RU2481326C2 - Methods and intermediate compounds for producing steric compounds - Google Patents

Abstract

FIELD: chemistry.

SUBSTANCE: invention relates to methods of producing compounds of formula iii

and an optically enriched salt of the compound of formula iii, where R₁ is C₁-C₆ alkyl; R'₁ is hydrogen; R'₂ is -NHR₂; R₂ is C₃-C₆ cycloalkyl. The methods are realised by oxidising an unsaturated compound of formula i

, where the oxidant is tert-butylhydroperoxide, a mixture of samarium (III) isopropoxide, triphenyl arsine oxide, S-(-)1,1'-bi-2-naphthol and 4 Ǻ molecular sieves, or urea-hydrogen peroxide in the presence of trifluoroacetic anhydride to obtain a compound of formula ii

; and further reaction of the compound of formula ii with an amination agent, where the amination agent is an azide salt, and the intermediate azide-compound is reduced by hydrogenation to obtain a compound of formula iii. By reacting the compound of formula iii with an optically active organic acid selected from L-tartaric acid, malic acid, diisopropylidene gulonic acid and deoxycholic acid in a solvent, a salt of the compound of formula iii is obtained; and said salt is crystallised to obtain the same salt with more than 55% enantiomeric excess. The invention also relates to compounds: N-cyclopropyl-3-propyloxirane-2-carboxamide; 3-azido-N-cyclopropyl-2-hydroxyhexanamide; 3-amino-N-cyclopropyl-2-hydroxyhexanamide, salt of L-tartaric acid; 3-amino-N-cyclopropyl-2-hydroxyhexanamide, salt of deoxycholic acid.

EFFECT: improved methods of producing compounds of formula iii and an optically enriched salt of a compound of formula iii, novel intermediate compounds for producing serine protease inhibitors.

29 cl, 2 dwg, 14 ex

Description

This application establishes the priority of US application No. 60/782976, filed March 16, 2006, and US application No. 60/844771, filed September 15, 2006.

Field of Invention

The present invention relates to methods and intermediates for the preparation of protease inhibitors, in particular serine protease inhibitors.

BACKGROUND OF THE INVENTION

Hepatitis C virus infection ("HCV") is an urgent medical problem for humans. HCV is recognized as the agent that causes most cases of hepatitis other than hepatitis A and B, which has been determined to be present in serum in 3% of people worldwide [A. Alberti et al., "Natural History of Hepatitis C", J. Hepatology, 31., (Suppl. 1), p. 17-24 (1999)]. About four million people can be infected in the United States alone [M.J. Alter et al., "The Epidemiology of Viral Hepatitis in the United States, Gastroenterol. Clin. North Am., 23, p. 437-455 (1994); MJ Alter" Hepatitis C Virus Infection in the United States ", J. Hepatology, 31 (Suppl. 1), p. 88-91 (1999)].

Upon initial exposure to HCV, only about 20% of infected subjects develop acute clinical hepatitis, while others show a spontaneous resolution of the infection. However, in almost 70% of cases, the virus leads to a chronic infection that persists for decades [S. Iwarson, "The Natural Course of Chronic Hepatitis", FEMS Microbiology Reviews, 14, p. 201-204 (1994); D. Lavanchy, "Global Surveillance and Control of Hepatitis C", J. Viral Hepatitis, 6, p. 35-47 (1999)]. Long-term chronic infection usually leads to relapse and progressive complication of liver inflammation, which often leads to more serious diseases such as cirrhosis and hepatocellular carcinoma [M.C. Kew, "Hepatitis C and Hepatocellular Carcinoma", FEMS Microbiology Reviews, 14, p. 211-220 (1994); I. Saito et. al., "Hepatitis C Virus Infection is Associated with the Development of Hepatocellular Carcinoma", Proc. Natl. Acad. Sci. USA, 87, p. 6547-6549 (1990)]. Unfortunately, at the present time there are no broadly effective treatment methods to weaken the development of chronic HCV.

Compounds described as protease inhibitors and in particular serine protease inhibitors useful for treating HCV infections are disclosed in WO 02/18369. Also disclosed in this application are methods and intermediates for preparing such compounds. However, there remains a need for economical processes for the preparation of these compounds.

SUMMARY OF THE INVENTION

The present invention relates to methods and intermediates for producing alpha-amino beta-hydroxy acids of formula 1

where the variables R ₁ , R ' ₁ and R _{2 are} defined below and the compound of formula 1 has an enantiomeric excess (ee) of 55% or more.

The method includes the steps of oxidizing an unsaturated amide or ester to produce the corresponding epoxide, forming alpha hydroxy, beta amino acids using a suitable amination agent and separating the amine alcohol amide.

The methods and intermediates are specifically directed to the preparation of (2S, 3S) -3-amino-N-cyclopropyl-2-hydroxyhexanamide.

These methods and intermediates are useful for preparing a protease inhibitor of formula 2, wherein the variables R ₃ and R _{4 are} defined below.

In one aspect, the present invention discloses methods and intermediates used to prepare a serine protease inhibitor of formula 3.

