 to -5°C. The reaction mixture was stirred at -8 to -12°C for 12 hours.

[0197] The reaction mixture was quenched at 0-10°C under N2 by adding water (360 L, 3.00x volume), and then concentrated to 500-600 L. A mixture of AcOH (60.0 L, 0.50x volume) and water (1,200 L, 10.0x volume) was added to the concentrated mixture. The two-phase mixture was extracted twice with ELISA (1,200 L, 10.0x volume). The combined organic phase was concentrated to 400-500 L.

[0198] n-heptane (1,205 L, 3.00x volume) was added to the concentrated solution, and the resulting mixture was concentrated to approximately 400-500 L. This unit operation was repeated two more times. A 1:1 solution of MTBE:n-heptane (1,205 L, 3.00x volume) was added to the concentrated solution. The resulting slurry was stirred under N2 at 15-20°C for 16 hours. The solid was isolated by filtration and dried under N2 at 35-40°C for 12-24 hours to obtain compound 9 as an off-white solid (isolation yield 57.5%, weight ratio assay value 99.2%, 100% ee, purity 99.5%). 1 H NMR (400 MHz, DMSO-d6, 25℃) δ 12.20 (s, 1H), 8.60 (d, J=3.2 Hz, 1H), 7.89 (dd, J=15.6, 1.2 Hz, 1H) 7.39 (dd, J=7.6, 4.8 Hz, 1H), 4.55 (q, J=6.4Hz, 1H), 3.11 (s, 3H), 2.80 (dd, J=16.0, 8.0 Hz, 2H), 1.80 (dd, J=16.0, 8.0 Hz, 2H), 1.42 (d, J=6.4 Hz, 3H), 1.12 (s, 6H).

[0199] Part 2 - Synthesis of Compound 8-(S)-3-(5-bromo-2-(2-(1-methoxyethyl)pyridine-3-yl)-1H-indole-3-yl)-2,2-dimethylpropanoic acid [ka] In a 5,000L glass-lined reactor, water (1,565L, 5.00 times volume), H2SO4 (440kg, 1.40 times weight, 4.00 equivalents), compound 9 (313kg, 1 equivalent), and compound 10 (250kg, 0.80 times weight, 1.00 equivalent) were added under N2 conditions at 10-20°C. The mixture was heated to 95-100°C and stirred for 18 hours.

[0200] The reaction mixture was cooled to 50-60°C and neutralized to pH 4-5 by adding 1,800 L of 20 wt% NaOH aqueous solution under N2. Compound 8 was precipitated by further adjusting the pH to 6.2-6.8 using approximately 65 L of K2HPO4 aqueous solution. The solid was isolated by centrifugation, rinsed with water (1,290 L, 5.00 times volume), and dried under N2 at 45-50°C for 24 hours to obtain compound 8 (456 kg, assay-corrected yield 80.6%, area purity 85.0%) as a brown solid.

[0201] Analysis data for compound 8: 1 H NMR (400 MHz, DMSO-d6, 25℃) δ 12.14 (bs, 1 H), 11.42 (s, 1 H), 8.71 (dd, J=4.4, 1.2 Hz, 1H), , 7.45 (dd, J=8.0, 4.8 Hz, 1H), 7.31 (d, J=8.8 Hz, 1H) 7.21 (d, J = 8.4 Hz, 1 H), 4.18 (q, J=6.4 Hz, 1 H), 2.93 - 2.77 (m, 5 H), 1.36 (d, J = 6.0 Hz, 3 H), 0.88 (d, J = 6.4 Hz, 6 H).

[0202] Part 3: Synthesis of Compound 16-ethyl(S)-3-(5-bromo-1-ethyl-2-(2-(1-methoxyethyl)pyridine-3-yl)-1H-indole-3-yl)-2,2-dimethylpropanoate [ka] In a 5,000 L glass-lined reactor, DMF (973 L, 7.00 times volume) and compound 8 (139 kg, 1 equivalent) were added under N2 conditions at 10-20°C. The mixture was stirred at ambient temperature to obtain a clear solution, which was then cooled to 0-5°C.

[0203] NaOH (32.2 kg, 0.24 times the weight, 2.50 equivalents) and EtI (126 kg, 0.91 times the weight, 2.50 equivalents) were added to the mixture. The reaction mixture was heated to 15-20°C and stirred for 6 hours.

[0204] The reaction mixture was quenched with water (1,390 L, 10.0x volume) at 0–20°C. The resulting mixture was extracted twice with MTBE (5–10x volume). The combined organic layers were concentrated at 35–45°C. The concentrated mixture was diluted with THF (278 L, 2.00x volume) and further concentrated under reduced pressure at 35–45°C to approximately 2v (approximately 150 L). The previous unit procedure was repeated until the MTBE content in the THF solution was less than 1 w / w%. The THF solution of the resulting compound 16 was used directly in the next step as a 1:1 mixture of diastereomers (385 kg, HPLC weight ratio assay value 33.5%, isolation yield 96.3%, assay value: 129 kg).

[0205] Part 4 - Synthesis of Compound 11-(S)-3-(5-bromo-1-ethyl-2-(2-(1-methoxyethyl)pyridine-3-yl)-1H-indole-3-yl)-2,2-dimethylpropan-1-ol [ka] A THF solution of compound 16 (661.8 kg, assay value of compound 16: 205.3 kg) was added to a 1,000 L glass-lined reactor at 15-20°C under N2. LiBH4 (2 M in THF, 1.20 equivalents) was added to the mixture at 50-60°C, and the mixture was then stirred at 50-60°C under N2 for 12 hours.

[0206] The reaction mixture was quenched in 0.50 M HCl (aqueous solution) (1,455 L, 7.08 times volume). The pH of the mixture was adjusted to pH 4-5 with 0.50 M HCl (aqueous solution). The resulting mixture was extracted with HCl (1,810 L, 8.80 times volume). The phases were separated. The organic layer was washed with brine (743 L, 3.61 times volume) and concentrated to 1300 L to obtain HCl solutions of compounds 11a and 11b as a 1:1 mixture of diastereomers (1,484 kg of HCl solution, area purity 93.12%, assay corrected yield 97.6%, 11a+11b assay value: 183 kg).

[0207] Part 5 - Isolation of compound 11b from a mixture of compounds 11a and 11b [ka] The ethyl phosphate solutions of compounds 11a and 11b were concentrated to 1.2–1.5V in a 5,000L glass-lined reactor, to which xylene (2.29 times the volume) was added. The mixture was stirred at 90–100°C for 2 hours to evaporate the residual ethyl phosphate, and then heated to 135–140°C for 4 hours to equilibrate the diastereomer mixture to a ratio of less than 1:1.6 (11a:11b). The reaction mixture was then cooled to 20–25°C, concentrated to 1.2–1.5V, and diluted with IPA (3.87 times the volume) at 40–45°C. The solution was further cooled to 20–25°C, diluted with additional IPA (4.77 times the volume), and treated with HCl solution in IPA (5 mol / L, 1.32 times the volume). The resulting suspension was stirred at 20–25°C for 16–24 hours and then filtered. The resulting wet cake was dissolved in IPA (5.00 times its volume) with stirring at 70-75°C for 4 hours, and then at 20-25°C for 10 hours. The solid was isolated by filtration and dried under N2 at 35-40°C for 24 hours to obtain the first product of compound 11b (388 kg, area purity 99.0%, chiral purity 99.7%, yield 46%) as a pale yellow solid.

[0208] The product-rich filtrates were combined and concentrated until almost dry. The resulting brown oily substance was purified by silica gel chromatography (column height: 250 mm, diameter: 100 mm, 100-200 mesh silica gel, n-heptane / ethyl acetate = 5 / 1-0 / 1) to obtain a fraction rich in the product of the mixture of compounds 11a and 11b. This mixture was subjected to the equilibration process again to obtain compound 11b (151 kg, area purity 98.7%, chiral purity 99.7%, yield 15%) as a pale yellow solid. 1 H NMR (400 MHz, DMSO-d6, 25℃) δ 8.93 (d, J=4.0 Hz, 1H), 8.35 (d, J=7.6 Hz, 1H), 7.89-7.92 (m, 2H), 7.52 (d, J=8.8 Hz, 1H), 7.32 (dd, J=8.4, 1.6 Hz, 1H), 4.02-4.15 (m, 2H), 3.75-3.85 (m, 1H), 2.93-3.04 (m, 5H), 2.67 (d, J=14Hz, 1H), 2.12 (d, J=14Hz, 1H), 1.44 (d, J=6 Hz, 3H), 1.11 (t, J=6.8 Hz, 3H), 0.64 (s, 3H), 0.60 (s, 3H).

[0209] Example 6. Alternative synthesis of compound 11b This example describes an alternative synthesis of compound 11b. This method prepares compound 9 using an acid chloride derivative of 3,3-dimethyldihydro-2H-pyran-2,6(3H)-dione. An additional method via compound 22 improves the initial ratio of the desired atropisomer compound 11b to the undesirable compound 11a. This method may have the advantage of using more readily available and cost-effective substrates.

[0210] The advantage of using stepwise alkylation is that indole alkylation exhibits higher diastereoselectivity, allowing the desired compound 11b to be obtained in a ratio greater than 5:1 compared to the undesirable compound 11a.

[0211] [ka] Preparation of compound 20 500 g of 2,2-dimethylglutaric anhydride, methanol (8V), and sulfuric acid (0.13 equivalents) were added to the reaction vessel. The mixture was stirred at 55°C for 24 hours. The solvent was distilled under vacuum at 50°C. The residue was partitioned with water (3V) and MTBE (7V). The organic layer was washed with water and brine and distilled under vacuum to obtain diester compound 18 as an oil. The crude diester, methanol (8V), and potassium hydroxide (1.2 equivalents) were stirred at room temperature for 14 hours, and then heated under reflux for a further 2 hours. The mixture was cooled to room temperature, concentrated under reduced pressure, acidified with 1 M HCl (aqueous solution), and partitioned with brine and MTBE. The organic phase was concentrated to obtain carboxylic acid compound 19 as a solid. Compound 19, toluene (5V), and DMF (1 wt%) were added to the reactor. Thionyl chloride (1.5 equivalents) was slowly added while maintaining the temperature at 0-10°C. The reaction mixture was stirred at room temperature for 14 hours. The solvent was removed by vacuum distillation at 50-55°C, and the product was isolated by high-vacuum distillation to obtain compound 20 as an oily substance.

