Methods for synthesizing diazabicyclo[6.2.0]decane-related compounds

Abstract

The present application provides a method for synthesizing diazabicyclo[6.2.0]decane compounds. The synthesis proceeds through the stereoselective synthesis of a chiral lactone, followed by a series of chemoselective reactions to form an azetidine. The diazabicyclo[6.2.0]decane related compounds are formed by a bi-cyclization.

Description

[0001] Statement of Government Support

[0002] This invention was made with government support under the Department of Defense Peer Reviewed Medical Research Program Grant Number: W81XWH-16-1-0719. The government has certain rights in the invention.

[0003] Cross Reference to Related Applications

[0004] This application claims priority to U.S. Provisional Patent Application No. 62 / 790,340, filed January 9, 2019, which is incorporated herein by reference. TECHNICAL FIELD

[0005] The present invention relates to stereochemically defined synthesis for the production of 1,6-diazabicyclo[6.2.0]decane. BACKGROUND

[0006] Malaria is an infectious disease caused by protozoan parasites of the genus Plasmodium. Malaria is difficult to eradicate due to the complex life cycle of the Plasmodium and the emergence of parasite drug resistance. Diversity-oriented synthesis (DOS) has been used to identify anti-malarial compounds. For example, the phenylalanyl-tRNA synthetase inhibitor BRD7929 has been identified. BRD7929 exhibits activity at all stages of the parasite life cycle.

[0007] BRD7929 has the chemical name (8R,9S,10S)-10-[(dimethylamino)methyl]-N-(4- methoxyphenyl)-9-[4-(2-phenylethynyl)phenyl]-1,6-diazabicyclo[6.2.0]decane-6- carboxamide, which is reported in U.S. Patent Application Publication No. US2016 / 0289235, which is incorporated herein by reference. BRD7929 has the following structure:

[0008]

[0009] Likewise, the compound shown below (Formula XIV, or Compound 22) has also been identified as useful for treating and / or preventing diseases transmitted by parasites, including malaria and cryptosporidiosis:

[0010]

[0011] See WO2018 / 175385, which is incorporated by reference herein in its entirety.

[0012] Additional related compounds and their synthesis, also claimed to be useful in therapies against diseases transmitted by parasites, including for example malaria and cryptosporidiosis, can be found in WO2018 / 175385; Lowe, J. T. et al., Synthesis and profiling of a diverse collection of azetidine-based scaffolds for the development of CNS-focused lead-like libraries, J. Org. Chem. 77, 7187-7211 (2012); Maetani, M. et al., Synthesis of a Bicyclic Azetidine with In Vivo Antimalarial Activity Enabled by Stereospecific, Directed C(sp 3 )-H Arylation, J. A. C. S. 139, 11300-11306 (2017); and Kato, N. et al., Diversity-oriented synthesis yields novel multistage antimalarial inhibitors, Nature 538, 344-349 (2016), all of which are incorporated by reference in their entirety.

[0013] Additional literature related to the preparation of compounds useful in and for the treatment of parasitic diseases includes the following: WO2015070204, WO2015002755, WO2016172631, and US2018 / 0194768; all of which are incorporated by reference in their entirety.

[0014] However, lengthy, low-yielding, and / or expensive synthetic routes limit the use of this compound. BRD7929, Formula XIV, and related compounds are known to have therapeutic value, and improving the synthetic routes for their production can provide further medicinal chemistry exploration of this class of compounds while reducing the cost of production, thereby making the development and / or widespread availability of these therapeutics more feasible. Thus, there is a need for improved synthesis for the preparation of these potential antimalarial compounds. SUMMARY

[0015] One embodiment relates to a method of forming a solid compound of Formula I:

[0016]

[0017] In Formula I, R1is -I, -CI, -Br, or R2is C(O)R3; R3is -O - ; and a cation is associated with the ion of formula I; and P1is a nitrogen protecting group. The method comprises reacting a reactant of formula II

[0018] and resolving the racemic mixture by crystallization with a chiral reagent.

[0019] In one embodiment, R1is

[0020] In another embodiment, P1is selected from the group consisting of -C(O)CF3, -C(O)OC(CH3)3, and -C(O)OCH2Ph.

[0021] In another embodiment, P1is -C(O)CF3.

[0022] In another embodiment, in the reaction, the base is lithium diisopropylamine and the reaction is conducted in the presence of ZnCl2.

[0023] In another embodiment, the chiral reagent is (R)-(+)-1-phenylethylamine.

[0024] In another embodiment, the method for forming a compound of formula I, R1is -I, -Cl, -Br, or

[0025] R2is C(O)R3; R3is -Oalkyl; and P1is a nitrogen protecting group. The method comprises reacting a reactant of formula III

[0026]

[0027] wherein X1is a halogen atom.

[0028] In one embodiment, R1and X1are each -Br and the chiral sulfinimine is R4and R5are linear or branched alkyl.

[0029] In another embodiment, R4is -C(CH3)3and R5is -CH2CH3.

[0030] In another embodiment, the reaction is conducted in the presence of Zn.

[0031] Another embodiment can involve a method for forming a compound of formula IV:

[0032]

[0033] In Formula IV, R1is -I, -Cl, -Br, or P1and P2are the same or different and represent a nitrogen protecting group. The method comprises reducing a lactone of Formula V

[0034]

[0035] forming a lactone of Formula V,

[0036]

[0037] wherein R2is C(O)R3; R3is -OH, -Oalkyl, -O - ; when R3is -O - , a cation is associated with the ion of Formula I; and, P1is a nitrogen protecting group; reducing the lactone of Formula V to a compound of Formula VI:

[0038]

[0039] converting the alcohol group covalently attached to the unsaturated carbon of Formula VI to a leaving group to form an intermediate, which reacts with a nitrogen nucleophile to produce a compound of Formula IV.

[0040] In one embodiment, the nitrogen nucleophile is phthalimide.

[0041] In another embodiment, R1is R2is -C(O)O - , and P1is -C(O)CF3.

[0042] In another embodiment, the lactone of Formula V is formed by reacting a compound of Formula I with a source of positive electronegativity of a halogen in a polar solvent.

[0043] In another embodiment, the source of positive electronegativity of a halogen is I2, and the polar solvent is an aqueous mixture of CH3CN. Those skilled in the art will readily recognize that a variety of polar solvents can be used, including but not limited to water, an aqueous solution of THF, an aqueous solution of DMF, or other polar protic or polar aprotic water-miscible solvents.

[0044] In another embodiment, the lactone of Formula V is formed by reacting a compound of Formula I with I2in a polar solvent to form a first product, and reacting the first product with NaN3to form the compound of Formula V.

[0045] In another embodiment, the reduction is carried out with NaBH4.

[0046] In another embodiment, the leaving group is a mesylate group, and the intermediate is represented by one or both of the following structures:

[0047]

[0048] In another embodiment, P1is converted from -C(O)CF3to the following structure:

[0049]

[0050] In another embodiment, R1is -Br, R2is -C(O)OCH2CH3, and P1is -S(O)C(CH3)3.

[0051] In another embodiment, P1is converted from -S(O)C(CH3)3to the following structure:

[0052] In another embodiment, the lactone of formula V is formed by reacting a compound of formula I with a source of positive charge of a halide in a polar solvent to form a first product, and reacting the first product with NaN3to form the compound of formula V.

[0053] In another embodiment, the lactone of formula V is reduced with NaBH4to form the following compound:

[0054]

[0055] In another embodiment, the leaving group is a mesylate group, and the intermediate is represented by one or both of the following structures:

[0056]

[0057]

[0058] Another embodiment can involve a method of making a compound represented by the structure of formula VIII:

[0059]

[0060] In formula VIII, R1is -I, -Cl, -Br, or R6and R7are independently the same or different and selected from -H, alkyl, -Oalkyl, or wherein R6and R7together with the atoms to which they are attached form a ring; R8and R9are independently the same or different and selected from -H, -alkyl, -C(O)alkyl, -S(O)2alkyl, or R8and R9together with the N to which they are attached form a monocyclic or bicyclic ring system; R 10-H, straight or branched chain alkyl, -C(O)alkyl, -C(O)O-alkyl, -C(O)NH-alkyl, -C(O)aryl, -C(O)O-aryl, -C(O)NH-aryl, -C(O)heteroaryl, -C(O)O-heteroaryl, and -C(O)N-heteroaryl; wherein alkyl, aryl and heteroaryl are optionally substituted with one or more halogen, oxygen, nitrogen, or sulfur atoms. The method includes reacting a compound of Formula IV with a substituted γ-hydroxyaldehyde, and, effecting a bicyclization

[0061]

[0062] In one embodiment, the γ-hydroxyaldehyde is represented by the following structure:

[0063]

[0064] wherein R 11 is -H or an oxygen protecting group; and, R 12 is -H or -CH2OH.

[0065] In another embodiment, the γ-hydroxyaldehyde is

[0066]

[0067] and the compound of Formula VIII is prepared via the following intermediate:

[0068]

[0069] In another embodiment, the method further includes oxidizing and preparing the compound of Formula VIII via the following intermediate:

[0070]

[0071] In another embodiment, the method further includes reducing, bicyclizing, and preparing the compound of Formula VIII via the following intermediate:

[0072]

[0073] In another embodiment, the method further includes reducing and preparing the compound of Formula VIII via the following intermediate:

[0074]

[0075] In another embodiment, the compound of Formula XIII is reacted with 4-methoxyphenyl isocyanate and the compound of Formula VIII is represented by the following structure:

[0076]

[0077] Another object of the present invention relates to a method of forming a compound of Formula IV,

[0078]

[0079] In Formula IV, R1is -I, -Cl, -Br, or P1and P2are the same or different and represent a nitrogen protecting group. The method includes converting an alcohol group covalently attached to an unsaturated carbon of Formula VI to a leaving group to form an intermediate, which reacts with a nitrogen nucleophile to produce a compound of Formula IV

[0080]

[0081] In one embodiment, the leaving group is methanesulfonate, and the intermediate is represented by one or both of the following structures,

[0082]

[0083] In another embodiment, the nitrogen nucleophile is phthalimide.

[0084] One beneficial finding of the present invention is a chemoselective tandem process to make substituted azetidines. This can be the first example of a tailored nucleophilic aziridine ring opening that preferentially displaces an oxygen leaving group or one of the first to emphasize the importance of ring strain energy release in controlling chemical reactivity. Another beneficial finding of the present invention is the application of an aza-Wittig / reduction sequence to construct an eight-membered ring directly from an azido-aldehyde.

[0085] Another embodiment relates to a compound of Formula I:

[0086] wherein in Formula I, R1is R2is C(O)R3; R3is -O - and a cationic counterion is associated with the ion of Formula I, or R3is -OH; and P1is a nitrogen protecting group or -H.

[0087] Another embodiment relates to a compound of Formula IV:

[0088]

[0089] In Formula IV, R1is -I, -Cl, -Br, or and P1and P2are the same or different and represent a nitrogen protecting group or -H.

[0090] Another embodiment is directed to a compound of Formula V:

[0091]

[0092] In Formula V, R1is -I, -Cl, -Br, or and P1is a nitrogen protecting group or -H.

[0093] Another embodiment is directed to a compound of Formula VI:

[0094]

[0095] In Formula VI, R1is -I, -Cl, -Br, or and P1is a nitrogen protecting group or -H.

[0096] Another embodiment is directed to a compound of Formula VII:

[0097]

[0098] In Formula VII, R1is -I, -Cl, -Br, or and P1is a nitrogen protecting group or -H.

[0099] Another embodiment is directed to a compound of Formula VIIb:

[0100]

[0101] In Formula VIIb, R1is -I, -Cl, -Br, or and P1is a nitrogen protecting group or -H.

[0102] Another embodiment is directed to a compound of Formula VIII:

[0103]

[0104] In Formula VIII, R1is -I, -Cl, -Br, or R6and R7are independently the same or different and selected from the group consisting of -H, alkyl, -Oalkyl, or wherein R6and R7together with the atoms to which they are attached form a ring; R8and R9are independently the same or different and selected from the group consisting of -H, -alkyl, -C(O)alkyl, -S(O)2alkyl, or R8and R9together with the N to which they are attached form a monocyclic or bicyclic ring system; and R 10-H, straight or branched chain alkyl, -C(O)alkyl, -C(O)O-alkyl, -C(O)NH-alkyl, -C(O)aryl, -C(O)O-aryl, -C(O)NH-aryl, -C(O)heteroaryl, -C(O)O-heteroaryl, and -C(O)N-heteroaryl, wherein the alkyl, aryl and heteroaryl groups are substituted with one or more hydrogen, halogen, oxygen, nitrogen, or sulfur atoms.