DETAILED DESCRIPTION OF THE INVENTION

I. Definitions

), либо углеродного центра, с которым связана гидроксильная группа (также представлен звездочкой) в формуле 1, или обоих углеродных центров. Например, при нумерации от карбонильной группы соединения могут представлять собой (2S, 3S), (2S, 3R), (2R, 3R) или (2R, 3S) в этих двух углеродных центрах.As used herein, the term "enantiomeric excess (s) 55% or more" means that one enantiomer is 55% or more compared to another in a chemical. The enantiomer may be present as a result of either the carbon center to which the amino group (represented by an asterisk) is bound in formula 1 (

), or the carbon center to which the hydroxyl group is attached (also represented by an asterisk) in formula 1, or both carbon centers. For example, when numbering from a carbonyl group, the compounds may be (2S, 3S), (2S, 3R), (2R, 3R) or (2R, 3S) at these two carbon centers.

As used herein, “organic bases” that can be used in the method of the present invention include tertiary organic bases, which include, but are not limited to, trialkylamines, for example diethylisopropylamine, triethylamine, N-methylmorpholine, and the like, and heteroarylamines, for example pyridine, quinoline and the like.

As used herein, the term “aliphatic” embraces alkyl, alkenyl and alkynyl.

As used herein, an “alkyl” group refers to a saturated aliphatic hydrocarbon group containing 1-8 (eg, 1-6 or 1-4) carbon atoms. The alkyl group may be linear or branched. Examples of the alkyl group include, but are not limited to, methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, n-heptyl and 2-ethylhexyl. An alkyl group may optionally be substituted with one or more substituents, such as cycloalkyl, heterocycloalkyl, aryl, heteroaryl, alkoxy (two alkoxy groups on one atom or adjacent atoms can form a ring together with the atom (s) to which they are attached), aroyl, heteroaroyl , alkoxycarbonyl, alkylcarbonyloxy, acyl, sulfonyl (such as alkylsulfonyl or arylsulfonyl), sulfinyl (such as alkylsulfinyl), sulfanyl (such as alkylsulfanyl), sulfoxy, urea, thiourea, sulfamoyl, sulfamide, oxo, carb moyl, cycloalkyloxy, heterocycloalkyloxy, aryloxy, heteroaryloxy, aralkyloxy, heteroarylalkoxy, amino, nitro, carboxy, cyano, oxo, halogen, hydroxy, sulfo, mercapto, alkylsulfanyl, alkylsulfonylalkylcarbonylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylcarbonyl aralkylcarbonylamino, heterocycloalkyl-carbonylamino, heterocycloalkyl-alkylcarbonylamino, heteroarylcarbonylamino or heteroalkylcarbonylamino.

As used herein, an “alkenyl" group refers to an aliphatic carbon group that contains 2-8 (e.g., 2-6 or 2-4) carbon atoms and at least one double bond. Like an alkyl group, an alkenyl group may be linear or branched. Examples of the alkenyl group include, but are not limited to, allyl, isoprenyl, 2-butenyl and 2-hexenyl. An alkenyl group may optionally be substituted with one or more substituents, such as cycloalkyl, heterocycloalkyl, aryl, heteroaryl, alkoxy (two alkoxy groups on one atom or adjacent atoms can form a ring together with the atom (s) to which they are attached), aroyl, heteroaroyl , alkoxycarbonyl, alkylcarbonyloxy, acyl, sulfonyl (such as alkylsulfonyl or arylsulfonyl), sulfinyl (such as alkylsulfinyl), sulfanyl (such as alkylsulfanyl), sulfoxy, urea, thiourea, sulfamoyl, sulfamide, oxo, ca bamoyl, cycloalkyloxy, heterocycloalkyloxy, aryloxy, heteroaryloxy, aralkyloxy, heteroarylalkoxy, amino, nitro, carboxy, cyano, oxo, halogen, hydroxy, sulfo, mercapto, alkylsulfanyl, alkylsulfonyl, alkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkylalkyl heterocycloalkyl-carbonylamino, heterocycloalkyl-alkylcarbonylamino, heteroarylcarbonylamino or heteroaralkylcarbonylamino.

As used herein, an “alkynyl" group refers to an aliphatic carbon group that contains 2-8 (eg, 2-6 or 2-4) carbon atoms and contains at least one triple bond. The alkynyl group may be linear or branched. Examples of the alkynyl group include, but are not limited to, propargyl and butynyl. An alkynyl group may optionally be substituted with one or more substituents, such as cycloalkyl, heterocycloalkyl, aryl, heteroaryl, alkoxy (two alkoxy groups on one atom or adjacent atoms can form a ring together with the atom (s) to which they are attached), aroyl, heteroaroyl , alkoxycarbonyl, alkylcarbonyloxy, acyl, sulfonyl (such as alkylsulfonyl or arylsulfonyl), sulfinyl (such as alkylsulfinyl), sulfanyl (such as alkylsulfanyl), sulfoxy, urea, thiourea, sulfamoyl, sulfamide, oxo, ca BAMO, cycloalkyloxy, geterotsikloalkiloksi, aryloxy, heteroaryloxy, aralkyloxy, heteroarylalkoxy, amino, nitro, carboxy, cyano, oxo, halogen, hydroxy, sulfo, mercapto, alkylsulfanyl, alkylsulfinyl, alkylsulfonyl, aminocarbonyl, alkylcarbonylamino, cycloalkylcarbonylamino, cycloalkyl-alkylcarbonylamino, arylcarbonylamino, aralkylcarbonylamino, heterocycloalkyl-carbonylamino, heterocycloalkyl-alkylcarbonylamino, heteroarylcarbonylamino or heteroalkylcarbonylamino.