[0212] Preparation of compound 21 [ka] Step 1a: THF (100 mL, 1.0 vol) was added to reactor R1 under nitrogen protection. 1.3 M i-PrMgCl·LiClTHF solution (374 mL, 1.05 equivalents) was added to the mixture at 20-30°C. The temperature was adjusted to -10-0°C. Compound 4b (100 g, 1.0 equivalent) in THF (200 mL, 2 vols) was added dropwise to the reaction mixture at -10-0°C. The mixture was stirred at -10-0°C for 2 hours, and then sampled for IPC (HPLC purity: compound 4b-2 95.0 A% and compound 4b 0.2 A%).

[0213] Step 1b: 2-MeTHF (300 mL, 3 volumes) and ZnCl2 (72.3 g, 1.15 equivalents) were added to reactor R2 under nitrogen protection. The temperature was adjusted to -10 to 0°C. The reaction mixture from R1 was added dropwise to R2 at -10 to 0°C over 1 hour. THF (50 mL, 0.5 volumes), CuCl (4.6 g, 0.1 equivalents), and LiCl (3.9 g, 0.2 equivalents) were added to reactor R3 and stirred at 20 to 30°C for 1 hour. The reaction mixture in R3 was added dropwise to R2 at -10 to 0°C. Compound 20 (107 g, 1.2 equivalents) was added dropwise to R2 at -10 to 0°C. The mixture was stirred at -10 to 0°C for 16 hours, and then sampled for IPC (HPLC purity: Compound 21 92.7A% and Compound 4b-2 0.6A%). The reaction mixture was heated to 25-30°C. Toluene (500 mL, 5 volumes), AcOH (83.3 g, 3.0 equivalents), and H2O (300 mL, 3.0 volumes) were added to the reaction mixture and stirred for 0.5 hours. The organic phase was separated, and the aqueous phase was extracted with toluene (300 mL, 3 volumes). The combined organic phase was washed with 10% ammonia hydroxide (300 mL x 2, 3 volumes x 2). The organic phase was concentrated to 1-1.5 volumes under vacuum. 158 g of compound 21 was obtained as a brown oily substance (HPLC purity 96.2% and uncorrected yield 89%).

[0214] Step 1c: Add water (5 vol) to the crude product and stir for 15 minutes. Cool the reaction to 5±5°C. Slowly add lithium hydroxide (2 equivalents) at 5±5°C. Raise the temperature to 25±5°C and stir for 14-16 hours. Monitor the progress of the reaction by HPLC (limit: compound 21: NMT 1.0%). After the reaction is complete, wash the reaction with MTBE (2 × 5 vol) and adjust the pH to 5-6 with 50% acetic acid solution (1 vol) (a solid precipitate will form). Stir the resulting mixture for 3-4 hours, filter the solid, and wash with water (5 vol), followed by heptane (5 vol). Dry the product under vacuum at 50°C. Purity: NLT: 95%, Yield range: 65-70%.

[0215] Preparation of the hemisulfate of compound 8 [ka] This procedure reduces bromination impurities and enables efficient flow chemistry for recycling the compound 11a / compound 11b mixture (see below).

[0216] H2O (50 mL, 2.5 vol) and concentrated H2SO4 (13.4 g, 1.0 equivalent) were added to reactor R1 under nitrogen protection. Compound 21 (20.0 g, 1.0 equivalent) and compound 10 (16.0 g, 1.05 equivalent) were added to the mixture at 20-30°C. The temperature was adjusted to 90-100°C. The mixture was stirred at 90-100°C for 48 hours, and then sampled for IPC (HPLC purity: compound 8 84.2 A%, compound 21 0.2 A%, and compound 21a 1.1 A%). The mixture was cooled to 60-65°C, and H2O (110 mL, 5.5 vol) was added to the mixture at 60-65°C. Then, NaOH (5.5 g, 2.0 equivalent) was added to the mixture at 60-65°C, and the mixture was stirred at 60-65°C for 2 hours. The mixture was cooled to 20-25°C and stirred for 2 hours. The mixture was filtered, and the filtered cake was rinsed with H2O (40 mL, 2.0 vol). The wet filtered cake was dried at 50-55°C under reduced pressure (-0.95 MPa) for 14 hours. 26.9 g of compound 8 1 / 2H2SO4 was obtained as a pale yellow solid (HPLC purity 96.2% and corrected yield 78%).

[0217] Alternative experimental procedure for preparing the hemisulfate of compound 8 [ka] Sulfuric acid (238 kg, 2.0 equivalents) was added dropwise to water (807.7 L) under N2 under a temperature of 20°C ± 20°C. Compound 9 (340 kg, after assay correction) and compound 10 (299.18 kg, 1.1 equivalents) were added at 20 ± 10°C. The reaction mixture was stirred at 70-75°C for at least 30 minutes, and then further stirred at 95 ± 10°C for 32 hours. HPLC monitoring of the reaction indicated that the detection amount of compound 9 was less than 1%, indicating that the reaction was complete. The reaction mixture was cooled to 60-65°C. Water (1871.5 kg) and 30% by weight NaOH (aqueous solution) (298.5 kg, 1.9 equivalents) were added, and the mixture was stirred for at least 5 hours. The slurry was cooled to 25 ± 5°C over 4 hours, further stirred at 25 ± 5°C for 2 hours, and then filtered. The obtained solid was washed with water (1020 kg) to obtain a wet cake of 538.95 kg. The wet cake was re-slurried in a mixture of water (1619 kg) and H2SO4 (85.04 kg) at 80-85°C for 5 hours, and further stirred at 25-30°C for 16 hours. The solid was isolated by filtration, washed with water (1020 L), and dried under vacuum at 50±5°C for 36 hours to obtain 446 kg of compound 8-1 / 2H2SO4 as a yellow solid hemisulfate.

[0218] Preparation of compound 22 [ka] 1 / 2 H₂SO₄ (2.0 kg, 1.0 equivalent) of compound 8 and EtOH (7V) were added to reactor R1 under nitrogen protection at 20-25°C. DMF (1.0 w / w%) was added to the reactor to form a suspension. SOCl₂ (1.0 equivalent) was added dropwise to the suspension over 1 hour with stirring at 0-10°C to obtain a homogeneous clear solution. The reaction mixture was heated to an internal temperature of 60-65°C and stirred for 16 hours. IPC analysis indicated that the reaction was complete (compound 8 < 2.5%; sample diluted with ethanol). The reaction mixture was cooled to 20-25°C, and the pH was adjusted to approximately 7.0 by adding saturated NaHCO₃ aqueous solution (approximately 10V). After neutralization was complete, the reaction mixture was stirred further at 20-25°C for 1 hour. The mixture was filtered, and the filter cake was washed with water (2V). Next, the wet cake was slurryed in water (7V) for 5 hours. The slurry was then filtered, and the cake was washed with water (2V). The cake was further dried under high vacuum at a temperature below 50°C to obtain compound 22 (1,756g; purity 98.9%; yield 96%; KF moisture 0.02%).

[0219] Alternatively, the carboxylic acid may be activated as a mixed anhydride before reduction in the next step (for example, using isobutyl chloroformate), or the carboxylic acid may be directly reduced to a primary alcohol in the next step.

[0220] Preparation of compounds 11a and 11b [ka] Compound 22 (100.0 g, 1.0 equivalent), EtOH (500 mL, 5.0 volume), and CaCl2 (24.2 g, 1.0 equivalent) were added to the reactor. The mixture was stirred at 25-30°C for 30 minutes. NaBH4 (20.6 g, 2.5 equivalents) was added in batches to the mixture at 25-30°C. The mixture was stirred at 25-30°C for 16 hours, and then sampled for IPC (HPLC purity: Compound 23 97.2 A% and Compound 22 0.92 A%). The reaction mixture was adjusted to pH 1-2 with 3M HCl (approx. 2.4V) at 20-30°C (internal temperature). The mixture was stirred at 20-30°C for 30 minutes. The reaction mixture was adjusted to pH 4.5-5.0 with 30% NaOH aqueous solution (approx. 2.5V) at 20-30°C (internal temperature). The mixture was stirred at 20-30°C for 30 minutes. 500 mL of water (5.0 vol) was added to the mixture at 25-30°C. The mixture was stirred at 20-30°C for 14 hours. The mixture was filtered, and the filter cake was rinsed with 200 mL of water (2.0 vol). The wet filter cake was dried at 55-60°C under reduced pressure (-0.95 MPa) for 14 hours. 89 g of compound 23 was obtained as an off-white solid (HPLC purity 97.6% and uncorrected yield 95%).

[0221] 270 mL (9.0 vol.), 1,4-dioxane (90 mL (3.0 vol.), and compound 23 (30.0 g (1.0 equivalent)) were added to the reactor. KOH (7.3 g (1.8 equivalent) was added to the mixture in batches at 15-30°C (internal temperature). Diethyl sulfate (DES) (17.7 g (1.6 equivalent)) was added dropwise to the mixture at 25-30°C (IT). The mixture was stirred at 25-30°C for 16 hours, and then sampled for IPC [HPLC purity: compound 11b was 96.4 A% (compound 11b / compound 11a ratio: 7.05) and compound 23 was not detected]. The mixture was stirred at 20-30°C for 30 minutes. Water (90 mL (3.0 vol.)) was added to the mixture at 25-30°C, stirred for 30 minutes, and the organic phase was separated. 2-MeTHF (60 mL, 2.0 vol) was added to the aqueous phase at 20-30°C, stirred for 30 minutes, and the aqueous phase was separated. The combined organic phase was concentrated and replaced with THF (300 mL, 10.0 vol). 6M HCl (10.8 mL, 0.9 equivalents) was added dropwise to the mixture at 20-30°C. The mixture was stirred at 20-30°C for 13 hours. The mixture was filtered, and the filter cake was rinsed with THF (60 mL, 2.0 vol). The wet filter cake was dried at 50-55°C under reduced pressure (-0.95 MPa) for 14 hours. 26.0 g of compound 11b-HCl was obtained as a pale yellow solid (HPLC purity 97.9% and uncorrected yield 74%).