[0105] Another embodiment is directed to a compound of Formula X:

[0106]

[0107] In Formula X, R1is -I, -Cl, -Br, or and R8and R9are independently the same or different and selected from the group consisting of -H, -alkyl, -C(O)alkyl, -S(O)2alkyl, or R8and R9together with the N to which they are attached form a monocyclic or bicyclic ring system, wherein the alkyl groups are substituted with one or more hydrogen, halogen, oxygen, nitrogen, or sulfur atoms.

[0108] Another embodiment is directed to a compound of Formula XI:

[0109]

[0110] In Formula XI, R1is -I, -Cl, -Br, or and R8and R9are independently the same or different and selected from the group consisting of -H, -alkyl, -C(O)alkyl, -S(O)2alkyl, or R8and R9together with the N to which they are attached form a monocyclic or bicyclic ring system, wherein the alkyl groups are substituted with one or more hydrogen, halogen, oxygen, nitrogen, or sulfur atoms.

[0111] Another embodiment is directed to a compound of Formula XII:

[0112]

[0113] In Formula XII, R1is -I, -Cl, -Br, or and R8and R9are independently the same or different and selected from the group consisting of -H, -alkyl, -C(O)alkyl, -S(O)2alkyl, or R8and R9together with the N to which they are attached form a monocyclic or bicyclic ring system, wherein the alkyl groups are substituted with one or more hydrogen, halogen, oxygen, nitrogen, or sulfur atoms.

[0114] Another embodiment is directed to a compound of Formula XIII:

[0115]

[0116] In Formula XIII, R1is -I, -Cl, -Br, or R8and R9are independently the same or different and selected from the group consisting of -H, -alkyl, -C(O)alkyl, -S(O)2alkyl, or R8and R9together with the N to which they are attached form a monocyclic or bicyclic ring system, wherein the alkyl groups are substituted with one or more halogen, hydrogen, oxygen, nitrogen, or sulfur atoms.

[0117] Another embodiment is directed to a compound represented by Formula XV:

[0118]

[0119] In Formula XV, R1is -I, -Cl, -Br, or and,

[0120] Z is a four-membered nitrogen-containing heterocyclic ring selected from any of:

[0121]

[0122] P1and P2are the same or different and are a nitrogen protecting group or -H;

[0123]

[0124] R6and R7are independently the same or different and selected from the group consisting of -H, alkyl, -Oalkyl, or wherein R6and R7together with the atoms to which they are attached form a ring; R8and R9are independently the same or different and selected from the group consisting of -H, -alkyl, -C(O)alkyl, -S(O)2alkyl, or R8and R9together with the N to which they are attached form a monocyclic or bicyclic ring system; and R 10 -H, straight or branched chain alkyl, -C(O)alkyl, -C(O)O-alkyl, -C(O)NH-alkyl, -C(O)aryl, -C(O)O-aryl, -C(O)NH-aryl, -C(O)heteroaryl, -C(O)O-heteroaryl, and -C(O)N-heteroaryl, wherein the alkyl, aryl, and heteroaryl groups are substituted with one or more halogen, hydrogen, oxygen, nitrogen, or sulfur atoms;

[0125]

[0126] R8and R9are independently the same or different and selected from the group consisting of -H, -alkyl, -C(O)alkyl, -S(O)2alkyl, or R8and R9together with the N to which they are attached form a monocyclic or bicyclic ring system, wherein the alkyl groups are substituted with one or more halogen, hydrogen, oxygen, nitrogen, or sulfur atoms.

[0127]

[0128] R8and R9are independently the same or different and selected from the group consisting of -H, -alkyl, -C(O)alkyl, -S(O)2alkyl, or R8and R9together with the N to which they are attached form a monocyclic or bicyclic ring system, wherein the alkyl is optionally substituted with one or more halogen, hydrogen, oxygen, nitrogen, or sulfur atoms;

[0129]

[0130] R8and R9are independently the same or different and selected from the group consisting of -H, -alkyl, -C(O)alkyl, -S(O)2alkyl, or R8and R9together with the N to which they are attached form a monocyclic or bicyclic ring system, wherein the alkyl is optionally substituted with one or more halogen, hydrogen, oxygen, nitrogen, or sulfur atoms;

[0131]

[0132] R8and R9are independently the same or different and selected from the group consisting of -H, -alkyl, -C(O)alkyl, -S(O)2alkyl, or R8and R9together with the N to which they are attached form a monocyclic or bicyclic ring system, wherein the alkyl is optionally substituted with one or more halogen, hydrogen, oxygen, nitrogen, or sulfur atoms.

[0133] Another embodiment is directed to a compound represented by Formula XV:

[0134]

[0135] In Formula XV, R1is -I, -Cl, -Br, or

[0136] wherein in Formula XV, Z is selected from one of the following:

[0137]

[0138] R2is C(O)R3; R3is -O - and the positive counterion is associated with the ion of Formula XVI, or R3is -OH; and P1is a nitrogen protecting group or -H;

[0139]

[0140] P1is a nitrogen protecting group or -H;

[0141]

[0142] P1is a nitrogen protecting group or -H;

[0143]

[0144] P1is a nitrogen protecting group or -H; and

[0145]

[0146] P1is a nitrogen protecting group or -H;

[0147] or a pharmaceutically acceptable salt thereof.

[0148] The compounds provided herein, including but not limited to the compounds of Formulae I, IV, V, VI, VII, VIIb, VIII, X, XI, XII, XIII, and XV, can be provided as pharmaceutically acceptable salts. As used herein, "pharmaceutically acceptable salts" within the present disclosure refer to the acid addition or base addition salts of the compounds. Pharmaceutically acceptable salts are any salts of the parent compound that retain its activity and do not impart any undesired harmful or undesirable effects on the subject to whom it is administered and in the environment in which it is administered. Pharmaceutically acceptable salts include, but are not limited to, metal salts, and salts of inorganic and carboxylic acids. Pharmaceutically acceptable salts also include, for example, metal salts and complex salts of aluminum, calcium, iron, magnesium, manganese. Further, pharmaceutically acceptable salts include, but are not limited to, acid salts such as acetate, aspartate, alkyl sulfonate, aryl sulfonate, axetil, benzenesulfonate, benzoate, bicarbonate, bisulfuric, bitartrate, butyrate, calcium edetate, camsylic, carbonate, chlorobenzoate, citrate, edetate, edisylic, estolic, esyl, esylic, formate, fumarate, gluceptic, gluconic, glutamate, glycolic, glycolylarsanilic, hexamic, hexylresorcinoic, hydrabamic, hydrobromic, hydrochloric, hydroiodic, hydroxynaphthoate, isethionic, lactic, lactobionic, maleate, malic, malonic, mandelic, mesylic, methylnitrate, methylsulfate, mucic, muconic, napsylic, nitric, oxalic, p-nitromethanesulfonate, pamoate, pantothenic, phosphoric, monohydrogen phosphate, dihydrogen phosphate, phthalic, polygalacturonic, propionic, salicylate, stearic, succinate, sulfamic, sulfanilic, sulfonic, sulfuric, tannic, tartaric, teoclic, tosylate, and the like. Pharmaceutically acceptable salts can be derived from amino acids, including but not limited to cysteine.Methods of producing compounds as salts are known to those skilled in the art (see, e.g., Stahl et al., Handbook of Pharmaceutical Salts: Properties, Selection, and Use, Wiley-VCH; Verlag Helvetica Chimica Acta, Zurich, 2002; Berge et al., J. Pharm. Sci. 66: 1, 1977).

[0149] Other aspects and advantages of the present application will be apparent from the following description, the drawings and the appended claims. BRIEF DESCRIPTION OF DRAWINGS

[0150] Figure 1 Figure 1 An ORTEP projection of compound 5 is shown.

[0151] Figure 2 Figure 2 An ORTEP projection of compound 32 is shown. DETAILED DESCRIPTION

[0152] Although the terms used herein are believed to be well understood by one of ordinary skill in the art, definitions are set forth herein to facilitate explanation of the subject matter disclosed herein.

[0153] Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which the subject matter disclosed herein belongs. Although any methods, devices, and materials similar or equivalent to those described herein can be used in the practice or testing of the presently disclosed subject matter, representative methods, devices, and materials are described herein.

[0154] All combinations or process steps described herein can be performed in any order, unless otherwise specified or clearly implied to the contrary by the context in which the referenced combinations are made.

[0155] The methods and apparatus of the present disclosure, including components thereof, can comprise, consist of, or consist essentially of the essential elements and limitations described herein, in addition to any additional or optional components or limitations described herein or otherwise useful; or be substantially similar to the essential elements and limitations described herein, in addition to any additional or optional components or limitations described herein or otherwise useful.

[0156] ​​Unless otherwise indicated, all numbers expressing quantities of ingredients, properties such as physical dimensions, quantities, numbers of steps, etc. used herein are to be understood as approximations as opposed to being exact. It is intended that the description and examples be considered as exemplary of the disclosed subject matter and not as a limitation thereof. Thus, it is intended that the scope of the disclosed subject matter be defined by the claims appended hereto rather than by the description and examples given.

[0157] The term "alkyl" includes branched, straight-chain and cyclic, substituted or unsubstituted saturated aliphatic hydrocarbon groups. Alkyl groups can contain from about 1 to about 24 carbon atoms ("C1-C24"), from about 7 to about 24 carbon atoms ("C7-C24"), from about 8 to about 24 carbon atoms ("C8-C24"), or from about 9 to about 24 carbon atoms ("C9-C24"). Alkyl groups can also contain from about 1 to about 8 carbon atoms ("C1-C8"), from about 1 to about 6 carbon atoms ("C1-C6"), or from about 1 to about 3 carbon atoms ("C1-C3"). Examples of C1-C6alkyl groups include, but are not limited to, methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, t-butyl, pentyl, isopentyl, neopentyl, hexyl, isohexyl, cyclohexyl, cyclohexylmethyl, cyclopropylmethyl, and neohexyl radicals.

[0158] The term "aryl" includes 6- to 14-membered monocyclic, bicyclic, or tricyclic aromatic hydrocarbon ring systems. Examples of aryl groups include phenyl and naphthyl.

[0159] The term "heteroaryl" includes 5- to 14-membered aromatic heterocyclic rings having at least one heteroatom selected from nitrogen, oxygen, and sulfur, and containing at least 1 carbon atom, including monocyclic, bicyclic, and tricyclic ring systems. Representative heteroaryl groups are triazolyl, tetrazolyl, oxadiazolyl, pyridyl, furanyl, benzofuranyl, thiophenyl, benzothiophenyl, quinolinyl, pyrrolyl, indolyl, oxazolyl, benzoxazolyl, imidazolyl, benzimidazolyl, thiazolyl, benzothiazolyl, isoxazolyl, pyrazolyl, isothiazolyl, pyridazinyl, pyrimidinyl, pyrazinyl, triazinyl, cinnolinyl, phthalazinyl, quinazolinyl, pyrimidyl, oxetanyl, azepinyl, piperazinyl, morpholinyl, dioxanyl, thietanyl, and oxazolyl.

[0160] Oxygen protecting groups include, but are not limited to, for example, benzyl or substituted benzyl, silyl or substituted silyl, acetyl or other ester protecting groups, methoxy methyl or other methoxy ethers. Those skilled in the art will recognize other acceptable protecting groups as identified in Greene’s Protective Groups in Organic Synthesis, Fifth ed., Peter G. M. Wuts, John Wiley & Sons, Inc. (2014), which is incorporated herein by reference in its entirety.

[0161] Those skilled in the art will recognize a variety of nitrogen protecting groups that can be used in accordance with embodiments of the present application. See also Greene’s Protective Groups in Organic Synthesis, Fifth ed., which is incorporated herein by reference in its entirety. Useful nitrogen protecting groups can include, for example, but are not limited to, 9-fluorenylmethyl carbamate; t-butyl carbamate; 2-nitrobenzenesulfonyl; 4-nitrobenzenesulfonyl; benzyl carbamate; acetamide; trifluoroacetamide; phthalimide; benzylamine; triphenylmethylamine; benzylideneamine; and p-toluenesulfonamide.