As used herein, an “amino” group refers to —NR _x R _y , where each of R _x and R _y independently is hydrogen, alkyl, cycloalkyl, (cycloalkyl) alkyl, aryl, aralkyl, heterocycloalkyl, (heterocycloalkyl) alkyl, heteroaryl or heteroalkyl, each of which is defined herein and is optionally substituted. When the term “amino” does not mean a terminal group (for example, alkylcarbonylamino), it is represented by the formula —NR _x -. R _x has the meanings given above.

As used herein, an “aryl” group, used alone or as part of a larger group, as in “aralkyl,” “aralkoxy,” or “aryloxyalkyl,” refers to a phenyl, naphthyl, or benzocondensed group containing 2 to 3 rings. For example, a benzofused group includes phenyl fused to one or two C _4-8 carbocyclic groups, for example, 1,2,3,4-tetrahydronaphthyl, indanyl or fluorenyl. Aryl is optionally substituted with one or more substituents, such as alkyl (including carboxyalkyl, hydroxyalkyl and haloalkyl such as trifluoromethyl), alkenyl, alkynyl, cycloalkyl, (cycloalkyl) alkyl, heterocycloalkyl, (heterocycloalkyl) alkyl, aryl, heteroaryloalkoxy, alkoxy , heterocycloalkyloxy, aryloxy, heteroaryloxy, aralkyloxy, heteroaralkyloxy, aroyl, heteroaroyl, amino, nitro, carboxy, alkoxycarbonyl, alkylcarbonyloxy, aminocarbonyl, alkylcarbonylamino, cycloalkylcarbonylamino, (cycloalkyl) kylcarbonylamino, arylcarbonylamino, aralkylcarbonylamino, (heterocycloalkyl) carbonylamino, (heterocycloalkyl) alkylcarbonylamino, heteroarylcarbonylamino, heteroaralkylcarbonylamino, cyano, halogen, hydroxy, acycloalkyl, , sulfoxy, urea, thiourea, sulfamoyl, sulfamide, oxo or carbamoyl.

As used herein, an “aralkyl” group refers to an alkyl group (eg, a C _1-4 alkyl group) that is substituted with an aryl group. Both “alkyl” and “aryl” are defined above. An example of an aralkyl group is benzyl. “Heteroaralkyl” group refers to an alkyl group which is substituted with heteroaryl. Both “alkyl” and “heteroaryl” are defined herein. As used herein, a “cycloaliphatic” group encompasses a “cycloalkyl” group and a “cycloalkenyl” group.

As used herein, a “cycloalkyl” group refers to a saturated carbocyclic mono- or bicyclic (fused or bridged) ring of 3-10 (eg, 5-10) carbon atoms. Examples of cycloalkyl groups include cyclopropyl, cyclopentyl, cyclohexyl, cycloheptyl, adamantyl, norbornyl, cubyl, octahydroindenyl, decahydronaphthyl, bicyclo [3.2.1] octyl, bicyclo [2.2.2] octyl, bicyclo [3.3.1] nonyl and bicyclo [3.3. 2] decyl and adamantyl. A "cycloalkenyl" group, as used herein, refers to a non-aromatic carbocyclic ring of 3-10 (e.g., 4-8) carbon atoms containing one or more double bonds. Examples of cycloalkenyl groups include cyclopentenyl, 1,4-cyclohexadienyl, cycloheptenyl, cyclooctenyl, hexahydroindenyl, octahydronaphthyl, bicyclo [2.2.2] octenyl and bicyclo [3.3.1] nonenyl. The cycloalkyl or cycloalkenyl group may optionally be substituted with one or more substituents, such as alkyl (including carboxyalkyl, hydroxyalkyl and haloalkyl, such as trifluoromethyl), alkenyl, alkynyl, cycloalkyl, (cycloalkyl) alkyl, heterocycloalkyl, (heterocycloalkyl, alkyl) , alkoxy, cycloalkyloxy, heterocycloalkyloxy, aryloxy, heteroaryloxy, aralkyloxy, heteroaralkyloxy, aroyl, heteroaroyl, amino, nitro, carboxy, alkoxycarbonyl, alkylcarbonyloxy, aminocarbonyl, alkylcarbonylamino, ikloalkilkarbonilamino, (cycloalkyl) alkylcarbonylamino, arylcarbonylamino, aralkylcarbonylamino, (heterocycloalkyl) carbonylamino, (heterocycloalkyl) alkylcarbonylamino, geteroarilkarbonilamino, geteroaralkilkarbonilamino, cyano, halo, hydroxy, acyl, mercapto, sulfonyl (such as alkylsulfonyl or arylsulfonyl), sulfinyl (such as alkylsulfinyl) sulfonyl (such as alkylsulfanyl), sulfoxy, urea, thiourea, sulfamoyl, sulfamide, oxo or carbamoyl.