[0222] Alternative synthesis using compound 24 intermediate [ka] 2-MeTHF (150 mL, 5.0 vol), 1,4-dioxane (150 mL, 5.0 vol), and compound 22 (30.0 g, 1.0 equivalent) were added to the reactor. KOH (6.6 g, 1.8 equivalents) was added in batches to the mixture at 20-30°C. The mixture was cooled to -5-0°C, and diethyl sulfate (DES) (16.1 g, 1.6 equivalents) was added dropwise to the mixture at -5-0°C. The mixture was stirred at -5-5°C for 24 hours, and then sampled for IPC [HPLC purity: compound 24 99.0 A% and compound 22 0.7 A% (ratio of desired atropisomer / undesired atropisomer 5.3:1)]. HOAc (7.1 g, 1.8 equivalents) was added dropwise to the reactor and stirred for 0.5 hours. The reaction mixture was then heated to 20-30°C, and 10% NaCl aqueous solution (90 mL, 3.0 vol) was added to the mixture at 20-30°C. The mixture was stirred for 30 minutes. The aqueous phase was separated. The organic phase was washed with 10% by weight NaCl aqueous solution (90 mL, 3.0 vol), concentrated under reduced pressure at 30-40°C, and replaced with EtOH (150 mL, 5.0 vol) to obtain compound 24 as a solution (HPLC purity 97.0% and assay corrected yield 97%).

[0223] EtOH solution of compound 24 (142 g, equivalent to 30.9 g of pure compound 24, 1.0 equivalent) was added to the reactor at 20-30°C. CaCl2 (7.1 g, 1.0 equivalent) was added to the mixture at 25-30°C. The mixture was stirred at 25-30°C for 1 hour. NaBH4 (6.0 g, 2.5 equivalents) was added in batches at 25-30°C. The mixture was stirred at 25-30°C for 24 hours, and then sampled for IPC (HPLC purity: compound 11 98.2A% and compound 24 0.3A%). 3M aqueous HCl (90 mL, 3.0 vol) was added dropwise to adjust the pH to 1-2 at 25-30°C, and the mixture was stirred for 0.5 hours. H2O (150 mL, 5.0 vol) was added, and the mixture was stirred for 0.5 hours. A 30 wt% NaOH aqueous solution (14.5 mL, 0.46 vol) was added dropwise at 25-30°C to adjust the pH to 4.5-5.0, and the mixture was stirred for 0.5 hours. AcONa (3.1 g, 0.6 equivalents) was added in batches at 25-30°C. The mixture was heated to 60-65°C and stirred for 2 hours. The mixture was cooled to 25-30°C and stirred for 2 hours. The mixture was filtered, and the filter cake was rinsed with H2O (45 mL, 1.5 vol). The wet filter cake was dried under reduced pressure at 50-55°C for 14 hours. 26.2 g of a mixture of compounds 11a and 11b was obtained as an off-white solid (HPLC purity 99.3% (including undesirable atropisomers: 16.6 A%) and uncorrected yield 93%). A mixture of compounds 11a and 11b (26.2 g) was placed in a reactor, and THF (260 mL, 10 vols) was added to the reactor. 6M HCl (9.5 mL, 0.9 equivalents) was added dropwise to the mixture at 20-30°C. The mixture was stirred at 20-30°C for 13 hours. The mixture was filtered, and the filter cake was rinsed with THF (60 mL, 2.0 vols). The wet filter cake was dried under reduced pressure at 50-55°C for 14 hours. 21.3 g of compound 11b was obtained as a pale yellow solid (HPLC purity 99.5% (excluding undesirable products) and uncorrected yield 75%).

[0224] Example 7. Separation of compounds 11a and 11b in a flow. A mixture of compounds 11a and 11b (free base) and THF (10V) were added to the reactor. The mixture was stirred at 25±5°C for 2 hours, and then filtered through diatomaceous earth (2.5 wt%). The filtrate was pumped to a flow reactor at 220°C with a residence time of 240 seconds, and then rapidly cooled to 0°C with a residence time of 120 seconds. The effluent was recovered into the reactor as a mixture of atropisomers in a ratio greater than 1.58:1. Seed crystals of compound 11b HCl (0.05 wt%) were added to the reactor. HCl in IPA (0.25 equivalents, approximately 0.15V) was added to the reactor over a period of 5 hours or more while maintaining the temperature at 25±5°C. The mixture was further stirred at 25±5°C for 4 hours. Additional HCl (0.25 equivalents, approximately 0.15V) in IPA was added to the reactor over a period of 5 hours or more while maintaining a temperature of 25±5°C. The mixture was further stirred at 25±5°C for 4 hours. The solid was isolated by centrifugation and washed with THF (0.5V) to obtain compound 11b HCl. The isolated solid was slurryed in IPA (8V) at 60-70°C for 5 hours or more. The slurry was cooled to 10-20°C over 5 hours or more, stirred for a further 2 hours, and filtered. The isolated solid was washed with IPA (2×2.5V) and dried under vacuum at 40±5°C.

[0225] The filtrate obtained from centrifugation was passed through a chloride ion exchange column to obtain a mixture of compounds 11a / 11b (free base). This mixture can be isomerized in the same manner as described above.

[0226] Figure 1 shows a schematic diagram of the flow process used to separate compound 11b from compound 11b.

[0227] Example 8. Synthesis procedure for compound 3a. Part 1 - Synthesis of Compound 3h-tert-butyl(R)-2-formylmorpholine-4-carboxylate [ka] In a 3000L glass-lined reactor (A), tert-butyl(R)-2-(hydroxymethyl)morpholine-4-carboxylate (compound 3i) (104 kg, 478.7 mol, 1.0 equivalent) and butyl (1032 kg, 11 v) were added, followed by the addition of a solution of NaHCO3 (120.6 kg, 1436.1 mol, 3.0 equivalents) and TEMPO (0.75 kg, 4.787 mol, 0.01 equivalent) in butyl (94 kg, 1 v). The resulting mixture was purged three times with N2 and cooled to -15 to -10°C.

[0228] TCCA (100.1 kg, 430.8 mol, 0.9 equivalents) and siRNA (938 kg, 10V) were added to a 2000 L reactor (B). The mixture was stirred until a clear solution was obtained. The resulting solution was purged three times with N2 and cooled to -10 to -5°C. The mixture was then added to a 3000 L glass-lined reactor (A) while maintaining the temperature at -10 to 0°C. The resulting mixture was stirred at -5 to 0°C for 1 hour. At that point, GC monitoring indicated that the reaction was complete.

[0229] The reaction mixture was quenched by adding an aqueous solution of Na2S2O3 (prepared by dissolving 520 kg of Na2S2O3 in 832 kg of water) at 0-15°C and stirred at below 15°C for 30 minutes. The phases were separated, and the abundant organic phase was washed with water. The combined aqueous phase was extracted with pharmaceutically acceptable phosphate (703 kg × 4, 7.5 v × 4). The combined organic matter was then washed with 20 wt% brine (520 kg × 2, 5 v × 2). The organic phase was then concentrated to 4-5 v under reduced pressure (-0.85 to -0.9 MPa) at 15-35°C to obtain an pharmaceutically acceptable phosphate solution of compound 3h. 1 H NMR (400 MHz, CDCl3, 25℃) δ 9.69 (s, 1H), 3.98-3.65 (m, 5H), 3.16-3.03 (m, 2H), 1.52 (s, 9H). [Table 7]

[0230] Part 2 - Synthesis of compound 3g-tert-butyl(S,Z)-2-(2-(((benzyloxy)carbonyl)amino)-3-methoxy-3-oxopropane-1-en-1-yl)morpholine-4-carboxylate [ka] In a 3000 L reactor, a solution of 3h of compound HCl (containing 763 kg, 675 kg of HCl and 82.4 kg, 382.8 mol, 1.0 equivalent of 51), methyl 2-(((benzyloxy)carbonyl)amino)-2-(dimethoxyphosphoryl)acetate (139.4 kg, 421.1 mol, 1.1 equivalents), and HCl (437 kg, 15V) were added. The mixture was purged three times with N2 and cooled to -5 to 0°C. Then, tetramethylguanidine (110.2 kg, 957 mol, 2.5 equivalents) was added dropwise at -5 to 5°C, and the reaction mixture was stirred for 0.5 hours. GC monitoring indicated that the reaction was complete.