[0162] Abbreviations. XPhos-Pd-G3 (XPhos G3) is (2-dicyclohexylphosphino-2',4',6'-triisopropyl-1,1'-biphenyl)[2-(2'-amino-1,1'-biphenyl)]palladium(II) methanesulfonate, XPhos-G3-cyclo palladium complex (Sigma-Aldrich). Dess Martin periodinane is 1,1,1-tris(acetyloxy)-1,1-dihydro-1,2-benziodoxol-3-(1H)-one (Sigma-Aldrich). MTBE is methyl tert-butyl ether. As used herein, “Ns” or “nosyl” refers to 2-nitrobenzenesulfonyl; “Ms” or “mesyl” refers to methylsulfonyl; and “TFA” refers to trifluoroacetyl.

[0163] While only certain stereoisomers are presented in any given claim, those skilled in the art will appreciate that the enantiomers or other stereoisomers can be prepared by manufacturing the appropriate corresponding chiral starting materials or intermediates.

[0164] If there is a discrepancy between the depicted structure and the nomenclature used to designate the structure, the depicted structure controls. In addition, if the stereochemistry of a structure or a portion of the structure is not specified, the structure or portion thereof is intended to encompass all stereochemistry.

[0165] Synthesis of Route A

[0166] Esterification of 4-bromocinnamic acid to produce ((E)-3-(4-bromophenyl)propenoic acid methyl ester) 1

[0167]

[0168] Sulfoxyl chloride (176 mL, 2422 mmol) was added dropwise to a white suspension of 4-bromocinnamic acid (500 g, 2202 mmol) in methanol (3000 mL) over 20 minutes, maintaining the reaction temperature below 40 °C. The mixture was then heated to reflux for 1 hour, during which time it gradually homogenized. The solution was allowed to slowly come to room temperature to produce a white suspension. This was filtered and the filter cake was washed twice with cold methanol to produce 1 as a white solid. The filtrate was concentrated to half the original volume and filtered again, washing the filter cake with cold methanol. This procedure was repeated twice more to produce additional 1 (523 g combined, 98% yield).

[0169] 1 H NMR (400 MHz, CDC13) δ 7.62 (d, J = 16.0 Hz, 1H), 7.52 (d, J = 8.2 Hz, 2H), 7.38 (d, J = 8.6 Hz, 2H), 6.43 (d, J = 16.0 Hz, 1H), 3.81 (s, 3H); 13 C NMR (75 MHz, CDC13) δ 167.1, 143.4, 133.2, 132.1, 129.4, 124.5, 118.5, 51.8.

[0170] Sonogashira reaction of 1 to produce ((E)-3-(4-(phenylethynyl)phenyl)propenoic acid methyl ester) 2

[0171]

[0172] Dissolve 1 (285 g, 1180 mmol) in diisopropylamine (2500 mL) to form a clear, homogeneous solution. After sparging with nitrogen for 30 minutes, add copper(I) iodide (0.169 g, 0.885 mmol), bis(cyanobenzyl) palladium(II) chloride (0.453 g, 1.18 mmol), and tri-tert-butylphosphonium tetrafluoroborate (0.685 g, 2.36 mmol). Heat the mixture to 80 °C, then add phenylacetylene (136 mL, 1239 mmol) in portions to initiate the reaction first, as indicated by the internal temperature rising to reflux and the formation of a precipitate, then maintain the reflux of the exothermic reaction. After the addition is complete, stir the mixture at 80 °C for an additional hour, then allow it to slowly come to 50 °C, at which point quench the reaction with water (2000 mL). Allow the mixture to come to room temperature while stirring, then filter. Wash the filter cake with water (200 mL x 3), then dry under vacuum at 40 °C to form 2 (296 g, 96%) as a white solid, which is pure according to NMR spectra.

[0173] 1 H NMR (400 MHz, CDC13) δ 7.69 (d, J = 16.0 Hz, 1H), 7.56 - 7.50 (m, 6H), 7.38 - 7.35 (m, 3H), 6.46 (d, J = 16.0 Hz, 1H), 3.83 (s, 3H); 13 C NMR (75 MHz, CDC13) δ 167.2, 143.9, 134.1, 132.0, 131.6, 128.5, 128.4, 128.0, 125.2, 122.9, 118.4, 91.6, 89.0, 51.7.

[0174] Reduce 2 to form ((E)-3-(4-(phenylacetylenyl)phenyl)prop-2-en-1-ol) 3

[0175]

[0176] Cool a clear, colorless solution of 2 (210 g, 801 mmol) in dichloromethane (3150 mmol) to -78 °C in a dry ice-acetone bath, during which the solution turns to a white suspension. After slowly adding a solution of diisobutylaluminum hydride (25 wt.% in toluene, 934 g, 1641 mmol), slowly allow the mixture to come to -20 °C over 12 hours. Carefully quench the reaction with a solution of potassium sodium tartrate tetrahydrate (926 g, 3282 mmol) in water (4200 mL), and stir the mixture at room temperature for 12 hours. Separate the two phases, and extract the aqueous phase with dichloromethane (1700 mL x 4). Dry the combined organic phases over anhydrous sodium sulfate and concentrate to form 3 (184 g, 98%) as a white solid, which is pure according to NMR spectra.

[0177] 1 H NMR (400 MHz, CDC13) δ 7.55-7.48 (m, 4H), 7.39-7.34 (m, 5H), 6.63 (d, J = 16.1 Hz, IH), 6.41 (dt, J = 16.0, 5.4 Hz, IH), 4.36 (dd, J = 5.5, 1.6 Hz, 2H); 13 C NMR (75 MHz, CDC13) δ 136.6, 131.8, 131.6, 130.4, 129.5, 128.3, 128.3, 126.4, 123.2, 122.4, 90.1, 89.4, 63.6.

[0178] Esterification of 3 with N-(trifluoroacetyl)glycine to form ((E)-3-(4-(phenylethynyl)phenyl)allyl (2,2,2-trifluoroacetyl)glycinate) 4

[0179]

[0180] A mixture of 3 (184 g, 785 mmol), N-(trifluoroacetyl)glycine (136 g, 793 mmol) and 4-(dimethylamino)pyridine (9.59 g, 78.5 mmol) was added to dichloromethane (1840 mL) to form a yellow suspension. It was cooled to 10 °C in an ice bath, at which time N,N'-diisopropylcarbodiimide (128 mL, 825 mmol) was added portionwise while maintaining the internal temperature below 15 °C. The mixture was allowed to slowly reach room temperature and stirred overnight. The mixture was filtered, and the filter cake was washed with dichloromethane (50 mL x 3). The filtrate was added to a mixture solvent of ethyl acetate / methyl tert-butyl ether (1:1, 3680 mL) and washed with aqueous sodium bicarbonate (400 mL x 2) and brine (400 mL). The organic phase was dried over anhydrous sodium sulfate and concentrated. The residue was crystallized in isopropanol to form 4 as a white solid (240 g, 79%).

[0181] 1 H NMR (400 MHz, CDC13) δ 7.56-7.50 (m, 4H), 7.40-7.34 (m, 5H), 6.90 (br s, IH), 6.6.69 (d, J = 15.6 Hz, IH), 6.31 (dt, J = 16.0, 6.6 Hz, IH), 4.88 (dd, J = 6.6, 1.1 Hz, 2H), 4.19 (d, J = 5.0 Hz, IH); 13C NMR (75 MHz, CDC13) δ 168.0, 135.5, 134.9, 131.9, 131.6, 128.4, 126.6, 123.3, 123.1, 122.5, 90.5, 89.1, 66.6, 41.4.

[0182] Claisen rearrangement 4 and chiral resolution using (R)-(+)-1-phenylethylamine to give ((R)-1-phenylethan-1-amin(2S,3S)-3-(4-(phenylethynyl)phenyl)-2-(2,2,2- trifluoroacetamido)4-pentenoic acid) 5

[0183]

[0184] Preparation of lithium diisopropylamide (LDA): A solution of diisopropylamine (22.8 mL, 160 mmol) in tetrahydrofuran (130 mL) was cooled in an ice bath and treated slowly with a solution of n-butyllithium (2.5 M in hexanes, 62.0 mL, 155 mmol) while maintaining the internal temperature below 20 °C. The ice bath was removed and the mixture was stirred at room temperature for 30 minutes.

[0185] In a separate vessel, a solution of 4 (20.0 g, 51.6 mmol) in tetrahydrofuran (140 mL) was cooled in a dry ice-acetone bath to give a yellow suspension. This was treated with a solution of zinc chloride (1.9 M in 2-methyltetrahydrofuran, 40.8 mL, 77.4 mmol) while maintaining the internal temperature below -60 °C. To this mixture was added slowly a solution of LDA while maintaining the internal temperature below -65 °C, during which time the mixture turned to a deep blue homogeneous solution near the end of the addition. The reaction mixture was maintained at this temperature for 60 minutes. The cooling bath was removed and the reaction mixture was allowed to reach room temperature slowly, during which time it turned to a deep orange color. The reaction was quenched with hydrochloric acid (1 M, 336 mL, 336 mmol) during which time the internal temperature rose to 35 °C. The two phases were separated and the aqueous phase was extracted with methyl tert-butyl ether (160 mL x 2). The combined organic phases were concentrated and the residue was taken up in methyl tert-butyl ether (160 mL). The mixture was heated to reflux temperature to give an approximately clear solution. This was treated with (R)-(+)-1-phenylethylamine (12.5 g, 103 mmol) to give a clear solution from which a precipitate began to form quickly. The mixture was allowed to reach room temperature slowly with stirring, then was cooled in an ice bath. The product was filtered, washed with methyl tert-butyl ether (20 mL x 2), and dried under vacuum to give 5 as a white solid (10.7 g, 40.8% yield, enantiomeric ratio (e.r.) = 16.8:1).

[0186] 1H NMR (400 MHz, MeOH-d4) δ 7.52-7.49 (m, 2H), 7.46-7.39 (m, 7H), 7.39-7.34 (m, 3H), 7.28 (d, J = 8.2 Hz, 2H), 6.24-6.14 (m, 1H), 5.13-5.09 (m, 2H), 4.70 (d, 8.2 Hz, 1H), 4.44 (q, J = 7.0 Hz, 1H), 3.86 (t, J = 8.2 Hz, 1H), 1.63 (d, J = 7.0 Hz, 3H); 13 C NMR (75 MHz, MeOH-d4) δ 175.5, 142.2, 140.1, 139.1, 132.7, 132.6, 130.5, 130.3, 130.0, 129.7, 129.5, 127.7, 124.9, 123.2, 117.4, 90.2, 90.1, 61.0, 54.3, 52.5, 21.0.

[0187] 5 was reacted with iodine and replaced with sodium azide to produce (N-((3S,4S,5S)-5-(azidomethyl)-2-oxo-4-(4-(phenylethynyl)phenyl)tetrahydrofuran-3-yl)-2,2,2-trifluoroacetamide) 7

[0188]

[0189] A white milky suspension of 5 (30.9 g, 60.8 mmol) in acetonitrile (494 mL) and water (124 mL) was cooled to 0 °C and treated with iodine (30.8 g) to produce a deep red solution which was stirred for 1 hour at the temperature. The reaction was quenched by treating the mixture with sodium thiosulfate (28.8 g, 182 mmol) and stirring for 10 minutes during which time it turned light yellow. The mixture was added to methyl tert-butyl ether (500 mL) and the two phases were separated. The organic phase was washed with 1 M hydrochloric acid (150 mL) and brine (150 mL). The aqueous phase was back extracted with methyl tert-butyl ether. The combined organic phases were dried over anhydrous sodium sulfate and concentrated to produce the crude product (2,2,2-trifluoro-N-((3S,4S,5S)-5-(iodomethyl)-2-oxo-4-(4-(phenylethynyl)phenyl)tetrahydrofuran-3-yl)acetamide) 6 as a red gum.

[0190] The above crude product 6 was added to N,N-dimethylformamide (185 mL) and treated with sodium azide (15.8 g, 243 mmol). The mixture was stirred at room temperature for 12 h, then heated to 45 °C and stirred for an additional 12 h. The mixture was added to methyl tert-butyl ether (400 mL) and washed with water (300 mL) and brine (300 mL). The aqueous phase was back-extracted with methyl tert-butyl ether (300 mL x 2). The combined organic phases were dried over anhydrous sodium sulfate and concentrated. The crude product was eluted with 50% ethyl acetate in n-heptane (100 mL) and passed through a short pad of silica gel (130 g). The filtrate was concentrated to give 7 as a light yellow foamy solid, which was used without purification.