As used herein, the term “heterocycloaliphatic” embraces a heterocycloalkyl group and a heterocycloalkenyl group.

As used herein, a “heterocycloalkyl” group refers to a 3-10 membered mono- or bicyclic (fused or linked bridging) (eg, 5-10 membered mono- or bicyclic) saturated ring structure in which one or several ring atoms are a heteroatom, for example N, O or S. Examples of a heterocycloalkyl group include piperidinyl, piperazinyl, tetrahydropyranyl, tetrahydrofuryl, dioxolanyl, oxazolidinyl, isoxazolidinyl, morpholinyl, octahydrobenzofuryl, octahyd ohromenyl, octahydrothiochromenyl, octahydroindolyl, octahydropyrindinyl, decahydroquinolinyl, octahydrobenzo [b] thiophenyl, 2-oxabicyclo [2.2.2] octyl, 1-azabicyclo [2.2.2] octyl, 3-azabicyclo [2,2.1] dioxatricyclo [3.3.1.03,7] nonyl. A monocyclic heterocycloalkyl group may be fused to a phenyl group such as tetrahydroisoquinoline. A “heterocycloalkenyl” group, as used herein, refers to a mono- or bicyclic (eg, 5-10 membered mono- or bicyclic) non-aromatic ring structure containing one or more double bonds and in which one or more ring atoms represent a heteroatom, for example N, O or S. A heterocycloalkyl or heterocycloalkenyl group may optionally be substituted with one or more substituents, such as alkyl (including carboxyalkyl, hydroxyalkyl and haloalkyl, such such as trifluoromethyl), alkenyl, alkynyl, cycloalkyl, (cycloalkyl) alkyl, heterocycloalkyl (such as benzimidazolidinyl), (heterocycloalkyl) alkyl, aryl, heteroaryl, alkoxy (two alkoxy groups on the same atom or on adjacent atoms can form a ring to the atom (s) to which they are attached), cycloalkyloxy, heterocycloalkyloxy, aryloxy, heteroaryloxy, aralkyloxy, heteroaralkyloxy, aroyl, heteroaroyl, amino, nitro, carboxy, alkoxycarbonyl, alkylcarbonyloxy, aminocarbonyl, alkylcarbonylalkyl , (cycloalkyl) alkylcarbonylamino, arylcarbonylamino, aralkylcarbonylamino, (heterocycloalkyl) carbonylamino, (heterocycloalkyl) alkylcarbonylamino, heteroarylcarbonylamino, heteroaralkylcarbonylalkyl, sulfonyl, hydroxyalkyl, acylalkyl, acylalkyl, acylalkyl, acylalkyl, acylalkyl, acylalkyl, acylalkyl, acylalkyl, acylalkyl, acylalkyl, acylalkyl, acylalkyl, acylalkyl, acylalkyl, acylalkyl, acylalkyl, acylalkyl, acylalkyl, acylalkyl, acylalkyl, aryl, aryl, aryl, aryl, aryl, aryl, aryloxy sulfanyl (such as alkylsulfanyl), sulfoxy, urea, thiourea, sulfamoyl, sulfamide, oxo or carbamoyl.

A “heteroaryl” group, as used herein, refers to a monocyclic, bicyclic or tricyclic ring structure containing 4-15 ring atoms, where one or more ring atoms are a heteroatom, for example N, O or S, and where one or several rings in a bicyclic or tricyclic ring structure are aromatic. The heteroaryl group includes a benzofused ring system containing 2-3 rings. For example, a benzofused group includes phenyl fused to one or two C _4-8 heterocyclic groups, for example indolinyl and tetrahydroquinolinyl. Some examples of heteroaryl include azetidinyl, pyridyl, furyl, pyrrolyl, thienyl, thiazolyl, oxazolyl, imidazolyl, indolyl, tetrazolyl, benzofuryl, isoquinolinyl, benzthiazolyl, xanthene, thioxanthene, phenothiazine, dihydroindole diol [1,3]. Heteroaryl is optionally substituted with one or more substituents, such as alkyl (including carboxyalkyl, hydroxyalkyl and haloalkyl such as trifluoromethyl), alkenyl, alkynyl, cycloalkyl, (cycloalkyl) alkyl, heterocycloalkyl, (heterocycloalkyl) alkyl, aryl, heteroaryloalkyl, alk heterocycloalkyloxy, aryloxy, heteroaryloxy, aralkyloxy, heteroaralkyloxy, aroyl, heteroaroyl, amino, nitro, carboxy, alkoxycarbonyl, alkylcarbonyloxy, aminocarbonyl, alkylcarbonylamino, cycloalkylcarbonylamino, (cycloalkyl) rbonylamino, arylcarbonylamino, aralkylcarbonylamino, (heterocycloalkyl) carbonylamino, (heterocycloalkyl) alkylcarbonylamino, heteroarylcarbonylamino, heteroaralkylcarbonylamino, cyano, halogen, hydroxy, acyl, alkyl sulfonyl, alkylsulfanyl), sulfoxy, urea, thiourea, sulfamoyl, sulfamide, oxo or carbamoyl. A “heteroaralkyl” group, as used herein, refers to an alkyl group (eg, a C _1-4 alkyl group) that is substituted with a heteroaryl group. Both “alkyl” and “heteroaryl” are defined above.