[0231] The reaction mixture was placed in a 5000L reactor containing H2O (824 kg, 10v) and cooled to -5 to 5°C. The resulting mixture was stirred for 0.5 hours. The organic phase was separated, and the aqueous phase was extracted with RINKAN (400 kg x 2, 5v x 2). The combined organic phase was sequentially washed with 5 wt% citric acid in 20 wt% brine (400 kg x 2, 5v x 2), 5 wt% aqueous NaHCO3 solution (400 kg x 3, 5v x 3), and 20 wt% brine (400 kg x 1, 5v x 1), respectively. The resulting organic layer was concentrated to approximately 1.5 to 2v under reduced pressure at 40 to 45°C. THF (371 kg, 5v) was added to the residue, and the mixture was further concentrated to 1.5 to 2v under reduced pressure at 40 to 45°C. The previous unit procedure was repeated to obtain 3 g of the compound as a THF solution (HPLC assay corrected yield 91% and 100% ee (by chiral HPLC)). 1H NMR (400 MHz, CDCl3, 25℃) δ 7.33-7.27 (m, 5H), 7.03 (s, 1H), 6.05 (d, J = 4.0 Hz, 1H), 5.10(dd, J = 20, 12 Hz, 2H), 4.20-3.80 (m, 7H), 3.50-3.40 (m, 1H), 2.97-2.80 (m, 2H), 1.42 (s, 9H). [Table 8] [Table 9] [Table 10]

[0232] Part 3 - Synthesis of compound 3b salt using compound 3f - (S,Z)-2-(((benzyloxy)carbonyl)amino)-3-(4-(tert-butoxycarbonyl)morpholine-2-yl)acrylic acid, (R)-1-phenylethane-1-amine salt [ka] In a 2000L reactor, 3g of compound in a THF solution (204.5kg; 106.3kg, 252.9mol, containing 52 and 109L of THF in 1.0 equivalent units) and THF (380kg-532L, 5v) were added. The mixture was stirred at ambient temperature to obtain a clear solution, and then cooled to 0-10°C. An aqueous solution of LiOH monohydrate (15kg, 354.1mol, 1.4 equivalent units) in water (266L, 2.5v) was added to the cold solution below 10°C over 3.5 hours. After the addition was complete, the mixture was warmed to 10-15°C and stirred for a further 1 hour at 10-15°C. HPLC monitoring of the reaction indicated that the reaction was complete.

[0233] 0.1 M aqueous HCl solution (106 L, 1 v) was added to the crude reaction mixture. The reaction mixture was concentrated to 400 L under reduced pressure at 35-40°C. Water (532 L, 5 v) was added to the mixture, and the mixture was extracted twice with MTBE (390 kg x 2, 5 v x 2). The aqueous phase was then cooled to 0-10°C, and 1 M aqueous HCl solution (307 kg) was added dropwise until the pH was 2-3. The resulting aqueous phase was further extracted twice with MTBE (550 kg x 1, 7 v x 1, 390 kg x 1, 5 v x 1). The combined organic phase was washed with brine (500 kg x 2, 5 v x 2), heated to 20-30°C, and treated with Na2SO4 (100 kg, 1 w) and activated carbon (21 kg, 20 wt%). The mixture was stirred at 20-30°C for 1 hour and filtered. The used solid was rinsed twice with MTBE (150kg x 2, 1.5V x 2).

[0234] Compound 3f((R)-(+)-1-phenylethylamine) (30.6 kg, 252.8 mol, 1.0 equivalent) was added dropwise to the filtrate solution over 30 minutes at 10-25°C. The mixture was stirred at 10-25°C for 18 hours. The resulting solid was isolated by filtration and washed twice with MTBE (150 kg × 2, 1.5 v × 2). The wet cake was dried under reduced pressure at 40-45°C to obtain 108 kg of compound 3b salt as a white solid (assay-corrected yield 77.3% and 100% ee). 1 H NMR (400 MHz, CDCl3, 25℃) δ 8.01 (brs, 2H), 7.37-7.27 (m, 10H), 5.77 (d, J = 8.0 Hz, 1H), 5.08(dd, J = 20, 12 Hz, 2H), 4.24-4.20 (m, 2H), 4.09-3.80 (m, 3H), 3.53-3.26 (m, 1H), 2.97-2.80 (m, 1H), 2.70-2.60 (m, 1H), 1.52-1.47 (m, 12H). [Table 11] [Table 12] [Table 13]

[0235] Part 4a - Synthesis of Compound 3c-(S)-2-(((benzyloxy)carbonyl)amino)-3-((S)-4-(tert-butoxycarbonyl)morpholine-2-yl)propanoic acid [ka] Compound 3b salt (100 kg, 95.37 wt% qNMR), MTBE (740 kg, 10v), and water (500 kg, 5v) were added to a 3000 L reactor. The mixture was stirred for 10 minutes and then cooled to 0-5°C. The pH of the mixture was adjusted to pH 2 using 1 M HCl (aqueous solution) (containing 270 kg of water and 36 kg of 30% HCl aqueous solution) at a temperature below 10°C. The mixture was stirred for 10 minutes. The phases were separated. The isolated aqueous phase was further adjusted to pH 3.5 using 1 M HCl (aqueous solution) and extracted with MTBE (370 kg, 5v). The combined organic layers were sequentially washed with HCl (0.05 M, containing 100 kg of water and 0.5 kg of 30% HCl, 1v) and brine (200 kg, 2v x 3). The washed organic phase was heated to 15-25°C and treated with Na2SO4 (100 kg, 1 wt) and activated carbon (10 kg, 10 wt%). The mixture was stirred at 15-25°C for 1 hour and filtered through a diatomaceous earth pad (20 kg, 0.2 wt). The used solid was rinsed twice with MTBE (150 kg x 2, 1.5 v x 2). The combined organic filtrate was further filtered through an organic membrane and concentrated under reduced pressure at 35-40°C to approximately 2 v (200 L). MeOH (400 kg, 5 v) was added to the resulting residue, and the solution was concentrated again under reduced pressure at 35-40°C to approximately 2 v (approximately 200 L). The procedure was repeated two more times to obtain compound 3b as a MeOH solution (301.5 kg, 25.5 wt% (by HPLC assay), containing 77 kg of 52a).

[0236] The MeOH solution of compound 3b was transferred to a 1000 L pressure reactor and diluted with MeOH (160 kg, 2.4 v, total 6 v). The mixture was purged three times with N2 and further degassed by bubbling with N2 at a rate of 8.5 L / min at 15–25°C for 2 hours. The solution of (S,S)-Et-DuPhos-Rh (207.5 g, 0.287 mol, 0.152 mol%) in the degassed MeOH (1.8 L) prepared in a glove box was added to the pressure reactor under reduced pressure. The reactor was then purged three times with N2, followed by three times with H2. The reaction solution was stirred at 35–40°C for 5 hours while maintaining the H2 pressure at 4–10 atm. HPLC monitoring of the reaction indicated that the reaction was complete. The pressure in the reactor was released and the reactor was purged with N2.

[0237] A saturated aqueous solution of NaHCO3 (200 kg, 2.5 v, containing 180 kg of water and 20 kg of NaHCO3) was added to the reaction mixture. The reaction mixture was concentrated to 3-4 v under reduced pressure at 45-50°C, and then diluted with water (200 kg, 2.5 v). The pH was adjusted with an aqueous solution of Na2CO3 (42 kg of water and 18 kg of Na2CO3). The mixture was stirred for 30 minutes. The phases were separated. The aqueous phase was washed with MTBE (185 kg x 3, 2.5 v x 3). The washed aqueous phase was re-partitioned with MTBE (370 kg, 5 v), and the pH was adjusted to pH 2 with 1 M HCl (aqueous solution) (450 kg of water and 61.3 kg of 30% HCl) at a temperature below 10°C. The phases were separated, and the pH of the aqueous phase was further adjusted to 2-4 with 1 M HCl (aqueous solution). Next, the acidic aqueous phase was extracted with MTBE (370 kg x 2, 5v x 2). The combined organic layers were washed with brine (230 kg x 2, 3v x 2) and treated with Na2SO4 (100 kg, 1w) and activated carbon (3.9 kg, 5 wt%) at 15-25°C for 1 hour. The mixture was stirred and then filtered through a diatomaceous earth pad (15 kg, 0.2w). The used desiccant and carbon were washed with MTBE (150 kg x 2, 2v x 2). The combined filtrate was concentrated under reduced pressure at 35-45°C to approximately 2v (approximately 150 L), and then DCM (500 kg, 5v) was added to the residue. The mixture was further concentrated under reduced pressure at 35-45°C to approximately 2v (approximately 150 L). The previous unit procedure was repeated twice to obtain compound 3c as a pale yellow DCM solution with a corrected yield of 96% from the compound 3b salt (221.2 kg, 32.1% by weight (by HPLC assay), containing 71 kg of 57). 1 H NMR (400 MHz, CDCl3, 25℃) δ 8.68 (brs, 1H), 7.36-7.28 (m, 5H), 6.05 (app s, 1H), 5.13(dd, J = 20, 12 Hz, 2H), 4.59 (app s, 1H), 3.86-3.45 (m, 5H), 3.00-2.80 (m, 1H), 2.60-2.50 (m, 1H), 2.00-1.90 (m, 2H), 1.47 (s, 9H). [Table 14] [Table 15-1] [Table 15-2] [Table 15-3] [Table 16-1] [Table 16-2]

[0238] Part 4b - Alternative Synthesis of Compound 3c [ka] Alternatively, compound 3b may be directly hydrogenated as a salt without first generating the free base of compound 3b.