[0191] Preparation of aminodiols 9 from azidolactone ((2S,3S,4S)-2-amino-5-azido-3-(4-(phenylethynyl)phenyl)pentane-l,4-diol) 7

[0192]

[0193] The above crude product 7 (26.0 g, 60.8 mmol) was added to ethanol (260 mL) to give a colorless solution. This was cooled in an ice bath and treated with sodium borohydride (2.76 g, 73.0 mmol). The mixture was stirred at this temperature for 2 h to give a white suspension. The ice bath was removed and the mixture was allowed to reach room temperature (rt), after which it was brought to 45 °C until gas evolution ceased and the mixture became homogeneous. The solution was treated with potassium carbonate (25.2 g, 182 mmol) and water (13 mL) and stirred at this temperature for 24 h. The mixture was concentrated and the residue was added to dichloromethane (390 mL). This was treated with celite (26 g) and filtered through a celite pad, rinsing with dichloromethane (260 mL x 2). The filtrate was concentrated to give an orange solid, which was eluted with 20% methanol in dichloromethane (adjusted with 1% ammonia solution, 2000 mL) and filtered through a silica gel pad (160 g). The filtrate was concentrated and the residue was crystallized (in isopropyl acetate / isopropanol = 3:1, the mother liquor was concentrated and further crystallized in acetonitrile, then ethyl acetate) to give 9 as a white solid (7.01 g). Another portion of 9 was obtained as a crude product in the mother liquor (7.84 g, based on 9.8 g of concentrate with ELSD showing 80% purity, 73% yield of 5 combined).

[0194] 1H NMR (400 MHz, MeOH-d4) δ 7.53-7.49 (m, 4H), 7.40-7.36 (m, 3H), 7.30 (d, J = 8.2 Hz, 2H), 4.31 (ddd, J = 9.8, 6.2, 2.7 Hz, 1H), 3.49-3.45 (m, 1H), 3.40 (dd, J = 10.6, 6.3 Hz, 1H), 3.33-3.32 (m, 1H), 3.29 (dd, J = 10.5, 7.4 Hz, 1H), 3.15 (dd, J = 12.7, 3.0 Hz, 1H), 3.03 (dd, J = 12.5, 6.6 Hz, 1H), 3.00 (dd, J = 9.7, 3.5 Hz, 1H); 13 C NMR (75 MHz, MeOH-d4) δ 138.4, 131.2, 131.1, 129.4, 128.1, 128.0, 123.1, 122.0, 88.9, 88.4, 70.8, 64.4, 55.6, 52.4, 50.1.

[0195] 9 One-pot N-nosylation and bis-O-mesylation; tandem N-nucleophilic substitution to azetidine (2-(((2S,3S,4R)-4-(azidomethyl)-1-((2-nitrophenyl)sulfonyl)-3-(4-(phenylethynyl)phenyl)azetidin-2-yl)methyl)isoindoline-1,3-dione) 12

[0196]

[0197] A suspension of 9 (2.00 g, 5.95 mmol) and triethylamine (4.97 mL, 35.7 mmol) in dichloromethane (20 mL) was cooled in an ice bath and treated with a solution of 2-nitrobenzenesulfonyl chloride (1.98 g, 8.92 mmol) in dichloromethane (10 mL) while maintaining an internal temperature below 6 °C. The mixture was stirred at this temperature for 30 minutes during which time it became homogeneous. The solution was then treated with methanesulfonyl chloride (1.39 mL, 17.8 mmol) and stirred at this temperature for 30 minutes. The reaction was quenched with aqueous sodium hydroxide (1 M, 100 mL) and the mixture was added to ethyl acetate (300 mL). The organic phase was separated, washed with brine (50 mL), and concentrated to yield a crude product consisting of bis-mesylate 11 and an aziridine intermediate.

[0198] The above crude product was added to N,N-dimethylformamide (20 mL) and treated with potassium carbonate (2.47 g, 17.8 mmol), potassium phthalimide (1.65 g, 8.92 mmol) and stirred at room temperature for 60 h. The reaction mixture was added to ethyl acetate (400 mL) and washed with water (100 mL), brine (100 mL) and concentrated. The residue was added to isopropanol (30 mL) and boiled to give a homogeneous solution, which was allowed to reach room temperature slowly with stirring, during which time the product precipitated. The product was filtered, washed with isopropanol (10 mL x 2) and dried under vacuum to give 12 as a beige solid (3.14 g, 83% yield).

[0199] 1 H NMR (400 MHz, CDC13) δ 8.15 (dd, J = 7.8, 1.5 Hz, 1H), 7.85 - 7.75 (m, 4H), 7.72 - 7.69 (m, 3H), 7.61 (d, J = 8.6 Hz, 2H), 7.57 - 7.54 (m, 2H), 7.45 (d, J = 8.2 Hz, 2H), 7.39 - 7.35 (m, 3H), 4.93 (dt, J = 8.2, 6.7 Hz, 1H), 4.55 (dt, J = 9.3, 3.9 Hz, 1H), 4.23 (dd, J = 14.4, 6.2 Hz, 1H), 3.79 (t, J = 8.6 Hz, 1H), 3.75 (dd, J = 14.4, 6.6 Hz, 1H), 3.71 (dd, J = 12.9, 5.1 Hz, 1H), 3.60 (dd, J = 12.8, 9.3 Hz, 1H); 13 C NMR (75 MHz, CDC13) δ 167.6, 149.3, 134.8, 134.0, 132.6, 132.2, 132.0, 131.8, 131.7, 131.6, 130.5, 128.4, 128.3, 127.4, 124.3, 123.5, 123.3, 123.1, 90.4, 88.8, 62.5, 61.9, 48.7, 42.4, 37.5.

[0200] (2-(((2S,3S,4R)-4-(azidomethyl)-l-(((4S,5R)-5-((R)-l,2-dihydroxyethyl)-2,2- dimethyl- 1,3 -dioxolan-4-yl)methyl)-3 -(4-(phenylethynyl)phenyl)azetidin-2- yl)methyl)isoindoline- 1,3 -dione) 15

[0201]

[0202] A clear, colorless solution of 12 (5.84 g, 9.23 mmol) and 1-dodecyl mercaptan (2.65 mL, 11.1 mmol) in tetrahydrofuran (70 mL) was cooled to an internal temperature of 4 °C in an ice bath. A solution of potassium tert-butoxide (1 M in THF, 11.1 mL, 11.1 mmol) was added dropwise while maintaining an internal temperature below 10 °C, during which time the mixture turned a deep red color. The ice bath was removed and the mixture was allowed to reach room temperature. The mixture was stirred at this temperature for 1 h, then quenched with aqueous sodium bicarbonate (100 mL) and taken up in ethyl acetate (200 mL). The two phases were separated and the aqueous phase was extracted with ethyl acetate (150 mL x 3). The combined organic phases were dried over anhydrous sodium sulfate and concentrated to give crude product 13 as a yellow gum.

[0203] Crude product 13 was combined with 14 (2.11 g, 11.1 mmol) and taken up in methanol (70 mL) to give a yellow solution, which was treated with acetic acid (2.64 mL, 46.2 mmol) and sodium cyanoborohydride (0.696 g, 11.1 mmol). The solution was stirred at room temperature for 24 h, then treated with additional acetic acid (2.64 mL, 46.2 mmol) and sodium cyanoborohydride (0.300 g, 4.78 mmol). After 12 h, a third portion of sodium cyanoborohydride (0.300 g, 4.78 mmol) was added and the mixture was stirred for an additional 6 h. The reaction mixture was taken up in ethyl acetate (200 mL) and washed with 1 M sodium hydroxide (100 mL). The aqueous phase was separated and back-extracted with ethyl acetate (200 mL). The combined organic phases were washed with brine (100 mL) and concentrated. The residue was filtered through a silica gel (140 g) column, first eluting with dichloromethane (700 mL) and then ethyl acetate (700 mL). The ethyl acetate filtrate was concentrated to give 15 (5.34 g, 93%) as a light yellow foamy solid, which was used without further purification.

[0204] Oxidative cleavage of the 1,2-diol of 15 to ((4S,5S)-5-(((2R,3S,4S)-2-(azidomethyl)-4-((1,3-dioxoisoindolin-2-yl)methyl)-3-(4-(phenylethynyl)phenyl)azetidin-1-yl)methyl)-2,2-dimethyl-1,3-dioxolane-4-carbaldehyde) 16

[0205]

[0206] A clear, colorless solution of 15 (5.34 g, 8.59 mmol) in tetrahydrofuran (64 mL) and water (6.4 mL) was treated with sodium periodate (2.76 g, 12.9 mmol). The mixture was stirred at room temperature for 2 h during which time it turned into a white, milky suspension. It was added to ethyl acetate (500 mL) and washed sequentially with aqueous sodium thiosulfate (50 mL) and brine (50 mL). The organic phase was separated and dried over anhydrous sodium sulfate. Concentration gave 16 as a white foamy solid which was used without purification.

[0207] Conversion of 16 to (2-(((3aR,6aR,7R,8S,10aS)-2,2-dimethyl-7-(4-(phenylethynyl)phenyl)octahydro-5H-azetepino[l,2-a][l,3]dioxolino[4,5-f][l,4]diazocino-8-yl)methyl)isoindoline-l,3-dione) 18 was accomplished using the azido-Wittig reaction and reduction sequentially

[0208]

[0209] The above crude product 16 was added to methanol (30 mL) to give a clear, colorless solution. This was added slowly to a stirred, white suspension of triphenylphosphine (2.70 g, 10.3 mmol) in methanol (50 mL) at room temperature over 8 h during which time the mixture turned into a colorless, homogeneous solution. The solution was stirred at this temperature for an additional 6 h, then acetic acid (2.46 mL, 43.0 mmol) and sodium cyanoborohydride (0.648 g, 10.3 mmol) were added. The mixture was stirred at this temperature for 4 h, then concentrated. The residue was added to ethyl acetate (400 mL) and washed with 1 M sodium hydroxide (40 mL) and brine (40 mL). The organic phase was dried over anhydrous sodium sulfate and concentrated to give crude 18 as a colorless gum.

[0210] Conversion of 18 to ((3aR,6aR,7S,8S,10aS)-8-((l,3-dioxoisoindolin-2-yl)methyl)-N-(4- methoxyphenyl)-2,2-dimethyl-7-(4-(phenylethynyl)phenyl)octahydro-5H-azetepino[l,2- a][l,3]dioxolino[4,5-f][l,4]diazocino-5-formamide) 19

[0211]

[0212] The above crude product 18 was taken up in dichloromethane (57 mL) and treated with 4-methoxyphenyl isocyanate (1.34 mL, 10.3 mmol). The mixture was kept at room temperature for 30 minutes and then concentrated. The residue was crystallized in a mixture of isopropanol / acetonitrile (1 :1, 100 mL) to give 19 as a white solid (1.60 g). The mother liquor was concentrated and purified using silica gel column chromatography (eluted with 50-60% ethyl acetate in heptane) to give additional 19 (1.0 g, 43% yield of 12 combined).

[0213] 1 H NMR (400 MHz, DMF-d7) δ 8.44 (s, 1H), 7.88 (s, 4H), 7.74 (d, J = 8.2 Hz, 2H), 7.64-7.61 (m, 4H), 7.51-7.44 (m, 3H), 7.37-7.33 (m, 2H), 6.87-6.83 (m, 2H), 4.50-4.47 (m, 1H), 4.34-4.29 (m, 1H), 4.08 (br dd, J = 16.0, 5.0 Hz, 1H), 3.97 (br dd, J = 16.0, 2.8 Hz, 1H), 3.87-3.65 (m, 6H), 3.75 (s, 3H), 3.52 (dd, J = 14.0, 4.6 Hz, 1H), 3.48 (s, 1H), 3.10 (br t, J = 2.1 Hz, 1H), 1.39 (s, 3H), 1.37 (s, 3H); 13 C NMR (75 MHz, DMF-d7) δ 168.9, 163.3, 157.5, 156.1, 138.5, 135.5, 135.0, 133.1, 132.6, 132.4, 132.3, 129.9, 129.8, 124.1, 124.1, 122.4, 122.1, 114.8, 108.1, 90.5, 90.5, 78.9, 77.4, 68.0, 66.5, 59.0, 56.1, 50.7, 47.4, 45.0, 39.7, 28.9, 26.3.