As used herein, a “cyclic group” includes cycloalkyl, heterocycloalkyl, cycloalkenyl, heterocycloalkenyl, aryl or heteroaryl, each of which is defined above.

As used herein, an “acyl" group refers to a formyl group or an alkyl-C (= O) - group, where "alkyl" is defined above. Acetyl and pivaloyl are examples of acyl groups.

As used herein, a “carbamoyl” group refers to a group having the structure —O — CO — NR _x R _y or —NR _x —CO — OR _z , where R _x and R _{y are as} defined above and R _z may represent alkyl, aryl, aralkyl, heterocycloalkyl, heteroaryl or heteroaralkyl.

As used herein, the “carboxy” and “sulfo” group refer to —COOH or —COOR _x and —SO ₃ H or —SO ₃ R _x, respectively.

As used herein, an “alkoxy” group refers to an alkyl-O— group, where “alkyl” is defined above.

As used herein, a “sulfoxy” group refers to —Q — SO — R _x or —SO — OR _x , where R _{x is as} defined above.

As used herein, a “sulfonyl” group refers to —S (O) ₂ —R _x , where R _{x is as} defined above.

As used herein, a “sulfinyl” group refers to —S (O) —R _x , where R _{x is as} defined above.

As used herein, a “sulfanyl” group refers to —SR _x , where R _{x is as} defined above.

As used herein, the group “halogen” or “halo” refers to fluoro, chloro, bromo or iodo.

As used herein, a “halogen-aliphatic" group refers to an aliphatic group substituted with 1-3 halogen atoms. For example, the term haloalkyl includes the group —CF ₃ .

As used herein, a “sulfamoyl” group refers to the structure —S (O) ₂ —NR _x R _y or —NR _x —S (O) ₂ —R _z , where R _x , R _y, and R _{z are as} defined above .

As used herein, a “sulfamide” group refers to the structure —NR _x —S (O) ₂ —NR _y R _z , where R _x , R _y, and R _{z are as} defined above.

As used herein, a “carbonylamino” group, used alone or in combination with another group, refers to an amido group such as —C (O) —NR _x -, —NR _x —C (O) -, and —C ( O) -N (R _x ) ₂ . For example, alkylcarbonylamino includes alkyl-C (O) -NR _x - and alkyl-NR _x -C (O) -.

As used herein, the urea group refers to the —NR _x —CO — NR _y R _z structure, and the thiourea group refers to the —NR _x —CS-NR _y R _z structure. R _x , R _y and R _{z are as} defined above.

The phrase "optionally substituted" is used interchangeably with the phrase "substituted or unsubstituted." As described herein, the compounds of the present invention may optionally be substituted with one or more substituents, such as those generically illustrated above or exemplified by specific classes, subclasses, and species of the present invention. As described herein, variables encompass specific groups, such as alkyl and aryl. Unless otherwise indicated, each of the specific groups for the variables may optionally be substituted with one or more substituents described in this application. Each substituent of a particular group is optionally further substituted with one to three substituents selected from halogen, cyano, alkoxy, hydroxyl, nitro, haloalkyl and alkyl. For example, an alkyl group may be substituted with alkylsulfanyl, and alkylsulfanyl may optionally be substituted with one to three substituents selected from halogen, cyano, alkoxy, hydroxyl, nitro, haloalkyl and alkyl. As a further example, the cycloalkyl part of the (cycloalkyl) carbonylamino may optionally be substituted with one to three substituents selected from halogen, cyano, alkoxy, hydroxyl, nitro, haloalkyl and alkyl.

Typically, the term “substituted” whether or not the term “optionally” is present before it, refers to the substitution of hydrogen radicals in a given structure by a radical of the indicated substituent. Specific substituents are described above in the definitions and below in the description of the compounds and their examples. Unless otherwise specified, an optionally substituted group may contain a substituent at each position of the group that may be substituted, and when in any particular structure more than one position may be substituted by more than one substituent selected from the specified group, such substituents may either the same or different from each other in each position. A ring substituent, such as heterocycloalkyl, may be bonded to another ring, such as cycloalkyl, to form a spiro-bicyclic ring system, for example, both rings contain one atom common to these rings. As should be understood by those skilled in the art, combinations of substituents contemplated by the present invention are those combinations that provide stable or chemically achievable compounds.

The phrase “stable or chemically achievable”, as used herein, refers to compounds that are not substantially altered, subject to conditions that make it possible to obtain, determine and preferably isolate, purify and use one or more of them appointments that are disclosed in this application. In some embodiments, the stable compound or chemically achievable compound is a compound that is substantially unchanged when it is held at a temperature of 40 ° C or lower, in the absence of moisture or in other chemically reactive conditions, for at least a week .

As used herein, the term “bicyclic fused ring system” or “bicyclic ring system” refers to two rings in which two atoms are common to these rings. Any ring may be saturated, partially unsaturated or aromatic. Each ring may also contain 1-3 heteroatoms.