[0239] In this procedure, compound 3b salt (150 kg) and MeOH (420 kg, 3.5 v) were added to the reactor. The reactor and its contents were purged three times with N2. The solution was cooled to -5 to 5°C and slowly treated with MsOH (26.78 kg, 0.98 equivalents) while maintaining the temperature at -5 to 5°C. The solution was warmed to 10 to 20°C and transferred to a hydrogenation reactor. After purging the reactor and its contents three times with N2, it was treated with a solution of (S,S)-Et-DuPhos-Rh (308.2 g, 0.15 mol%) in MeOH (1.5 L). The reaction mixture was purged three times with N2, followed by three times with hydrogen gas. The reaction mixture was stirred at 35 to 40°C under 10 atm of H2 for 5 hours. HPLC monitoring of the reaction showed that the amount of compound 3b detected was 0.3% or less, indicating that the reaction was complete. The reaction mixture was cooled to 15-25°C, purged with N2, transferred to a reactor, diluted with 5% by weight NaHCO3 (600 kg), and concentrated to 5-6V at 45-50°C under reduced pressure (-0.0955 MPa to 0.0968 MPa). The concentrate was diluted with water (150 kg, 1 V), adjusted to pH 9-10 using 20% ​​by weight Na2CO3 aqueous solution (180 kg), and partitioned with MTBE (222 kg, 2 V). The abundant aqueous layer was washed twice with MTBE (2 × 222 kg), partitioned with MTBE (390 kg, 3.5 V), and adjusted to pH 1-3 using 1.5 M HCl (669 kg) at 0-10°C. The phases were separated, and the aqueous layer was further extracted twice with MTBE (2 × 333 kg). The combined organic layers were washed twice with 0.05 M HCl aqueous solution (301.5 kg) and 20% by weight brine (2 × 300 kg). The organic layers were treated with Na₂SO₄ (150 kg, 1% by weight) and activated carbon (7.6 kg, 5% by weight), stirred at 15-25°C for 1 hour, and filtered through diatomaceous earth (7.5 kg, 0.05% by weight). The filter aid was washed three times with MTBE (3 × 112 kg). The combined filtrate was solvent-exchanged under reduced pressure at 35-45°C using a total of 7V dichloromethane to obtain 422.3 g (25% by weight) of a pale yellow solution of compound 3c.

[0240] Part 5 - Synthesis of Compound 3e-tert-butyl(S)-2-((S)-2-(((benzyloxy)carbonyl)amino)-3-((S)-3-(methoxycarbonyl)tetrahydropyridazine-1(2H)-yl)-3-oxopropyl)morpholine-4-carboxylate [ka] A DCM solution of compound 3d (172 kg, 26.4 wt%, net weight: 45.4 kg, 1.2 equivalents) and DCM (940 kg, 10 v) were added to a 2000 L glass-lined reactor. The reactor was then purged twice with N2 and cooled to 0-5°C. N-methylmorpholine (31.6 kg, 1.8 equivalents) was added to the mixture over 10 minutes at 0-5°C, followed by a DCM solution of compound 3c (221 kg, 32.1 wt%, net weight: 70.9 kg, 1.0 equivalent) at 0-5°C. The mixture was stirred at 0-5°C for 10 minutes. HOBt (470 g, 0.02 equivalents) and EDCI (46.6 kg, 1.4 equivalents) were added to the mixture at 0-5°C. The reaction mixture was stirred at 0-5°C for 2 hours. HPLC-based reaction monitoring indicated that the reaction was complete.

[0241] The crude reaction mixture was sequentially washed three times with water (710 kg x 3, 10V x 3) and once with brine (910 kg, 10V). The organic solution was partially concentrated to approximately 200 L under reduced pressure, and then MeOH (168 kg) was added. The mixture was further concentrated to approximately 200 L under reduced pressure. The previous unit operation was repeated one more time to obtain compound 3e as a MeOH solution (319 kg solution), which was used in the next step without further purification. 1 H NMR (400 MHz, CDCl3, 25℃) N / A. [Table 17] [Table 18]

[0242] Part 6 - Synthesis of Compound 3a-(S)-1-((S)-2-(((benzyloxy)carbonyl)amino)-3-((S)-4-(tert-butoxycarbonyl)morpholine-2-yl)propanoyl)hexahydropyridazine-3-carboxylic acid [ka] Compound 3e in MeOH (319 kg, 29.1% by weight, net weight: 92.9 kg, 1.0 equivalent) and MeOH (514 kg, 7v) were added to a 2000 L glass-lined reactor. The reactor was purged twice with N2 and cooled to 3-4°C. In a 1000 L glass-lined reactor, an aqueous LiOH solution was prepared by dissolving 11 kg of LiOH·H2O (1.5 equivalents) in 650 kg of water (7v). The aqueous base was added to the initial mixture over 2 hours at 0-5°C. The mixture was stirred for 2 hours at 0-5°C. HPLC monitoring indicated that the reaction was complete.

[0243] The reaction mixture was neutralized to pH 6-7 by using a 1M aqueous HCl solution at 0-15°C, and concentrated under reduced pressure to remove most of the organic solvent. After concentration, MTBE (688 kg, 10V) was added to the residue, and then the pH of the mixture was adjusted to pH 3-4 using a 1M aqueous HCl solution at or below 15°C. After pH adjustment, solid NaCl (28 kg, 0.3 wt) was added, and the mixture was stirred for 1 hour. The phases were separated. The organic phase was washed with a 20 wt% aqueous NaCl solution (930 kg, 10V), treated with seed crystals of compound 3a (1.4 kg, 1.5 wt%), and stirred at 15-25°C for 20 hours. Then, n-heptane (635 kg, 10V) was added to the resulting slurry over 5 hours at 15-25°C. The slurry was cooled to 0-5°C and stirred for a further 2 hours. The solid was isolated by filtration, washed with 1:1 (v / v) MTBE / n-heptane (130 kg x 2), and dried at 45-55°C under high vacuum (4-7 mbar) for 18 hours to obtain compound 3a as a white solid (84 kg, 98.9% gravimetric assay value by qNMR, 90.3% assay correction yield in two steps from compound 3c). 1 H NMR (400 MHz, DMSO-d6, 25℃) δ 12.73 (brs, 1H), 7.38-7.31 (m, 5H), 7.12 (d, J = 12 Hz, 1H), 5.07-4.95 (m, 4H), 4.05 (d, J = 12 Hz, 1H), 3.74-3.65 (m, 3H), 3.35-3.20 (m, 3H, overlaps with residual water peak in DMSO-d6), 2.90-2.75 (m, 2H), 2.50 (app brs, 1H), 1.85-1.75 (m, 1H), 1.54-1.52 (m, 2H), 1.50-1.45 (m, 3H), 1.39 (s, 9H). [Table 19] [Table 20] [Table 21]

[0244] Example 9. Synthesis procedure for compound 2. Compound 17 can be prepared, for example, as described in WO2021 / 091982.

[0245] Part 1 - Synthesis of Compound 2 (Barium Salt) [ka] MTBE (270.35 kg, 8V) and water (451.00 kg, 10V) were added to the reactor at 25±5°C. Compound 17 maleate (45.65 kg, 1.0 equivalent) and Na2CO3 (18.9 kg, 2.1 equivalents (2.08-2.12 equivalents)) were added sequentially at 25±5°C. Additional MTBE (66.65 kg, 2V) was added to the reactor at 25±5°C. The mixture was stirred at 25±5°C until all solids were dissolved. The phases were separated. The isolated dilute aqueous layer was extracted once with MTBE (166.40 kg, 5V). The combined organic layers were washed with 9 wt% NaCl (aqueous solution) (225.0 L, 5V) and concentrated under reduced pressure to 2-4V. MTBE was replaced with THF (3 × 200 0.6 kg (5V)) and the solution was distilled under reduced pressure to approximately 160 L (2-4V). GC analysis of the solution showed that the MTBE level was less than 1 area percent, indicating that the standard was met.

[0246] THF (109.15 kg, 2.5V) and water (13.00 kg, 0.3V) were added to the reactor, followed by Ba(OH)2·8H2O (13.95 kg, 0.52 equivalents (0.515~0.525 equivalents)). The reaction mixture was stirred at 42±5°C for 30 hours. The reaction mixture was cooled to 25±5°C and assayed by HPLC. The result of compound 17 at 2.4 area% did not meet the criterion of 2.0 area% or less. Ba(OH)2·8H2O (0.36 kg, 0.01 equivalent) was added to the reactor at 25±5°C. The temperature was adjusted, and the reaction mixture was stirred at 42±5°C for 3 hours, then cooled to 25±5°C. HPLC analysis of the reaction mixture showed that compound 17 met the criterion of 2.0 area% or less. The reaction mixture was concentrated to 140 L (2-4V), then azeotropically dried with THF (7 × 200.25 kg, 5V) to a final volume of 100 L (2-4V). The reaction product met the KF endpoint of 0.5% by weight or less. n-heptane (460.60 kg, 15V) was added to the second reactor. The THF solution of compound 2 was added dropwise to the n-heptane. The resulting slurry was stirred for 30 minutes, then concentrated to 295 L (6-7V). Additional n-heptane (91.50 kg, 3V) was added to the reactor. GC analysis of the reaction product showed that the criterion of 5% area of ​​THF or less was met. The temperature was adjusted to 25±5°C, and the reaction mixture was stirred for 5 hours. The solid was isolated by centrifugation, washed once with n-heptane (62.05 kg, 2V), and dried at 40±5°C to obtain 39.96 kg (85.91 mol) of an off-white solid. 1 H NMR (400 MHz, d6-DMSO, 25℃) δ 4.36 (dd, J=10.4, 2.4 Hz, 1H), 4.08-4.22 (m, 2H), 3.40-3.51 (m, 1H), 3.01-3.07 (m, 2H), 2.76 (d, J=4.8 Hz, 3H), 2.21 (s, 6H), 1.84-2.21 (m, 4H), 1.36 (s, 6H), 0.94-0.98 (m, 3H), 0.71-0.77 (m, 3H).