[0214] Hydrolysis of the phthalimide of 19 to ((3aR,6aR,7S,8S,10aS)-8-(aminomethyl)-N-(4-methoxyphenyl)-2,2-dimethyl-7-(4-(phenylethynyl)phenyl)octahydro-5H-azetidine[1,2-a][1,3]dioxolo[4,5-f][1,4]diazocin-5-formamide) 20

[0215]

[0216] A white suspension of 19 (2.30 g, 3.30 mmol) in methanol (23 mL) was treated with ethanolamine (2.00 mL, 33.0 mmol). The mixture was stirred at 55 °C for 12 h, then refluxed for 12 h during which time it turned into a homogeneous solution. It was treated with ethanolamine (1.50 mL, 24.8 mmol) and refluxed for 24 h. The solution was concentrated to give a colorless gum which was taken up in dichloromethane (300 mL), washed with (50 mL x 2), brine (50 mL), and dried over anhydrous sodium sulfate. It was concentrated to give crude product 20 as a white waxy solid which was used without purification.

[0217] Reductive amination and removal of the lactol of 20 to give ((3S,4R,8R,9S,10S)-10- ((dimethylamino)methyl)-3,4-dihydroxy-N-(4-methoxyphenyl)-9-(4-(phenylethynyl)phenyl)- 1,6-diazabicyclo[6.2.0]decane-6-carboxamide) 22

[0218]

[0219] The above crude product 20 was taken up in methanol (18.7 mL) to give a suspension which was treated with formaldehyde (37%, 3.69 mmol, 49.5 mmol), acetic acid (1.13 mL, 19.8 mmol), and sodium cyanoborohydride (0.622 g, 9.90 mmol). The mixture was stirred at room temperature for 2 h, then taken up in ethyl acetate (150 mL), washed with aqueous sodium bicarbonate (10 mL), brine (10 mL), dried over anhydrous sodium sulfate, and concentrated. The residue was passed through a pad of silica gel eluting with 15% methanol in dichloromethane, and concentrated to give crude product ((3aR,6aR,7S,8S,10aS)-8-((dimethylamino)methyl)-N-(4-methoxyphenyl)-2,2-dimethyl-7-(4- (phenylethynyl)phenyl)octahydro-5H-azetepino[l,2-a][l,3]dioxolo[4,5-f][l,4]diazocin-5- carboxamide) 21 as a colorless gum which was used without further purification.

[0220] The above crude product 21 was added to a mixture of tetrahydrofuran (14 mL) and 1 M hydrochloric acid (14 mL, 14 mmol) to give a colorless solution, which was stirred at 50 °C for 12 h. This was added to ethyl acetate (300 mL), washed with 1 M sodium hydroxide (50 mL), brine (50 mL), dried over anhydrous sodium sulfate, and concentrated. The residue was purified by silica gel column chromatography eluted with 20-30% methanol in dichloromethane (adjusted with 0.1% methanol solution of 7 M ammonia) to give 22 as a white waxy solid (0.86 g, 52%).

[0221] 1 H NMR (400 MHz, MeOH-d4) δ 7.56-7.51 (m, 6 H), 7.42-7.36 (m, 3 H), 7.16 (d, J = 9.0 Hz, 2 H), 6.84 (d, J = 8.9 Hz, 2 H), 4.19 (dd, J = 15.6, 6.6 Hz, 1 H), 4.14-4.10 (m, 1 H), 3.83-3.78 (m, 2 H), 3.76 (s, 3 H), 3.65 (dd, J = 14.4, 7.6 Hz, 1 H), 3.60 (br t, J = 7.1 Hz, 1 H), 3.40 (br t, J = 8.8 Hz, 1 H), 3.30 (d, J = 10.5 Hz, 1 H), 2.84 (dd, J = 13.5, 9.2 Hz, 1 H), 2.75 (dt, J = 15.2, 3.0 Hz, 1 H), 2.55 (dd, J = 13.3, 8.6 Hz, 1 H), 2.45 (dd, J = 13.3, 2.4 Hz, 1 H), 2.05 (s, 6 H); 13 C NMR (75 MHz, MeOH-d4) δ 160.2, 157.3, 138.7, 134.2, 132.7, 132.5, 132.3, 129.7, 129.6, 124.8, 123.5, 123.3, 115.1, 90.5, 90.2, 77.0, 74.0, 71.3, 66.8, 58.2, 57.7, 56.0, 53.0, 52.1, 46.9, 46.0

[0222] Synthesis of Route B

[0223] Reduction of 4-bromocinnamic acid methyl ester 1 to give 4-bromocinnamyl alcohol 23

[0224]

[0225] A 3 L three-necked round bottom flask was charged with methyl 4-bromocinnamate (1, 100 g, 414 mmol) and dichloromethane (1.1 L) to give a clear solution. This was cooled in a dry ice-acetone bath to give a milky mixture. This was treated with a solution of diisobutylaluminum hydride (25 wt% in toluene, 586 mL, 871 mmol) (pale green solution). The mixture was allowed to slowly reach -5 °C and was carefully quenched with a solution of potassium sodium tartrate tetrahydrate (351 g, 1.24 mol) in water (800 mL) in an ice bath. The mixture was stirred at room temperature overnight, treated with water (2 L), and extracted with methyl tert-butyl ether (1 L x 3). The combined organic phases were dried over anhydrous sodium sulfate and concentrated to give 4-bromocinnamyl alcohol (23, 87.5 g, 99%) as a white solid.

[0226] 1 H NMR (400 MHz, CDC13) δ 7.46 - 7.44 (m, 2H), 7.27 - 7.25 (m, 2H), 6.58 (d, J = 16.0 Hz, 1H), 6.37 (dt, J = 15.6, 5.5 Hz, 1H), 4.33 (dd, J = 5.8, 1.5 Hz, 2H)

[0227] Bromination of 4-bromocinnamyl alcohol 23 to give 4-bromocinnamyl bromide 24

[0228]

[0229] A 5 L three-necked round bottom flask was charged with 4-bromocinnamyl alcohol (23, 329 g, 1.54 mol) and diethyl ether (3 L). This was cooled to 5 °C using an ice bath, during which time the solution became slightly hazy. A solution of phosphorus tribromide in diethyl ether (72.6 mL, 772 mmol) was added dropwise to the mixture while maintaining the internal temperature below 12 °C, resulting in an approximately clear solution at the end of the addition. The mixture was stirred in an ice bath for 1 h, then quenched by slow addition of a solution of sodium bicarbonate (133 g, 1.57 mol) in water (1.5 L). The organic phase was separated and washed with brine (300 mL). The aqueous phase was extracted with methyl tert-butyl ether (1 L x 2). The combined organic phases were dried over anhydrous sodium sulfate and concentrated to give pure 24 (404 g, 95%) as a white solid.

[0230] 1 H NMR (400 MHz, CDC13) δ 7.48 - 7.45 (m, 2H), 7.25 - 7.24 (m, 2H), 6.59 (d, J = 15.6 Hz, 1H), 6.40 (dt, J = 15.6, 7.4 Hz, 1H), 4.15 (dt, J = 7.8, 0.7 Hz, 2H)

[0231] Preparation of ((S, E)-2-((tert-butylsulfinyl)imino)acetic acid ethyl ester) 25

[0232]

[0233] Zinc mediated crotylation of 25 to ((2S, 3S)-3-(4-bromophenyl)-2-(((S)- tert-butylsulfinyl)amino)4-pentenoic acid ethyl ester) 26

[0234]

[0235] A 5 L three necked round bottom flask was charged with 4-bromocinnamyl bromide (24, 175 g, 6363 mmol), 25 (87 g, 424 mmol) and N,N-dimethylformamide (1.3 L). The solution was sparged with nitrogen for 30 minutes while stirring. Zinc dust (55.4 g, 848 mmol) was added in portions while maintaining the internal temperature below 48 degrees. The mixture turned green initially and then brown towards the end of the addition. It was stirred at ambient temperature for 2 hours and then quenched with water (1.3 L). The mixture was filtered through a pad of celite, rinsing with methyl tert-butyl ether. The filtrate was added to water (1.3 L) and the aqueous phase was extracted with methyl tert-butyl ether (870 mL x 2). The combined organic phases were concentrated and the concentrate was filtered through a pad of celite, rinsing with a small amount of methyl tert-butyl ether. The filtrate was concentrated and the residue was purified by silica gel column chromatography (eluting with ethyl acetate in heptane) to give 26 as a light yellow oil (111 g, 65.2%).

[0236] 1 H NMR (400 MHz, CDC13) δ 7.44 - 7.40 (m, 2H), 7.05 - 7.03 (m, 2H), 6.05 - 5.96 (m, 1H), 5.17 - 5.11 (m, 2H), 4.20 - 4.12 (m, 3H), 3.91 (d, J = 9.4 Hz, 1H), 3.67 (t, J = 7.8 Hz, 1H), 1.25 (s, 3H)

[0237] Conversion of sulfilimine 26 to ((2S, 3S)-3-(4-bromophenyl)-2-((2- nitrophenyl)sulfinamido)4-pentenoic acid ethyl ester) 27

[0238]

[0239] A solution of 26 (2.48 g, 5.30 mmol) in tetrahydrofuran (21 mL) was treated with concentrated hydrogen chloride (37%, 2.18 mL, 26.5 mmol) and stirred at room temperature for 2 hours. The reaction was quenched with aqueous sodium bicarbonate (20 mL) followed by solid sodium bicarbonate until the mixture was no longer acidic. The mixture was extracted with methyl tert-butyl ether (200 mL x 3), dried over anhydrous sodium sulfate and concentrated to give a viscous yellow oil.

[0240] This was added to dichloromethane (16 mL), treated with 2-nitrobenzenesulfonyl chloride (1.29 g, 5.83 mmol) and triethylamine (1.11 mL, 7.95 mmol) to give an orange solution which was stirred at room temperature overnight. The mixture was added to methyl tert-butyl ether (200 mL) and washed with 1 M sodium hydroxide (30 mL). The aqueous phase was extracted with methyl tert-butyl ether (50 mL). The combined organic phases were dried over anhydrous sodium sulfate and concentrated. The residue was purified by column chromatography on silica gel eluting with 15-40% ethyl acetate in n-heptane to give 27 as a light yellow gum (2.29 g, 89%).

[0241] 1 H NMR (400 MHz, MeOH-d4) δ 7.50-7.32 (m, 3H), 7.23-7.19 (m, 2H), 7.10-7.07 (m, 2H), 5.97-5.88 (m, 1H), 5.01 (dd, J = 17.0, 1.0 Hz, 1H), 4.95 (dd, J = 10.1, 1.3 Hz, 1H), 4.06 (d, J = 10.5 Hz, 1H), 4.03-3.92 (m, 2H), 3.58 (t, J = 9.8 Hz, 1H), 1.76 (t, J = 7.0 Hz, 3H)

[0242] Iodolactonization and azido substitution of 27 to give (N-((3S,4S,5S)-5-(azidomethyl)-4-(4-bromophenyl)-2-oxotetrahydrofuran-3-yl)-2-nitrobenzenesulfonamide) 29

[0243]

[0244] A solution of 27 (10.0 g, 20.7 mmol) in acetonitrile (80 mL) and water (3.2 mL) was treated with iodine (10.5 g, 41.3 mmol) to give a deep red solution which was stirred at room temperature until all starting material was consumed. The reaction was quenched with excess aqueous sodium thiosulfate and stirred at room temperature until the mixture turned light yellow. The mixture was taken up in methyl tert-butyl ether, washed with brine, dried over anhydrous sodium sulfate and concentrated to give the crude product (N-((3S,4S,5S)-4-(4-bromophenyl)-5-(iodomethyl)-2- oxotetrahydrofuran-3-yl)-2-nitrobenzenesulfonamide) 28 (12 g) as a white solid.