As used herein, the term “tricyclic fused ring system” or “tricyclic ring system” refers to a bicyclic ring system in which the third ring is fused to the bicyclic ring system such that the third ring has at least two common atom with a bicyclic ring system. In some embodiments, all three rings have at least one common atom. Any of the rings in the tricyclic ring system may be saturated, partially unsaturated, or aromatic. Each of the rings may include 1-3 heteroatoms.

In some embodiments, aliphatic groups, alkyl groups, aryl groups, heterocyclic groups, carbocyclic groups, and bicyclic or tricyclic ring systems contain one or more substituents. The substituents are selected from those that are stable under the reaction conditions of the method of the present invention, as should be known to specialists in this field. Examples of substituents include halogen, —Q ₁ , —OQ ₁ , —OH, protected OH (such as acyloxy), phenyl (Ph), substituted Ph, —OPh, substituted —OPh, —NO ₂ , —CN, —NHQ ₁ , -N (Q ₁ ) ₂ , -NHCOQ ₁ , -NHCONHQ ₁ , -NQ ₁ CONHQ ₁ , -NHCON (Q ₁ ) ₂ , -NQ ₁ CON (Q ₁ ) ₂ , -NQ ₁ COQ ₁ , -NHCO ₂ Q ₁ , -NQ ₁ CO ₂ Q ₁ , -CO ₂ Q ₁ , -COQ ₁ , -CONHQ ₁ , -CON (Q ₁ ) ₂ , -S (O) ₂ Q ₁ , -SONH ₂ , -S (O) Q ₁ , -SO ₂ NHQ ₁ , -SO ₂ N (Q ₁ ) ₂ , -NHS (O) ₂ Q ₁ , -NQ ₁ S (O) ₂ Q ₁ , = O, = S, = NNHQ ₁ , = NN (Q ₁ ) ₂ , = N-OQ ₁ , = NNHCOQ ₁ , = NNQ ₁ СOQ ₁ , = NNНСО ₂ Q ₁ , = NNQ ₁ СО ₂ Q ₁ , = NNНSO ₂ Q ₁ , = NNQ ₁ SO ₂ Q ₁ or = NQ ₁ , where Q ₁ is an optionally substituted aliphatic group, an aryl or aralkyl group.

As used herein, nitrogen atoms in a heterocyclic ring may optionally be substituted. Suitable nitrogen substituents include Q ₂ , COQ ₂ , S (O) ₂ Q ₂ and CO ₂ Q ₂ , where Q ₂ represents an aliphatic group or a substituted aliphatic group.

Unless otherwise indicated, the structures presented in this application also include all stereochemical forms of these structures; those. R- and S-configurations for each asymmetric center. Therefore, individual stereochemical isomers as well as enantiomeric and diastereomeric mixtures of the compounds of the present invention are included in the scope of the present invention.

The term “substantially pure” refers to the stereochemical purity of a compound that is greater than 90%. In some embodiments, the stereochemical purity of the compound is greater than 95%. In other embodiments, the stereochemical purity of the compound is 99% or more.

The term "selective crystallization" means the crystallization of a substantially pure isomer from a solvent containing a mixture of isomers.

The term "dynamic crystallization" means the crystallization of a substantially pure isomer from a solvent containing a mixture of isomers, under conditions that cause isomerization of the mixture of isomers to produce an isomer that selectively crystallizes. For example, in the case of separation of enantiomers, the isomerization of the more soluble enantiomer to a less soluble isomer results in crystallization of the less soluble isomer, since the equilibrium between the isomers is regulated by crystallization towards the less soluble enantiomer. A specific example of dynamic crystallization may include the epimerization of anomeric carbon in a solvent under conditions in which selective crystallization of one substantially pure enantiomer occurs.

Unless otherwise indicated, the structures provided herein also include compounds that differ only in the presence of one or more isotopically enriched atoms.

Various "protecting groups", "blocking groups" or "amine blocking groups" can be used in the methods of the present invention. Examples of amine blocking groups or protecting groups include, but are not limited to, —Q ⁷ , —C (O) Q ⁷ , —C (O) OQ ⁷ , —SOQ ⁷ , —SO ₂ Q ⁷ , —SO ₃ Q ⁷ , -SO ₂ N (Q ⁷ ) ₂ , -C (O) C (O) Q ⁷ , -C (O) C (O) OQ ⁷ , -C (O) CH ₂ C (O) Q ⁷ , - C (O) N (Q ⁷ ) ₂ , - (CH ₂ ) _0-2 NHC (O) Q ⁷ , -C (= NH) N (Q ⁷ ) ₂ , -C (O) N (OQ ⁷ ) Q ⁷ , -C (= NOQ ⁷ ) Q ⁷ , -P (O) (Q ⁷ ) ₂ and -P (O) (OQ ⁷ ) ₂ ; where Q ⁷ represents hydrogen, an optionally substituted aliphatic group, an optionally substituted aryl group, or an optionally substituted heterocyclic group. Preferably, Q ⁷ represents a C _1-12 aliphatic group, a C _3-10 cycloaliphatic group, (a C _3-10 cycloaliphatic group) a C _1-12 aliphatic group, a C _6-10 aryl, (C _6-10 aryl) - (C _1-12 aliphatic group) -, C _3-10 heterocyclyl, (C _6-10 heterocyclyl) -C _1-12 aliphatic group, C _5-10 heteroaryl or (C _5-10 heteroaryl) - (C _1-12 aliphatic group) -.