[0247] Part 2 - Alternative Synthesis of Compound 2 (Barium Salt) [ka] MTBE (7.0V, 246.55 kg), water (10V, 476.5 kg), maleate of compound 17 (1.0 equivalent, 47.56 kg), and Na2CO3 (2.1 equivalents, 20.15 kg) were added to the reactor at 20±5°C. Additional MTBE (1.0V, 35.25 kg) was added to the same reactor as a rinse agent. The mixture was stirred under nitrogen until all solids were dissolved. The phases were separated. The dilute aqueous layer of the isolated lower layer was extracted with MTBE (5V, 176.35 kg) and the layers were separated. The combined organic layers were washed with 9 wt% NaCl (aqueous solution) (5V, 265.9 kg) and concentrated to 2-4V under reduced pressure. MTBE was replaced with THF (3 × approximately 214 kg (5V)) and the mixture was concentrated to 2-4V under reduced pressure distillation. THF (3.0V, 112.20kg), water (0.3V, 14.25kg), and Ba(OH)2.8H2O (0.52 equivalents, 13.80kg) were added to the reactor. The reaction mixture was stirred at 42±5℃ for 36 hours, cooled to 25±5℃, and analyzed by HPLC. The criterion of compound 17 being 1.0 area% or less was not met. Ba(OH)2.8H2O (0.05 equivalents, 1501.7kg) was added to the reactor at 25±5℃. The reaction mixture was stirred at 42±5℃ for 18 hours, cooled to 25±5℃, and analyzed by HPLC. The reactants met the criterion of compound 17 being 1.0 area% or less. 1M HCl (aqueous solution) (0.08 equivalents, 7.21kg) was added dropwise to the reaction mixture at 20±5℃. The reaction mixture was further stirred at 20±5°C for 30 minutes. THF was replaced with toluene (2 × 20⁴ kg (5V)) and the mixture was further concentrated to 2–4V. Analysis of the mixture showed that it met the KF standard of less than 0.5%. n-heptane (322.85 kg, 10V) was added dropwise at 20±5°C and the mixture was concentrated to 6–7V. Additional n-heptane (100.25 kg, 3V) was added to the reactor. The reaction mixture was further stirred at 20±5°C for 5 hours. The solid was isolated by filtration, washed twice with n-heptane (33 kg, 1V), and dried at 45±10°C for 28 hours to obtain 40.76 kg of white solid (yield 93.0% and area purity 98.5%). 1 H NMR (400 MHz, d6-DMSO, 23℃) δ 4.37 (d, J=9.2 Hz, 1H), 4.08-4.22 (m, 2H), 3.44-3.50 (m, 1H), 3.00-3.10 (m, 2H), 2.69-2.76 (m, 3H), 1.84-2.30 (m, 4H), 2.21 (s, 6H), 1.36 (d, J=4.0 Hz, 6H), 0.94-0.98 (m, 3H), 0.71-0.77 (m, 3H).

[0248] Part 3 - Synthesis of Compound 2 (Free Acid) The barium salt of compound 2 can be converted to a free acid form or various amine salts. The free acid and / or amine salts may offer the possibility of improving the purity and / or reactivity of compound 2.

[0249] To prepare the free acid of compound 2, 1.0 equivalent of compound 2 1 Add 2Ba and 4V water to the reactor at 20±5°C. Then add 1M H2SO4 aqueous solution (0.53 equivalents) to the reactor. Stir the resulting mixture at 20±5°C for 2 hours, then filter through Celite to remove BaSO4. Concentrate the filtrate to 4-5V. Perform 8 solvent changes with toluene (5.0V). Concentrate the mixture to dryness to obtain a viscous oily substance. Add the oily substance and 10V MTBE to the reactor, stir at 20±5°C for 6 hours, and filter.

[0250] The free acid of compound 2 functions in coupling with compound 15, as described in Example 8 below. Other salts of compound 2 can be formed using maleic acid, tartaric acid, and chiralamine (non-racemic) bases including cinconidine, kinin, and (S)-cyclohexylethylamine. These may offer advantages in terms of isolation, purification, stability, or coupling.

[0251] Example 10. Synthesis procedure for compound A. Part 1 - Compound 12 - (1 2Synthesis of M)-tert-butyl(S)-2-((S)-2-(((benzyloxy)carbonyl)amino)-3-((S)-3((3-(5-bromo-1-ethyl-2-(2-((S)-1-methoxyethyl)pyridine-3-yl)-1H-indole-3-yl)-2,2-dimethylpropoxy)carbonyl)tetrahydropyridazine-1(2H)-yl)-3-oxopropyl)morpholine-4-carboxylate [ka] 8.60 kg (1 equivalent) of the hydrochloride salt of compound 11a and dimethyl (79 kg, 10V) were added to a 500 L glass-lined reactor. The mixture was cooled under nitrogen to 10-20°C and treated with an aqueous K2CO3 solution (46 kg, 6.5% by weight, 1.1 equivalents). The mixture was stirred at 10-20°C for 0.5 hours. The phases were separated, and the organic phase was washed twice with water (46 kg x 2) and once with brine (46 kg, 25% by weight). The resulting organic layer was concentrated to obtain compound 11a as an dimethyl solution, which was used directly in step 1.

[0252] Compound 3a (10.6 kg, 1.15 equivalents), HOBt (2.4 kg, 1.0 equivalent), DMAP (1.1 kg, 0.5 equivalents), and RINKAN (112 kg) were added to a concentrated solution of compound 11a in RINKAN. The mixture was stirred under nitrogen at 15-25°C, and DIPEA (9.2 kg, 4.0 equivalents) was added in portions over 3 hours. EDCI (5.3 kg, 1.5 equivalents) was added in portions over 8 hours at 15-25°C with stirring. HPLC monitoring of the reaction indicated that the reaction was complete.

[0253] The crude reaction mixture was sequentially washed with 10% by weight citric acid aqueous solution (70 kg x 2), 5% by weight NaHCO3 aqueous solution (70 kg x 2), and brine (58 kg). The crude organic solution was concentrated under reduced pressure at 40°C using NMT to obtain compound 12 as an RINKAN solution (102 kg, 19.0% by weight), which was used in the next step without further purification. LRMS (ESI+) C 48 H 64 BrN6O9(M+H + Calculated value for ): 947.38 Actual values: 946.1; 948.1.

[0254] Part 2 - Compound 13 - (1 2 Synthesis of M)-3-(5-bromo-1-ethyl-2-(2-((S)-1-methoxyethyl)pyridine-3-yl)-1H-indole-3-yl)-2,2-dimethylpropyl(S)-1-((S)-2-(((benzyloxy)carbonyl)amino)-3-((S)-morpholine-2-yl)propanoyl)hexahydropyridazine-3-carboxylate [ka] A solution of compound 12 siRNA (102 kg, 19% by weight, 1.0 equivalent) was added to a 500 L glass-lined reactor and cooled under nitrogen to -10 to 0°C. A solution of HCl in siRNA (100 kg, 4 M) was added to the reactor over 2 hours under nitrogen at -10 to 0°C. The mixture was stirred under nitrogen at -10 to 0°C for 10 to 16 hours. Reaction monitoring indicated that the reaction was complete.

[0255] HCl (37 kg) was added to the reaction mixture, and excess HCl was removed by sparging the mixture with nitrogen at -10 to 0°C for 2 to 4 hours. The slurry was filtered, and the wet cake was washed with HCl (35 kg). The crude solid was slurryed with HCl (167 kg) and cooled under nitrogen to -10 to 10°C. While maintaining the temperature at -10 to 10°C, aqueous NaHCO3 solution (168 kg, 7 wt%) was slowly added. The mixture was heated to 15 to 25°C and stirred for 2 hours. The phases were separated, and the organic layers were sequentially washed with aqueous NaHCO3 solution (168 kg, 7 wt%) and brine (168 kg, 25 wt%). The crude organic solution was concentrated under reduced pressure at NMT 40°C to obtain a solution of the crude product in HCl. Next, the compound 13 was purified by crystallization using a mixture of ammonium and cyclohexane to obtain compound 13 as a solid (12.35 kg, 85.2% by weight, 80% assay-corrected yield in 2 steps). C 43 H 56 BrN6O7(M+H + Calculated value for ): 847.33 Actual measured values: 846.0, 848.0.

[0256] Part 3a - Compound 14-(1 2 M)-benzyl((2 2 S,6 3 S,4S)-1 1 -ethyl-1 2 -(2-((S)-1-methoxyethyl)pyridine-3-yl)-10,10-dimethyl-5,7-dioxo-6 1 ,6 2 ,6 3 ,6 4 ,6 5 ,6 6 -Hexahydro-1 1 Synthesis of H-8-oxa-2(4,2)-morpholina-1(5,3)-indona-6(1,3)-pyridazineacycloundecafan-4-yl)carbamate [ka] Compound 13 (10 kg, 1.0 equivalent), Cs2CO3 (11.5 kg, 3.0 equivalent), water (1.00 kg), and 1,4-dioxane (383 kg, 35 v) were added to a 1000 L reactor. The mixture was stirred for 30 minutes, and then degassed by bubbling nitrogen over it while stirring for 4 hours. P(t-Bu)3HBF4 (0.26 kg, 0.08 equivalent) and P(t-Bu)3PdG3 (0.51 kg, 0.08 equivalent) were added to the reactor, and the reaction mixture was further degassed by bubbling nitrogen over it for 2 hours. The reaction mixture was stirred at 80-88°C for 4-7 hours. HPLC monitoring of the reaction indicated that the reaction was complete.

[0257] The crude reaction mixture was cooled to 15-35°C, after which toluene (42 kg) and water (48 kg) were added. The mixture was stirred at 15-25°C for 60 minutes. The phases were separated. The organic phase was washed with brine (53 kg, 25 wt%) and concentrated under reduced pressure at NMT 50°C to obtain a concentrated solution (65 kg). The concentrated solution was added to water (55 kg) with stirring. The resulting slurry was stirred at 15-25°C for 4 hours and filtered. The solid was washed with water and recrystallized from a mixture of MeOH and water to obtain compound 14 as a solid (3.35 kg, assay-corrected yield 40%). 1 H NMR (400 MHz, d6-DMSO, 25℃) δ 8.75 (d, J=4 Hz, 1H), 7.81 (d, J=4 Hz, 1H), 7.42 (d, J=8 Hz, 1H), 7.29-7.35 (m, 5H), 7.18 (d, J=8 Hz, 1H), 6.99-7.05 (m, 2H), 7.50 (dd, J=8, 4 Hz, 1 H). 5.30 (bd, J=4 Hz, 2 H), 4.99 (q, J=12 Hz, 2 H), 4.10-4.30 (m, 3 H), 3.82-3.95 (m, 2H), 3.58-3.76 (m, 5H), 3.43 (d, J=12 Hz, 1H), 3.22 (d, J=12 Hz, 1H), 3.05 (s, 3H), 2.65-2.85 (m, 4H), 1.99 (d, J=4 Hz, 2H), 1.81 (d, J=Hz, 2H), 1.50-1.70 (m, 2H), 1.40 (d, J=4 Hz, 3H), 0.97 (bs, 3H), 0.68 (bs, 3H), 0.57 (bs, 3H).