[0245] 1 H NMR (400 MHz, CDC13) δ 7.89 (dd, J = 8.1, 1.4 Hz, 1H), 7.81 (dd, J = 8.0, 1.4 Hz, 1H), 7.72 (dt, J = 7.8, 1.5 Hz, 1H), 7.62 (dt, J = 7.8, 1.2 Hz, 1H), 7.44 - 7.41 (m, 2H), 7.15 - 7.12 (m, 2H), 6.25 (d, 9.0 Hz, 1H), 4.81 (dd, J = 12.1, 9.0 Hz, 1H), 4.27 - 4.22 (m, 1H), 3.48 - 3.41 (m, 2H), 3.24 (dd, J = 11.9, 4.9 Hz, 1H)

[0246] The crude product 28 was taken up in N,N-dimethylformamide (65 mL) and treated with sodium azide (2.02 g, 31.0 mmol) to give a yellow suspension which was stirred at room temperature overnight. The mixture was taken up in methyl tert-butyl ether, washed with water, brine, dried over anhydrous sodium sulfate and concentrated. The residue was purified using silica gel column chromatography (eluting with ethyl acetate in heptane) to give 29 (7.90 g, 77%) as a white solid.

[0247] 1 H NMR (400 MHz, CDC13) δ 7.89 (dd, J = 8.1, 1.4 Hz, 1H), 7.81 (dd, J = 8.0, 1.4 Hz, 1H), 7.72 (dt, J = 7.8, 1.5 Hz, 1H), 7.62 (dt, J = 7.8, 1.2 Hz, 1H), 7.44 - 7.41 (m, 2H), 7.15 - 7.12 (m, 2H), 6.25 (d, 9.0 Hz, 1H), 4.81 (dd, J = 12.1, 9.0 Hz, 1H), 4.27 - 4.22 (m, 1H), 3.48 - 3.41 (m, 2H), 3.24 (dd, J = 11.9, 4.9 Hz, 1H)

[0248] Reduction of 29 to give (N-((2S,3S,4S)-5-azido-3-(4-bromophenyl)-1,4- dihydroxypentan-2-yl)-2-nitrobenzenesulfonamide) 30

[0249]

[0250] A yellow solution of 29 (9.10 g, 18.3 mmol) in ethanol (80 mL) was treated with sodium borohydride (1.04 g, 27.5 mmol) in portions, during which the mixture turned dark purple. The reaction was stirred at room temperature for 1 h, then it was quenched with 1 M HCI. The mixture was added to methyl tert-butyl ether, washed with water, brine, dried over anhydrous sodium sulfate and concentrated. The residue was purified using silica gel column chromatography (eluting with 50-80% ethyl acetate in heptane) to give 30 as a white solid (8.20 g, 89%).

[0251] 1 H NMR (400 MHz, CDC13) δ 8.17 - 8.15 (m, 1H), 7.92 - 7.89 (m, 1H), 7.80 - 7.75 (m, 2H), 7.48 (d, J=8.6 Hz, 2H), 7.10 (d, J=8.2 Hz, 2H), 5.45 (d, J=9.0 Hz, 1H), 4.41 - 4.37 (m, 1H), 4.16 - 4.11 (m, 1H), 3.72 (br s, 1H), 3.44 (dd, J=11.4, 5.5 Hz, 1H), 3.30 (dd, J=11.3, 7.0 Hz, 1H), 3.23 (dd, J=12.9, 2.7 Hz, 1H), 3.00 - 2.91 (m, 2H)

[0252] Conversion of 30 to azetidine (2-(((2S,3S,4R)-4-(azidomethyl)-3-(4- bromophenyl)-1-((2-nitrophenyl)sulfonyl)azetidin-2-yl)methyl)isoindoline-1,3-dione) 32 by bis-mesylation and tandem N-nucleophilic substitution

[0253]

[0254] A solution of 30 (5.37 g, 10.7 mmol) and triethylamine (5.98 mL, 42.9 mmol) in dichloromethane (50 mL) was cooled to 0 °C and treated dropwise with methanesulfonyl chloride (2.08 mL, 26.8 mmol). The light yellow turbid mixture was stirred at this temperature for 2 h, then quenched with aqueous sodium bicarbonate. The mixture was extracted with ethyl acetate, washed with water and brine. The organic phase was dried over anhydrous sodium sulfate and concentrated to yield a crude product containing 31 and an aziridine intermediate.

[0255] The residue was taken up in N,N-dimethylformamide (35 mL), treated with potassium carbonate (4.45 g, 32.2 mmol), potassium phthalimide (2.39 g, 12.9 mmol), and stirred at room temperature for 84 h. The mixture was taken up in ethyl acetate, washed with water, brine, dried over anhydrous sodium sulfate, and concentrated. The residue was purified using silica gel column chromatography (eluting with ethyl acetate in heptane) to yield 32 as a white solid (4.92 g, 75%).

[0256] 1 H NMR (400 MHz, CDC13) δ 8.14 (dd, J = 7.9, 1.6 Hz, 1H), 7.83 - 7.70 (m, 7H), 7.58 (d, J = 8.6 Hz, 2H), 7.33 (d, J = 8.2 Hz, 2H), 4.91 (dd, J = 14.9, 6.7 Hz, 1H), 4.56 - 4.50 (m, 1H), 4.18 (dd, J = 17.7, 6.0 Hz, 1H), 3.77 - 3.68 (m, 3H), 3.55 (dd, J = 12.7, 9.6 Hz, 1H)

[0257] Conversion of 32 to (2-(((2S,3S,4R)-4-(azidomethyl)-3-(4-bromophenyl)-1-(((4S,5R)-5-((R)-1,2-dihydroxyethyl)-2,2-dimethyl-1,3-dioxolan-4-yl)methyl)azetidin-2-yl)methyl)isoindoline-1,3-dione) 35 by deprotection and reductive amination

[0258]

[0259] A solution of 32 (1.35 g, 2.21 mmol) and 1-dodecyl mercaptan (0.635 mL, 2.65 mmol) in tetrahydrofuran (10 mL) was treated dropwise with a solution of potassium tert-butoxide (1 M in tetrahydrofuran, 2.65 mL, 2.65 mmol) at room temperature and then stirred for 5 h. The mixture was added to ethyl acetate, washed with brine, dried over anhydrous sodium sulfate and concentrated to give the crude product (2-(((2S,3S,4R)-4-(azidomethyl)-3-(4-bromophenyl)azetidin-2-yl)methyl)isoindoline- 1,3-dione) 33 as a yellow gum.

[0260] A mixture of the crude product 33 (0.469 g, 1.10 mmol) and ((3aR,6R,6aR)-6- (hydroxymethyl)-2,2-dimethyltetrahydrofuro[3,4-d][l,3]dioxol-4-ol) 34 (0.29 g, 1.53 mmol) was added to methanol (5 mL) and treated with acetic acid (0.315 mL, 5.50 mmol), sodium cyanoborohydride (0.104 g, 1.65 mmol) and stirred at room temperature until the reaction was complete. The mixture was added to ethyl acetate, washed with 1 M sodium hydroxide, brine, dried over anhydrous sodium sulfate and concentrated. The residue was purified using silica gel column chromatography (eluted with methanol in dichloromethane) to give 35 (365 mg, 55%) as a colorless oil.

[0261] 1 H NMR (400 MHz, CDC13) δ 7.77 - 7.74 (m, 2H), 7.71 - 7.67 (m, 2H), 7.52 (d, J = 8.2 Hz, 2H), 7.19 (d, J = 8.6 Hz, 2H), 6.11 (br s, 1H), 4.53 - 4.48 (m, 1H), 4.31 (dd, J = 9.3, 6.2 Hz, 1H), 3.93 - 3.75 (m, 7H), 3.58 (dd, J = 13.9, 7.3 Hz, 1H), 3.51 - 3.46 (m, 1H), 3.32 - 3.24 (m, 2H), 2.77 (dd, J = 12.5, 3.9 Hz, 1H), 2.49 (br s, 1H), 1.41 (s, 3H), 1.33 (s, 3H)

[0262] Reduction of aminated 33 with ((3aR,6aR)-2,2-dimethyltetrahydrofuran[3,4- d][l,3]dioxol-4-ol) 36 gave (2-(((2S,3S,4R)-4-(azidomethyl)-3-(4-bromophenyl)-l-(((4S,5R)-5- (hydroxymethyl)-2,2-dimethyl-l,3-dioxolan-4-yl)methyl)azetidin-2-yl)methyl)isoindoline- 1,3-dione) 37

[0263]

[0264] Crude product 35 (2.72 g, 6.38 mmol) and 36 (1.53 g, 9.57 mmol) were added to methanol (40 mL), acetic acid (1.83 mL, 31.9 mmol) and treated with sodium cyanoborohydride (0.601 g, 9.57 mmol). The mixture was stirred at room temperature until the reaction was complete. The mixture was added to methyl tert-butyl ether (500 mL), washed with 1 M sodium hydroxide (50 mL) and brine (50 mL). The aqueous phase was back-extracted with methyl tert-butyl ether (100 mL x 2). The combined organic phases were dried over anhydrous sodium sulfate and concentrated. The residue was purified by silica gel column chromatography eluting with methanol in dichloromethane, and purified by silica gel column chromatography (70 mM ammonia in methanol) to give 37 (2.34 g, 64%) as a white foamy solid.

[0265] 1 H NMR (400 MHz, CDC13) δ 7.75 - 7.71 (m, 2H), 7.68 - 7.64 (m, 2H), 7.48 - 7.45 (m, 2H), 7.23 - 7.21 (m, 2H), 4.43 - 4.34 (m, 2H), 4.01 (br s, 1H), 3.81 - 3.66 (m, 6H), 3.50 (dd, J = 13.7, 6.6 Hz, 1H), 3.42 (dd, J = 12.7, 6.5 Hz, 1H), 3.21 (dd, 12.7, 6.5 Hz, 1H), 3.08 (dd, 12.9, 7.8 Hz, 1H), 2.76 (dd, J = 12.9, 5.1 Hz, 1H), 1.41 (s, 3H), 1.31 (s, 3H)

[0266] Oxidative cleavage of 35 gave ((4S,5S)-5-(((2R,3S,4S)-2-(azidomethyl)-3-(4- bromophenyl)-4-((l,3-dioxoisoindolin-2-yl)methyl)azetidin-l-yl)methyl)-2,2-dimethyl- 1,3-dioxolan-4-carbaldehyde) 38

[0267]

[0268] A solution of 35 (2.73 g, 4.55 mmol) in tetrahydrofuran (33 mL) and water (3.6 mL) was treated with sodium periodate (1.46 g, 6.82 mmol) and stirred at room temperature for 2 hours to form a white suspension. The mixture was added to methyl tert-butyl ether (500 mL) and washed with aqueous sodium thiosulfate (100 mL) and aqueous sodium bicarbonate (100 mL). The combined aqueous phases were back-extracted with methyl tert-butyl ether (150 mL x 2). The combined organic phases were dried over anhydrous sodium sulfate and concentrated to give 38 as a colorless gum which was used without purification.

[0269] 1 H NMR (400 MHz, CDC13) δ 9.79 (d, J = 2.7 Hz, 1H), 7.78-7.75 (m, 2H), 7.71-7.68 (m, 2H), 7.52-7.49 (m, 2H), 7.31-7.29 (m, 2H), 4.54-4.51 (m, 1H), 4.47-4.44 (m, 2H), 3.79-3.3.61 (m, 4H), 3.46-3.40 (m, 2H), 3.21-3.19 (m, 1H), 2.96 (dd, J = 13.7, 4.7 Hz, 1H), 2.80 (dd, J = 13.7, 5.5 Hz, 1H), 1.60 (s, 3H), 1.41 (s, 3H)

[0270] Oxidation of 37 to give 38

[0271]

[0272] A solution of 37 (900 mg, 1.58 mmol) in dichloromethane (10 mL) was treated with Dess Martin periodinane (803 mg, 1.89 mmol) and stirred at room temperature for 3 hours. The mixture was added to ethyl acetate, washed with aqueous sodium thiosulfate, 1 M sodium hydroxide, brine, dried over anhydrous sodium sulfate, and concentrated to give 38 as a colorless gum which was used without purification.

[0273] Aza-Wittig reaction of 38 and subsequent reduction to give (2-(((3aR,6aR,7R,8S,10aS)-7-(4-bromophenyl)-2,2-dimethyloctahydro-5H-azetidine[1,2-a][1,3]dioxolo[4,5-f][1,4]diazocin-8-yl)methyl)isoindoline-1,3-dione) 40

[0274]

[0275] To a suspension of triphenylphosphine (1.79 g, 6.82 mmol) in methanol (13 mL) was slowly added a solution of crude 38 in methanol (39 mL) and tetrahydrofuran (7.8 mL) over 12 hours to give a clear solution. After an additional 3 hours, the solution was treated with acetic acid (0.78 mL, 13.6 mmol) and sodium cyanoborohydride (0.343 g, 5.46 mmol) and stirred for 3 hours. The mixture was taken up in methyl tert-butyl ether, washed with 1 M sodium hydroxide, brine, dried over anhydrous sodium sulfate, and concentrated. The residue was purified by column chromatography on silica gel eluting with ethyl acetate to give 40 as a white solid (1.88 g, 79%).