As used herein, the term “Lewis acid” refers to a group capable of socializing or accepting an electron pair. Examples of Lewis acids include, but are not limited to, BF ₃ etherates and metal halides, alkoxides and mixed halides / alkoxides (e.g., Al (O-alkyl) ₂ Cl, Al (O-alkyl) Cl ₂ ). Metals can be aluminum, titanium, zirconium, magnesium, copper, zinc, iron, tin, boron, yttrium, lanthanum and samarium.

EDCI is 1- (3-dimethylaminopropyl) -3-ethylcarbodiimide. HOBt is 1-hydroxybenzotriazole. HOSuc is N-hydroxysuccinimide. THF is tetrahydrofuran. TFA is trifluoroacetic acid. DCM is dichloromethane. DMAP is 4-dimethylaminopyridine. DIPEA is diisopropylethylamine. DMF (DMF) is dimethylformamide. TFA is trifluoroacetic acid. CBZ is benzyloxycarbonyl. ¹ H-NMR is proton nuclear magnetic resonance. TLC is thin layer chromatography. TEMPO is a 2,2,6,6-tetramethylpiperidinyloxy free radical.

II. Methods and intermediates

Basically, the present invention relates to methods and intermediates used to produce spatially specific compounds.

Specifically, the methods and intermediates described herein are useful for preparing an HCV protease inhibitor of formula 2.

Where

R ₃ represents RW- or P4-L3-P3-L2-P2-;

R ₄ represents —NH — CR ₁ R ′ ₁ —CH (OH) C (O) —NHR ₂ ;

each W independently represents a bond, —NR ₄ , —O— or —S—;

each of P2, P3 and P4 independently represents a bond, H, an optionally substituted aliphatic group, an optionally substituted heteroaliphatic group, an optionally substituted aryl, an optionally substituted heteroaryl, an optionally substituted alkoxy, an optionally substituted alkylsulfanyl, an optionally substituted aralkoxy, an optionally substituted aralkylsulfanyl, mono- or dialkylamino, optionally substituted mono- or diarylamino, or optionally substituted mono- or diheteroarylamino, provided that

when L2 is absent and P3 is H, then L3 and P4 are absent;

when P2 is not an end group, then P2 is connected to the core structure of formula 3 and P2 is also linked to L2 if this group is present, or to P3 if L2 is absent;

when P3 is not an end group, then P3 is connected to L2 if this group is present, or to P2 if L2 is absent, and P3 is also connected to L3 if this group is present, or to P4 if L3 is absent;

each L2 or L3 independently represents a bond, —C (O) - or —SO ₂ -;

each R ₁ and R ′ ₁ independently represents H, an optionally substituted aliphatic group, an optionally substituted aryl, an optionally substituted aralkyl, an optionally substituted heteroaliphatic group or an optionally substituted heteroalkyl, or each R ₁ and R ′ ₁ together with the atom to which they are attached may form a 3-7 membered optionally substituted cycloaliphatic ring.

In some embodiments, R ₃ is P2-, which is represented by the structure:

Where

each T independently represents a bond, H, —C (O) -, —OC (O) -, —NHC (O) -, —C (O) C (O) -, or —SO ₂ -;

each R independently represents H, an optionally substituted aliphatic group, an optionally substituted heteroaliphatic group, an optionally substituted cycloaliphatic group, an optionally substituted heterocyclic group, an optionally substituted aralkyl group, an optionally substituted heteroaralkyl group, an optionally substituted aryl group or an optionally substituted heteroaryl; and

each R ₅ and R ₆ independently represents H, an optionally substituted aliphatic group, an optionally substituted heteroaliphatic group, an optionally substituted heteroaryl, an optionally substituted phenyl, an optionally substituted aralkyl or an optionally substituted heteroarylalkyl, or

R ₅ and its adjacent R ₆ , taken together with the atoms to which they are attached, form a 5-7 membered, optionally substituted monocyclic heterocycle or a 6-12 membered, optionally substituted bicyclic heterocycle in which each heterocyclic ring optionally contains an additional a heteroatom selected from —O—, —S— or —NR ₄ -; and each R ₇ independently represents H, an optionally substituted aliphatic group, an optionally substituted heteroaliphatic group, an optionally substituted heteroaryl, or an optionally substituted phenyl.