[0258] Part 3b - Alternative methods for synthesizing compound 14 The following alternative synthesis of compound 14 allows for the use of lower-cost, more readily available materials and provides a more robust process.

[0259] In a 1000 mL three-necked round-bottom flask, crushed Cs2CO3 (23.06 g, 3.0 equivalents), anisole (300 mL, 15V), bis(tri-t-butylphosphine)palladium (0) (1.2 g, 2.36 mmol, 0.1 equivalent), and water (1.3 mL, 3.0 equivalents) were added under an inert atmosphere. The reaction mixture was sparged with inert gas from below the liquid surface for 10-15 minutes and heated to 85°C (84-87°C). Compound 13 (20 g) was added as a solution in anisole (10V) over 4-5 hours under an inert atmosphere. After another hour, HPLC monitoring indicated that the reaction was complete. The reaction mixture was cooled to 50°C and filtered through a Solka-Floc® cellulose filter aid to remove insoluble solids. The reactor and filter aid were washed with anisole (2V).

[0260] A portion of the filtrate (9.33V = 1 / 3 of the total volume), water (112 mL, 5.6V), and seed crystal (1 wt%) were added to the reactor to adjust the anisole-to-water ratio to 62.5:37.5. The slurry was aged at room temperature for at least 12 hours with moderate to high-speed stirring. To the resulting slurry, filtrate (4.6V = 1 / 6 of the original total volume) and water (2.8V) were added simultaneously at the same rate over 1 hour. The mixture was concentrated to 15V at 50°C under reduced pressure. Filtrate (4.6V = 1 / 6 of the original total volume) and water (2.8V) were added simultaneously, and the concentration was repeated three more times. The resulting concentrated slurry was aged at 50°C for at least 12 hours and further concentrated to 10V at 50°C under reduced pressure. Additional water was added as needed to adjust the anisole / water ratio to 8:2. The slurry was further concentrated to 7V at 50°C under reduced pressure. If necessary, additional water was added to achieve an anisole / water ratio of 9:1. The slurry was aged at 50°C for 3 hours, cooled to 10°C over 6 hours, and aged at 10°C for at least 12 hours. The solid was isolated by filtration, washed 7 times with heptane (1V), and dried under reduced pressure at 40°C.

[0261] Part 4 - Compound 15 - (1 2 M)-(2 2 S,6 3 S,4S)-4-amino-1 1 -ethyl-1 2 -(2-((S)-1-methoxyethyl)pyridine-3-yl)-10,10-dimethyl-6 1 ,6 2 ,6 3 ,6 4 ,6 5 ,6 6 -Hexahydro-1 1 Synthesis of H-8-oxa-2(4,2)-morpholina-1(5,3)-indola-6(1,3)-pyridazineacycloundecafane-5,7-dione [ka] Compound 14 (2.26 kg, 1.0 equivalent), 10% Pd / C (0.32 kg), THF (10.0 kg, 5 v), and MeOH (4.5 kg, 2.5 v) were added to a 50 L pressure reactor. The mixture was stirred at 5 atm of H2 and 30-40°C. During the reaction, the atmosphere was changed several times by aeration and filling with fresh H2.

[0262] After the reaction was completed by monitoring with HPLC, the atmosphere was changed to N2, and the reaction mixture was filtered through a diatomaceous earth pad. The used filter aid was washed with a mixture of THF and MeOH. The combined filtrate was then concentrated under reduced pressure at NMT 40°C and diluted with RINKAN (186 kg). The mixture was further concentrated under reduced pressure at NMT 30°C to approximately 67-146 L. The addition of RINKAN and concentration were repeated two more times to remove THF and MeOH. The resulting crude product solution in RINKAN was stirred with SiliaMetS Thiol® (0.732 kg) at 15-25°C for 15 hours. After filtration, the crude product in RINKAN was concentrated under reduced pressure at NMT 30°C, and subsequently, the mixture of RINKAN and n-heptane was crystallized to obtain compound 15 as a solid. HRMS (ESI+) C 35 H 49 Calculated value for N6O5(M+H): 633.37 Measured value: 633.1 1H NMR (400 MHz, d6-DMSO, 24℃) δ 8.74 (d, J=4 Hz, 1H), 7.78 (d, J=8 Hz, 1H), 7.50 (dd, J=4, 4 Hz, 1H), 7.43 (d, J=8 Hz, 1H), 7.04 (d, J=8 Hz, 1H), 7.00 (s, 1H), 5.14 (bd, J=12 Hz, 1H), 4.51 (bt, J=4 Hz, 1H), 4.36 (bd, J=12 Hz, 1H), 4.25-4.16 (m, 2H), 4.06-3.93 (m, 3H), 3.74-3.56 (m, 5H), 3.45 (d, J=12 Hz, 1H), 3.25 (d, J=12 Hz, 1H), 3.14 (s, 3H), 2.78-2.65 (m, 4H), 2.03 (bd, J=12 Hz, 1H), 1.99 (s, 1H), 1.84-1.51 (m, 5H), 1.39 (d, J=4 Hz, 3H), 1.18 (t, J=8Hz, 1H), 0.90-0.84 (m, 3H), 0.72 (bs, 3H), 0.43 (bs, 3H).

[0263] Part 5 - Compound A - (1 2 M)-1-(4-(dimethylamino)-4-methylpenta-2-inoyl)-N-((2S)-1-(((2 2 S,6 3 S,4S)-1 1 -Ethyl-12-(2-((S)-1-methoxyethyl)pyridine-3-yl)-10,10-dimethyl-5,7-dioxo-6 1 ,6 2 ,6 3 ,6 4 ,6 5 ,6 6 -Hexahydro-1 1 Synthesis of H-8-oxa-2(4,2)-morpholina-1(5,3)-indona-6(1,3)-pyridazineacycloundecafan-4-yl)amino)-3-methyl-1-oxobutan-2-yl)-4-fluoro-N-methylpiperidine-4-carboxamide [ka] Compound 15 (1.91 kg, 1.0 equivalent) and DMF (13.9 kg) were added to a 50 L glass reactor. The mixture was stirred at 20-30°C until all solids were dissolved. Compound 2 (1.70 kg, 1.2 equivalents) and DMF (3.8 kg) were added. The mixture was stirred at 20-30°C until all solids were dissolved. DIPEA (2.20 kg, 5.50 equivalents) was added at 20-30°C, and the mixture was cooled to -20 to -10°C while stirring. Ethyl cyanoglycylate-2-oxime (Oxyma) (0.48 kg, 1.1 equivalents) was added to the reactor, and the reaction mixture was stirred at -20 to -10°C for 30 minutes. PyBOP was added to the reactor as a DMF solution (1.89 kg dissolved in 3.62 kg of DMF, 1.2 equivalents) within 1 hour at -20 to -10°C. The reaction mixture was stirred at -20 to -10°C for 1 to 3 hours. HPLC monitoring of the reaction indicated that the reaction was complete.

[0264] The crude reaction mixture was diluted with HCl (3.6 kg) and partitioned with a mixture of HCl (65 kg) and brine (25 wt%, 132 kg). The two-phase mixture was stirred at 20-30°C for 1 hour and filtered through a diatomaceous earth pad. The reactor and the wet cake of the used filter aid were rinsed with HCl (11 kg). After allowing the combined filtrate to stand for 1 hour, the phases were separated. The organic layer was washed once with brine (25 wt%, 90 kg x 2). HCl (0.6 M aqueous solution, 71 kg) was added to the isolated organic layer at 5-20°C. The two-phase mixture was stirred at 10-20°C for 1 hour. The phases were separated, and the dilute organic layer was extracted with HCl (0.6 M aqueous solution, 30 kg). The combined rich aqueous phase was washed three times with HCl (34 kg x 3). SiO(34 kg) was added to the washed aqueous phase, and the pH was adjusted to 9-10 by adding a 30% Na2CO3 aqueous solution at 10-20°C. The mixture was stirred at 10-20°C for 1 hour, and the phases were separated. The dilute aqueous phase was extracted with SiO(34 kg), and the combined rich organic phase was washed twice with brine (25% by weight, 90 kg x 2). The resulting organic layer was then washed with brine with acetic acid solution (prepared by dissolving 0.23 kg of glacial acetic acid and 8 kg of 25% by weight brine in 115 kg of water) (39 kg x 2), brine with Na2CO3 solution (prepared by dissolving 1.3 kg of Na2CO3 and 8 kg of 25% by weight brine in 31 kg of water) (40 kg), and brine (25% by weight, 92 kg), respectively. Next, the crude organic solution was treated with CUNO® by filtering it through a cartridge, and the filtrate was concentrated to approximately 30 L under reduced pressure at NMT 40°C. Then, the crude residue was crystallized by adding n-heptane (57 kg) together with seed crystals (0.040 kg).