[0276] 1 H NMR (400 MHz, CDC13) δ 7.81 - 7.77 (m, 2H), 7.71 - 7.64 (m, 2H), 7.46 - 7.44 (m, 2H), 7.40 - 7.38 (m, 2H), 4.87 (br s, 3H), 4.39 - 4.34 (m, 1H), 4.28 - 4.24 (m, 1H), 3.75 (dd, J = 14.0, 5.5 Hz, 1H), 3.70 - 3.65 (m, 1H), 3.60 - 3.55 (m, 2H), 3.47 (dd, J = 14.2, 5.3 Hz, 1H), 3.28 (dd, J = Hz, 1H), 3.27 (dd, J = 14.6, 9.8 Hz, 1H), 3.08 (dd, J = 14.7, 2.2 Hz, 1H), 2.90 (dd, J = 13.2, 4.3 Hz, 1H), 2.79 (dd, J = 13.6, 8.6 Hz, 1H), 2.71 - 2.60 (m, 2H), 1.36 (s, 3H), 1.32 (s, 3H)

[0277] Conversion of 40 to ((3aR,6aR,7S,8S,10aS)-7-(4-bromophenyl)-8-((1,3-dioxoisoindolin-2-yl)methyl)-N-(4-methoxyphenyl)-2,2-dimethyloctahydro-5H-azetidine[1,2-a][1,3]dioxolo[4,5-f][1,4]diazocin-5-formamide) 41

[0278]

[0279] A solution of 40 (70 mg, 0.133 mmol) in dichloromethane (1.5 mL) was treated with 4-methoxyphenyl isocyanate (0.026 mL, 0.199 mmol), triethylamine (0.028 mL, 0.199 mL) and kept at room temperature for 2 hours. The mixture was concentrated and the residue was purified using silica gel column chromatography (eluted with ~ 60% ethyl acetate in heptane) to yield 41 (67 mg, 75%) as a white solid.

[0280] 1 H NMR (400 MHz, CDC13) δ 8.35 (s, 1H), 7.85-7.80 (m, 2H), 7.73-7.69 (m, 2H), 7.51-7.45 (m, 4H), 7.23-7.19 (m, 2H), 6.85-6.80 (m, 2H), 4.38 (d, J = 16.8 Hz, 1H), 4.29 (br s, 2H), 4.16-4.10 (m, 1H), 3.86-3.77 (m, 2H), 3.77 (s, 3H), 3.65-3.47 (m, 4H), 2.79-2.73 (m, 1H), 2.64-2.61 (m, 2H), 1.44 (s, 3H), 1.41 (s, 3H)

[0281] Hydrolysis of the propionyl ketone 41 to yield ((3S,4R,8R,9S,10S)-9-(4-bromophenyl)-10-((1,3-dioxoisoindolin-2-yl)methyl)-3,4-dihydroxy-N-(4-methoxyphenyl)-1,6-diazabicyclo[6.2.0]decane-6-carboxamide) 42

[0282]

[0283] A solution of 41 (5.0 mg, 0.0074 mmol) in tetrahydrofuran (1 mL) and 1 M HCI (1 mL) was stirred at 50 °C for 3 hours. The solution was concentrated and the residue was purified by reverse phase preparative HPLC to yield 42 (3.8 mg, 81%) as a white solid.

[0284] 1H NMR (400 MHz, CD3OD) δ 7.79-7.73 (m, 4H), 7.52-7.46 (m, 4H), 7.11-7.07 (m, 2H), 6.80-6.76 (m, 2H), 4.14 (dd, J = 15.5, 6.5 Hz, 1H), 4.08-4.07 (m, 1H), 3.82-3.68 (m, 4H), 3.71 (s, 3H), 3.33-3.27 (m, 2H), 2.82-2.73 (m, 2H), 2.82-2.73 (m, 2H), 2.67-2.63 (m, 1H)

[0285] 42may be converted to compound 22 according to the foregoing procedures. See, e.g., WO 2018 / 175385 at pages 53-55, which is incorporated by reference herein in its entirety. The process is shown in brief as follows:

[0286]

[0287] The structures of compounds 5 and 32 were verified by X-ray crystallography. Figure 1 and Figure 2 ORTEP projections of compounds 5 and 32, respectively, are provided below. ORTEP is an acronym for Oak Ridge Thermal Ellipsoid Plot, which is a representation of a molecular structure as determined by X-ray diffraction.

[0288] Other procedures that can be used in combination with the foregoing procedures or independently are shown below.

[0289] Hydrolysis of the o-nitrophenyl sulfonamide of 12 using mercaptoacetic acid to generate 13

[0290]

[0291] Into a reactor was charged 12 (1.0 w / w, 1.0 eq), methanol (12 v / w) and tetrahydrofuran (4 v / w) at room temperature. Mercaptoacetic acid (0.221 v / w, 0.291 w / w, 2.0 eq) and potassium carbonate (0.874 w / w, 4.0 eq) were added in one portion each. The mixture was heated to an internal temperature of 50 °C and stirred for 34 h. The complete consumption of 12 was monitored using LCMS / UV of an aliquot of the reaction. The reaction mixture was poured into a separate vessel for extraction with ethyl acetate (25 v / w) and water (18 v / w). The aqueous phase was back-extracted twice with ethyl acetate (12 v / w). The organic phases were combined and washed with aqueous sodium bicarbonate (12 v / w) followed by 50% brine (12 v / w). The organic phase was dried over anhydrous sodium sulfate. The organic phase was filtered and concentrated using a rotary evaporator under house vacuum (T bath = 37 °C) to yield crude 13 as a yellow gum (~0.8 v / w, quant.).

[0292] Reaction volume: 17 v / w

[0293] Work-up volume: 65 v / w

[0294] Expected yield (%): quantitative

[0295] Maximum scale: 20 g of 12

[0296] 1 H NMR (400 MHz, CDC13) 7.84 - 7.82 (m, 2 H), 7.72 - 7.67 (m, 2 H), 7.62 - 7.52 (m, 6 H), 7.39 - 7.32 (m, 3 H), 4.50 (dt, J=7.6, 4.5 Hz, 1 H), 4.25 (dd, J=14.1, 7.0 Hz, 1 H), 3.91 (dd, J=14.3, 7.8 Hz, 1 H), 3.79 (t, J=7.6 Hz, 1 H), 3.53 (dd, J=14.2, 4.4 Hz, 1 H), 3.35 (dd, J=12.6, 7.1 Hz, 1 H), 3.20 (dd, J=12.6, 6.6 Hz, 1 H); 13 C NMR (75 MHz, CDC13) 168.2, 135.6, 134.3, 134.0, 132.0, 131.6, 131.6, 130.6, 128.4, 128.3, 123.3, 122.5, 89.9, 89.2, 57.5, 57.2, 52.0, 46.7, 40.2

[0297] Reduction of aminated 13 using 14 to generate 15 HCI (HCI salt of 15)

[0298]

[0299] The reactor was charged with crude product 13 (prepared as described above, 1.0 w / w, 1.0 eq), 14 (0.850 w / w, 2.0 eq) and ethanol (10 v / w). To this mixture was added, at room temperature, in one portion, successively, acidic acid (0.640 v / w, 0.671 w / w, 5.0 eq) and sodium cyanoborohydride (0.281 w / w, 2.0 eq) 1 The mixture was stirred at room temperature for 12-18 hours. The complete consumption of 13 was monitored using an aliquot of the reaction by LCMS / UV. The reaction was quenched using saturated aqueous sodium bicarbonate solution (18 v / w) followed by ethyl acetate (35 v / w) 2 The mixture was stirred at room temperature for 10 minutes. The two phases were separated using a separate vessel and the aqueous phase was back extracted twice with ethyl acetate (15 v / w). The organic phases were combined, washed with brine (18 v / w) and dried over anhydrous sodium sulfate. The organic phase was filtered and concentrated using a rotary evaporator under a clean vacuum (T bath = 37°C). The residue was taken up in ethyl acetate (35 v / w) and filtered through a plug of silica gel to remove insoluble material. The clear filtrate was cooled in an ice bath and 4M HCI-dioxane solution (0.071 v / w, 1.05 eq) was added slowly over 10 minutes 3 The white suspension was stirred in an ice bath for 10 minutes and then stirring was stopped and the mixture was allowed to stand for 20 minutes to allow the white solid to precipitate 4 The mixture was filtered in the order of clear supernatant first and then the suspension of white solid. The filter cake was washed with ethyl acetate. The filter cake was dried in a clean vacuum oven at 40°C to yield 15 HCI as a white solid (0.813 w / w, 55%).

[0300] Expected yield (%): > 55%

[0301] Maximum: 20 g of 12

[0302] 1H NMR (400 MHz, MeOH-d4) 7.83-7.78 (m, 4H), 7.57-7.51 (m, 6H), 7.40-7.38 (m, 3H), 5.420 8 (dt, J = 9.7, 6.6 Hz, 1H), 4.93-4.85 (m, 1H), 4.59 (dd, 8.5, 6.5 Hz, 1H), 4.45-4.34 (m, 2H), 4.21 (dd, J = 8.7, 6.4 Hz, 1H), 4.14-3.94 (m, 3H), 3.76 (d, J = 9.0 Hz, 1H), 3.69-3.58 (m, 4H), 1.48 (s, 3H), 1.08 (s, 3H); 13 C NMR (75 MHz, MeOH-d4) 168.9, 135.7, 133.1, 133.1, 132.6, 132.5, 131.9, 131.8, 129.8, 129.6, 125.2, 124.4, 124.2, 111.6, 91.5, 89.2, 77.5, 74.4, 71.0, 69.2, 68.9, 65.0, 59.3, 43.7, 37.5, 28.1, 25.2

[0303] Oxidative cleavage of 1,2-diol 15· HCI using sodium periodate

[0304]

[0305] Compound 15· HCI (1.0 w / w, 1.0 eq), tetrahydrofuran (15 v / w, 13.2 w / w), and water (5 v / w, 5 w / w) were charged to a reactor. Sodium periodate (0.650 w / w, 2.0 eq) was added in one portion. The mixture was stirred at room temperature for 1-2 hours. The complete consumption of 15 was monitored using an aliquot of the reaction mixture by LCMS / UV. The mixture was poured into ethyl acetate (36 v / w, 32.4 w / w) and washed with aqueous sodium bicarbonate (12 v / w) followed by brine (12 v / w). The organic phase was dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated using a rotary evaporator at a sweeping vacuum (T bath = 37 °C) to yield crude product 16 as a colorless oil (~0.9 w / w, 1.0 eq).

[0306] Expected yield (%): 100%

[0307] Maximum amount: 8.3 g of 15· HCI

[0308] 1H NMR (400 MHz, CDC13) 9.82 (d, J = 2.8 Hz, 1H), 7.79-7.76 (m, 2H), 7.71-7.67 (m, 2H), 7.58-7.53 (m, 4H), 7.44-7.42 (m, 2H), 7.39-7.35 (m, 3H), 4.55 (dd, J = 11.9, 5.8 Hz, 1H), 4.48 (dd, J = 7.2, 2.8 Hz, 1H), 3.82-3.67 (m, 3H), 3.50-3.41 (m, 2H), 3.27-3.22 (m, 1H), 2.98 (dd, J = 13.6, 4.7 Hz, 1H), 2.82 (dd, J = 13.6, 5.7 Hz, 1H), 1.61 (s, 3H), 1.42 (s, 3H); 13 CNMR (75 MHz, CDC13) 199.9, 167.8, 135.3, 134.0, 131.8, 131.7, 131.6, 130.6, 128.3, 128.2, 123.3, 123.2, 122.4, 110.9, 89.8, 89.2, 81.4, 66.7, 66.4, 56.9, 50.2, 44.2, 38.1, 27.3, 22.7

[0309] Tandem Staudinger / aza-Wittig / reduction converts 16 to 18 HCI

[0310]

[0311] Triphenylphosphine (0.128 w / w, 1.2 eq) and ethanol (7 v / w, 5.52 w / w) were charged to the reactor. To this mixture was added slowly a solution of crude product 16 (as prepared above, 1.0 w / w, 1.0 eq) in ethanol (10 v / w, 7.89 w / w) and tetrahydrofuran (5 v / w, 4.40 w / w) over 1.5 hours at room temperature. The reaction mixture was further stirred for 12 hours at room temperature and monitored for complete consumption of 16 using an aliquot of the reaction mixture by LCMS / UV. Sodium cyanoborohydride (0.128 w / w, 1.2 eq) and acetic acid (0.291 v / w, 0.306 w / w, 3.0 eq) were added in one portion each at room temperature 1The mixture was stirred at this temperature for 0.5-1 h and monitored for complete consumption of the imine intermediate (not shown) using an aliquot of the reaction mixture by LCMS / UV. The reaction was quenched with aqueous sodium bicarbonate solution (30 v / w) and extracted with ethyl acetate (30 v / w). The aqueous phase was further extracted twice with ethyl acetate (12 v / w). The organic phases were combined, washed with brine (12 v / w) and dried over anhydrous sodium sulfate. The organic phase was filtered and concentrated using a rotary evaporator under a sweeping vacuum (T bath = 37 °C) for 10 min. The resulting white suspension was further stirred in an ice bath for 10 min, then stirring was stopped and the mixture was allowed to stand still for 20 min to allow the white solid to precipitate 2 . The mixture was filtered and the filter cake was washed with ethyl acetate. The filter cake was dried in a sweeping vacuum oven at 40 °C to yield 18»HCl as a white solid (0.81 w / w, 82%).

[0312] Expected yield (%): 80%

[0313] Maximum amount: 8.3 g of 18»HCl

[0314] 1) Additional spectral data

[0315]

[0316] Compound 18: 1 H NMR (400 MHz, CDC13) 7.82 - 7.78 (m, 2 H), 7.71 - 7.65 (m, 2 H), 7.55 - 7.49 (m, 6 H), 7.38 - 7.31 (m, 3 H), 4.40 - 4.35 (m, 1 H), 4.23 - 4.19 (m, 1 H), 3.79 (dd, J=14.2, 5.5 Hz, 1 H), 3.70 (dd, J=11.7, 6.0 Hz, 1 H), 3.51 (dd, J=14.2, 5.2 Hz, 1 H), 3.28 (dd, J=14.6, 8.5 Hz, 1 H), 3.09 (dd, J=14.6, 2.4 Hz, 1 H), 2.87 - 2.68 (m, 3 H), 2.59 (br d, J=13.3 Hz, 1 H), 1.74 (br s, 1 H), 1.39 (s, 3 H), 1.33 (s, 3 H); 13C NMR (75 MHz, CDC13) 167.9, 136.6, 133.9, 131.9, 131.5, 131.2, 130.8, 128.3, 128.1, 123.3, 123.2, 121.8, 106.8, 89.5, 89.3, 77.7, 68.2, 65.1, 57.7, 48.7, 45.5, 44.7, 38.5, 27.8, 25.1

[0317]

[0318] Compound 21: 1 H NMR (400 MHz, CDC13) 8.32 (br s, 1H), 7.56-7.53 (m, 2H), 7.52-7.50 (m, 2H), 7.45-7.43 (m, 2H), 7.39-7.33 (m, 3H), 7.25-7.21 (m, 2H), 6.85-6.82 (m, 2H), 4.36 (dd, J = 16.8, 2.7 Hz, 1H), 4.30-4.28 (m, 1H), 4.23-4.18 (m, 1H), 4.13-4.09 (m, 1H), 3.78 (s, 3H), 3.69-3.65 (m, 1H), 3.63-3.54 (m, 3H), 2.79 (br d, J = 8.0 Hz, 2H), 2.63 (dd, J = 13.7, 10.5 Hz, 1H), 2.44 (dd, J = 13.3, 8.2 Hz, 1H), 2.34 (dd, J = 13.1, 3.7 Hz, 1H), 2.05 (s, 6H), 1.52 (s, 3H), 1.44 (s, 3H); 13 C NMR (75 MHz, CDC13) 167.9, 136.6, 133.9, 131.9, 131.5, 131.2, 130.8, 128.3, 128.1, 123.3, 123.2, 121.8, 106.8, 89.5, 89.3, 77.7, 68.2, 65.1, 57.7, 48.7, 45.5, 44.7, 38.5, 27.8, 25.1

[0319] While the embodiments of the application have been described with respect to specific example embodiments and examples, it is to be understood that the embodiments disclosed herein are not intended to be limiting, and that variations and modifications can be effected without departing from the spirit and scope of the application as set forth in the following claims.

Claims

1. A method of forming a solid compound of Formula I: ###0001### wherein, R1 is ###0002### R2 is C(O)R3; and P1 is -C(O)CF3; the method comprising: reacting a reactant of Formula II: ###0003### with lithium diisopropylamide in the presence of ZnCl2, to form a compound of Formula III: ###0004### and reducing the compound of Formula III to form a compound of Formula I.

2. A method of forming a compound of Formula IV, ###0005### wherein, R1 is ###0006### P1 is -H or a nitrogen protecting group selected from the group consisting of 2-nitrobenzenesulfonyl and 4-nitrobenzenesulfonyl; and NP2 forms: ###0007### the method comprising: forming a compound of Formula I from the method of claim 1, ###0008### and forming a lactone of Formula V from the compound of Formula I, ###0009### wherein R2 is C(O)R3; and P1 in Formula I and Formula V is selected from the group consisting of 9-fluorenylmethyl carbamate and -C(O)CF3; reducing the lactone of Formula V to a compound of Formula VI, ###0010### wherein P1 in Formula VI is selected from the group consisting of 9-fluorenylmethyl carbamate, -C(O)CF3, 2-nitrobenzenesulfonyl and 4-nitrobenzenesulfonyl, and H; and converting the two alcohol groups of Formula VI to mesylate leaving groups to form an intermediate of Formula VII or Formula VIIb, ###0011### which reacts with phthalimide to yield a compound of Formula IV: ###0012### wherein P1 in Formula VII and Formula VIIb is selected from the group consisting of 2-nitrobenzenesulfonyl and 4-nitrobenzenesulfonyl.

3. The method of claim 2, wherein R1 is ###0013### the lactone of Formula V is formed by reacting the compound of Formula I with a halogen in a polar solvent. ； 4. The method of claim 3, wherein the halogen is I2 and the polar solvent is an aqueous mixture of CH3CN. R3 is -O - and a cationic counterion is associated with the ion of formula I; 5. The method of claim 3, wherein the lactone of Formula V is formed by reacting the compound of Formula I with I2 in a polar solvent to form a first product having the following formula: ###0014### reacting the first product with NaN3 to form a compound of Formula V, wherein P1 in the formula of the first product is selected from the group consisting of 9-fluorenylmethyl carbamate and -C(O)CF3.

6. The method of claim 2, wherein the reducing is performed with NaBH4.

7. The method of claim 2, wherein P1 in Formula IV, Formula VII and Formula VIIb is -H. and, by crystallization with (R)-(-)-1-phenylethylamine. R racemic mixture is resolved by crystallization with (R)-(-)-1-phenylethylamine.

10. A method of preparing a compound of the following structure, ###0015### wherein, R1 is ###0016### R6 and R7 are independently the same or different and are selected from the group consisting of -H, -OH, alkyl, -Oalkyl, or wherein R6 and R7 together with the atoms to which they are attached form a ring; R8 and R9 are independently the same or different and are selected from the group consisting of -H, -alkyl, -C(O)alkyl, -S(O)2alkyl, or R8 and R9 together with the N to which they are attached form a monocyclic or bicyclic ring system; wherein the alkyl has 1 to 24 carbons, the aryl is a 6 to 14 membered monocyclic, bicyclic or tricyclic aromatic hydrocarbon ring system, and the heteroaryl is a 5 to 14 membered aromatic heterocycle and has at least one heteroatom selected from the group consisting of nitrogen, oxygen and sulfur; the method comprising reacting a compound of Formula IV formed from the method of claim 2 to obtain a compound of Formula IV: ###0017### wherein P1 of Formula IV is -H; and wherein 11. The method of claim 10, wherein the compound of Formula IV is reacted with a substituted gamma-hydroxyaldehyde to form a compound of Formula VIII, ###0018### wherein the substituted gamma-hydroxyaldehyde is ###0019### and the compound of Formula VIII is prepared via the following intermediate: ###0020### ； ​ ​ ； ​ ​ ​ ​ R3 is -OH, -Oalkyl having 1 to 2 carbon atoms, or -O - ; wherein when R3is -O - the cation is associated with an ion of formula I; ​ ​ ； ​ ​ or ， ​ ​ wherein ​ R2is -C(O)O - P1in formula I and V is -C(O)CF3and P1in formula VI is H.

4. The method of claim 2, wherein, ​ 5. The method of claim 4, wherein, ​ 6. The method of claim 2, wherein, ​ and, ​ 7. The method of claim 2, wherein, ​ 8. The method of claim 2, wherein, ​ 。 9. The method of claim 2, wherein, R2is -C(O)OH or -C(O)O - . ​ ​ ​ ； ​ ​ R 10 is -H, straight or branched chain alkyl, -C(O)alkyl, -C(O)O-alkyl, -C(O)NH-alkyl, -C(O)aryl, -C(O)O-aryl, -C(O)NH-aryl, -C(O)heteroaryl, -C(O)O-heteroaryl, and -C(O)N-heteroaryl; ​ ​ ； ​ ​ ​ ​ ​ 。 11. The method of claim 10, comprising oxidizing and preparing a compound of Formula VIII via the following intermediate: 。 12. The method of claim 10, comprising reducing, bicyclizing, and preparing a compound of Formula VIII via the following intermediate: 。 13. The method of claim 12, comprising further reducing and preparing a compound of Formula VIII via the following intermediate: 。 14. The method of claim 13, wherein, The compound of Formula XIII is reacted with 4-methoxyphenyl isocyanate, and the compound of Formula VIII is represented by the following structure: 。 15. A compound, or a pharmaceutically acceptable salt thereof, wherein, The compound is of Formula XV: ， wherein R1is ; wherein Z is selected from the group consisting of: wherein R2is C(O)R3; R3is -O - and the cation is associated with an ion of formula XVI, or R3is -OH; and, P1is selected from the group consisting of 9-fluorenylmethyl carbamate (Fmoc) and -C(O)CF3; wherein P1 is -C(O)CF3; wherein P1 is -C(O)CF3, 2-nitrobenzenesulfonyl, 4-nitrobenzenesulfonyl, or -H; wherein P1 is 2-nitrobenzenesulfonyl, 4-nitrobenzenesulfonyl, or -H; and wherein P1 is 2-nitrobenzenesulfonyl, 4-nitrobenzenesulfonyl, or -H; or a pharmaceutically acceptable salt thereof.

16. The compound or pharmaceutically acceptable salt of claim 15, wherein, The compound is a compound of Formula I: ； wherein R1is ; R2is C(O)R3; R3is -O - and a cation is associated with the ion of formula I, or R3is -OH; and, P1is -C(O)CF3; or a pharmaceutically acceptable salt thereof.

17. The compound or pharmaceutically acceptable salt of claim 15, wherein, The compound is a compound of Formula V: ； wherein R1is ; and P1is -C(O)CF3; or a pharmaceutically acceptable salt thereof.

18. The compound or pharmaceutically acceptable salt of claim 15, wherein, The compound is a compound of Formula VI: ； wherein R1is ; and P1is -C(O)CF3or -H; or a pharmaceutically acceptable salt thereof.

19. The compound or pharmaceutically acceptable salt of claim 15, wherein, The compound is a compound of Formula VII: ； wherein R1is ; and P1is a nitrogen protecting group selected from the group consisting of 2-nitrobenzenesulfonyl, 4-nitrobenzenesulfonyl or -H; or a pharmaceutically acceptable salt thereof.

20. The compound or pharmaceutically acceptable salt of claim 15, wherein, The compound is a compound of Formula VIIb: ； wherein R1is ; and P1is a nitrogen protecting group selected from the group consisting of 2-nitrobenzenesulfonyl, 4-nitrobenzenesulfonyl or -H; or a pharmaceutically acceptable salt thereof.

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