[0265] Next, the crude product was further purified by recrystallization using a mixture of dimethylammonium and n-heptane to obtain purified compound A as a white solid. HRMS (ESI+) C 55 H 78 Calculated value for FN9O8(M+H): 1012.6036 Measured value: 1012.6065 1H NMR (400 MHz, CD3OD, 23℃) δ 8.71 (dd J = 4.8, 1.6 Hz, 1H), 7.83 (d, J = 7.2 Hz, 1H), 7.50 (dd, J = 8.0, 4.8 Hz, 1H), 7.39 (d, J = 8.0 Hz, 1H), 7.11 (s, 1H), 7.07 (dd, J = 9.0, 2.0 Hz, 1H), 5.67 (d, J = 8.8 Hz, 1H), 4.62 and 4.52 (d, J = 10.0 Hz, 1H, as rotamers), 4.46 (d, J = 12.4 Hz, 1H), 4.28-4.37 (m, 2 H), 4.24 (q (J = 6.4 Hz, 1H), 4.12-4.17 (m, 1H), 3.50-4.00 (m, 9H), 3.28 (d, J = 10.8 Hz, 1H), 3.10-3.20 and 2.90-3.00 (m, 8H, as rotamers), 2.60-2.80 (m, 4H), 2.35 (s, 3H), 2.34 (s, 3H), 2.05-2.35 (m, 7H), 1.85-1.95 (m, 2H), 1.60-1.73 (m, 2H), 1.46 (s, 3H), 1.45 (s, 3H), 1.44 (s, 3H), 0.96 and 1.02 (d, J = 6.4 Hz, 3H, as rotational isomer), 1.00-1.10 (m, 3H), 0.83 and 0.87 (dd, J = 6.8, 2.0 Hz, 3H, as rotational isomer), (0.77 (bs, 3H), 0.64 (bs, 3H).

[0266] Part 6 - Direct Synthesis of Compound A Without Isolating Compound 15 Alternatively, compound A can be prepared using a telescoping process that avoids the isolation and characterization of compound 15. This process allows for a more robust and cost-effective process.

[0267] Compound 14 (34.8 kg), 10% Pd / C (water-wet, 0.20X), THF (5V), and iPrOH (3V) were added to a pressure reactor. The mixture was stirred at 30-40°C for 32 hours under hydrogen (0.5 MPa). After the reaction was complete, monitored by HPLC, the atmosphere was changed to N2, and the reaction mixture was filtered through a diatomaceous earth pad to remove the used Pd / C catalyst. The used filter aid was washed with a mixture of THF and iPrOH. The combined filtrate and silica-thiol scavenger (0.1X) were mixed together at 20-30°C for 14 hours to remove residual palladium. The mixture was filtered, and the used scavenger was washed with a mixture of THF and iPrOH. The filtrate was concentrated to 3V under reduced pressure and diluted with DMF (3V).

[0268] Compound 2 (0.60 equivalents), DIPEA (5.5 equivalents), and DMF (9V) were added to a concentrated solution of Compound 15. The mixture was cooled to -50 to -10°C. Oxyma (1.1 equivalents) and PyBOP (1.2 equivalents) were rapidly and continuously added as a solution in DMF (2V) at -40 to -30°C over a period of no more than 30 minutes. The reaction mixture was stirred at -20 to -10°C for 3 hours. Reaction monitoring by HPLC indicated that the reaction was complete.

[0269] The crude reaction mixture was added dropwise over 1 hour to a mixture of SiO(20 kg) and 25 wt% brine (30 V). The two-phase mixture was stirred at 20-30°C for 1 hour and filtered through diatomaceous earth (0.5 X). The used filter aid was washed with SiO(1 V). The combined organic phase was washed twice with 25 wt% brine (20 V) and partitioned with 0.6 M HCl (aqueous solution) (18 V) at 10-20°C. The dilute organic layer was extracted with 0.6 M HCl (aqueous solution) (8 V). The combined rich aqueous phase was washed three times with SiO(10 V), partitioned with SiO(10 V), and neutralized to pH 9.0-10.0 at 10-20°C with 30 wt% Na2CO3 (aqueous solution) (approx. 7.2 X). The dilute aqueous layer was washed with SiO(10 V). The combined organic layers were sequentially washed twice with 25 wt% brine (20V), twice with 0.2 wt% AcOH and 3 wt% NaCl aqueous solution (10V), once with 3 wt% Na2CO3 and 5 wt% NaCl aqueous solution (10V), and once with 25 wt% brine (20V), and then filtered through a carbon filter. The reactor and filter were rinsed with SiO. The combined filtrate was concentrated to 7-8V under reduced pressure at less than 40°C and added to a mixture of n-heptane (21.6V) and seed crystal (0.7 wt%) at 25-35°C. The resulting slurry was cooled to 15-25°C over 4 hours, aged for 8 hours, and filtered. The solid was washed with a 3:1 mixture of n-heptane and SiO (2.0X) and dried under reduced pressure at 40-50°C for 30 hours to obtain crude compound A as a white solid.

[0270] Part 7 - Purification of Compound A Crude compound A was dissolved in toluene (4.0V) and treated with water (0.08X) and DIPEA (0.015X). The solution was stirred at 35-45°C for 30 minutes. n-heptane (4.0V) was added over 30 minutes at 35-45°C. Seed crystals (1 wt%) were added at 35-45°C. The mixture was stirred at 35-45°C for 8 hours. The resulting slurry was cooled to 20-30°C over 6 hours, aged for 30 minutes with stirring, heated to 35-45°C over 1 hour, and aged for 30 minutes. The temperature cycle was repeated one or two more times. A 10.5:1 (v / v) mixture of n-heptane / toluene (6.1X) was added over 6 hours. The slurry was cooled to 5-15°C over 8 hours, aged for 8 hours, and filtered. The solid was washed twice with a 2.5:1 (v / v) mixture of n-heptane / siRNA (2.0V), and dried under reduced pressure at 50°C to obtain compound A as a white solid.

[0271] Other Embodiments While the present invention is described in relation to its specific embodiments, it should be understood that the invention is subject to further modifications, and this application is intended to encompass any variations, uses, or adaptations of the invention, including any deviations from this disclosure that, generally in accordance with the principles of the invention, are included in known or customary practices of the relevant art and can be applied to the essential features described herein.

[0272] All publications, patents, and patent applications are incorporated herein by reference in their entirety, just as each individual publication, patent, or patent application is specifically and individually indicated to be incorporated by reference in its entirety.

Claims

1. Barium salt of compound 1. 【Chemistry 1】

2. The barium salt according to claim 1, wherein the barium salt has a carboxylic acid:barium ratio of 2:

1.

3. The barium salt according to claim 1 or 2, wherein the barium salt has the structure of compound 2. 【Chemistry 2】

4. Structure of compound 3: 【Transformation 3】 A compound having, or a salt thereof.

5. The structure of the compound 3a is: 【Chemistry 4】 A compound according to claim 4, or a salt thereof, having the properties of claim 4.

6. A method for preparing compound 4a, comprising contacting compound 4 with one or more ketoreductase enzymes to produce compound 4a. 【Transformation 5】

7. The method according to claim 6, wherein compound 4a is formed in a yield of at least 85%.

8. The tetramethylethylenediamine (TMEDA) salt of compound 5. 【Transformation 6】

9. The 1,4-diazabicyclo[2.2.2]octane (DABCO) salt of compound 5. 【Transformation 7】

10. A method for preparing compound 6, which includes: 【Transformation 8】 a) Bis-N-methylating compound 7 to form compound 7c: 【Chemistry 9】 b) Carboxylating compound 7c to form compound 7a: 【Chemistry 10】 c) Protonating compound 7a to form compound 7b: 【Chemistry 11】 d) Protonating compound 7b to form compound 6: 【Chemistry 12】 Methods that include...

11. The method according to claim 10, wherein the bis-N-methylation step (a) includes contacting compound 7 with an alkylating agent and a reducing agent.

12. A method for preparing compound 8, which includes: 【Chemistry 13】 Compound 9 and Compound 10: 【Chemistry 14】 A method comprising contacting the two in the presence of an acid and water.

13. A method for preparing compound 8, which includes: 【Chemistry 15】 a) Coupling compound 4b and compound 20 to form compound 21: 【Chemistry 16】 b) Contacting compound 21 and compound 10 to form compound 8: 【Chemistry 17】 Methods that include...

14. Hemisulfate of compound 8 (compound 8:sulfate in a 2:1 ratio). [Chemistry 18]

15. A method for preparing the hemisulfate according to claim 14, comprising contacting the free base of compound 8 with sulfuric acid.

16. A method for preparing compounds 11a and 11b, 【Chemistry 19】 a) Reducing compound 22 to form compound 23. 【Chemistry 20】 b) Alkylation of compound 23 to form a mixture of compounds 11a and 11b. 【Chemistry 21】 Methods that include...

17. A method for preparing compounds 11a and 11b, 【Chemistry 22】 a) Alkylating compound 22 to form compound 24. 【Chemistry 23】 b) Reducing compound 24 to form a mixture of compounds 11a and 11b. 【Chemistry 24】 Methods that include...

18. A method for separating compound 11a and compound 11b: 【Chemistry 25】 a) Heating a mixture of compound 11a and compound 11b in a solvent or a mixture of solvents for a certain period of time; b) forming a mixture of a salt of compound 11a and a salt of compound 11b; and c) Separating the mixture of salts of compound 11a and compound 11b. Methods that include...

19. The method according to claim 18, wherein the separation is carried out in a flow process.

20. A method for preparing compound 3a: 【Chemistry 26】 a) Deprotonate compound 3b with a chiral base to form a diastereomer salt of compound 3b: 【Chemistry 27】 b) Reducing the diastereomer salt of compound 3b to form compound 3c: 【Chemistry 28】 c) Coupling compound 3c with compound 3d or a salt thereof to form compound 3e; 【Chemistry 29】 d) Hydrolyzing compound 3e to form compound 3a: 【Transformation 30】 Methods that include...

21. A method for preparing compound A: 【Chemistry 31】 a) Coupling compound 11a and compound 3a to form compound 12: 【Chemistry 32】 b) Deprotecting compound 12 to form compound 13: 【Transformation 33】 c) Coupling compound 13 to form compound 14: 【Transformation 34】 f) Deprotecting compound 14 to form compound 15: 【Chemistry 35】 e) Coupling compound 15 and compound 2 to form compound A: 【Transformation 36】 Methods that include...

22. Structure of compound 12: 【Chemistry 37】 A compound having, or a salt thereof.

23. Compound having the structure of compound 13: 【Transformation 38】 or its salt.

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