In some embodiments, R ₁ is P3-L2-P2, which is represented by the structure:

In some embodiments, R ₃ is P4-L3-P3-L2-P2, which is represented by the structure:

Where

each T independently represents a bond, H, —C (O) -, —OC (O) -, —NHC (O) -, —C (O) C (O) -, or —SO ₂ -;

each R independently represents H, an optionally substituted aliphatic group, an optionally substituted heteroaliphatic group, an optionally substituted cycloaliphatic group, an optionally substituted heterocyclic group, an optionally substituted aralkyl group, an optionally substituted heteroaralkyl group, an optionally substituted aryl group or an optionally substituted heteroaryl;

each R ₅ , R ₆ , R ₇ and R ₈ independently represents H, an optionally substituted aliphatic group, an optionally substituted heteroaliphatic group, an optionally substituted heteroaryl, an optionally substituted phenyl, an optionally substituted aralkyl or an optionally substituted heteroarylalkyl, or

R ₅ and its adjacent R ₆ , taken together with the atoms to which they are attached, form a 5-7 membered, optionally substituted monocyclic heterocycle or a 6-12 membered, optionally substituted bicyclic heterocycle in which each heterocyclic ring optionally contains an additional a heteroatom selected from —O—, —S— or —NR ₄ -; and each R ₇ independently represents H, an optionally substituted aliphatic group, an optionally substituted heteroaliphatic group, an optionally substituted heteroaryl, or an optionally substituted phenyl;

R ₇ and adjacent R ₆ , taken together with the atoms to which they are bonded, can form a 5-7 membered, optionally substituted monocyclic heterocycle, 5-7 membered, optionally substituted monocyclic aryl, 6-12 membered, optionally a substituted bicyclic heterocycle or a 6-12 membered optionally substituted bicyclic aryl, where each heterocyclic or aryl ring optionally contains an additional heteroatom selected from —O—, —S— or —NR ₄ -;

R ₈ and its adjacent R ₆ , taken together with the atoms to which they are bonded, form a 5-7 membered, optionally substituted monocyclic heterocycle, 5-7 membered, optionally substituted monocyclic heteroaryl, 6-12 membered optionally substituted a bicyclic heterocycle or a 6-12 membered optionally substituted bicyclic heteroaryl, where each heterocyclic or heteroaryl ring optionally contains an additional heteroatom selected from —O—, —S— or —NR ₄ -;

R ₈ and R taken together with the atoms to which they are bonded form a 5-7 membered, optionally substituted monocyclic heterocycle, 5-7 membered, optionally substituted monocyclic aryl, 6-12 membered, optionally substituted bicyclic heterocycle or 6 A 12-membered optionally substituted bicyclic aryl, where each heterocyclic or aryl ring optionally contains an additional heteroatom selected from —O—, —S— or —NR ₄ -;

when R ₅ and R ₆ together with the atoms to which they are bonded form a ring, R ₇ and the ring system formed by R ₅ and R ₆ can form an 8-14 membered, optionally substituted bicyclic fused ring system, where such a bicyclic fused the ring system is also optionally fused to optionally substituted phenyl to give an optionally substituted 10-16 membered tricyclic fused ring system.

An example of an HCV protease inhibitor of formula 2 is a compound of formula 3 below.

In one aspect, the present invention provides methods and intermediates for the preparation of an α-hydroxy-β-amino acid derivative of formula 1, which is useful for preparing protease inhibitors:

where R ₁ and R ′ ₁ each independently represents H, an optionally substituted aliphatic group, an optionally substituted cycloaliphatic group, an optionally substituted arylaliphatic group, an optionally substituted heteroaliphatic group, or an optionally substituted heteroarylaliphatic group, and R ₂ represents H, an optionally substituted aliphatic a group, an optionally substituted cycloaliphatic group, an optionally substituted arylaliphatic group, an optionally substituted heteroaliphate a chemical group or an optionally substituted heteroaryl aliphatic group, and the amino alcohol amide of formula 1 has an enantiomeric excess (ee) of greater than 55% (for the definition of ee, see, for example, Jerry March, Advanced Organic Chemistry, John Wiley and Sons, Inc., 1992, p. 125).

In one embodiment, the present invention provides a method and intermediates for preparing a compound of formula 1, as shown generally in Scheme 1.

According to the scheme, IR ₁ and R ′ ₁ have the meanings indicated above; R ′ ₂ is —NHR ₂ or —OE, where R ₂ is as defined above and E is C ₁ -C ₅ alkyl or optionally substituted benzyl. Unsaturated compound i is converted to epoxide ii (step a) using known methods, for example, oxidation with peracid, such as, for example, meta-chloroperbenzoic acid or peracetic acid (see, for example, RS Porto, MLAA Vasconcellos, E. Ventura, F. Coelho, Synthesis, 2005, 2297-2306), hydrogen peroxide (see, e.g., Dorothee Felix, Claude Wintner and A. Eschenmoser, Organic Synthesis, Collective Volume 6, p. 679), urea-hydrogen peroxide (also called urea hydroperoxide ) in the presence of trifluoroacetic anhydride, Oxone® (KHSO ₅ peroksomonosulfat potassium) or an organic peroxide, so m, such as tert-butyl hydroperoxide. Alternatively, epoxide ii can be prepared by condensation using a glycidyl ester (see, e.g., M. Ballester, Chem. Revs. 55, 283-300 (1955); DM Burness, Organic Synthesis, Collective Volume 4, p. 649) .

In some embodiments, epoxidation can be carried out to obtain optically enriched epoxides (see, for example, H. Kakei, R. Tsuji, T. Ohshima, M. Shibasaki, J. Am. Chem. Soc, 2005, 127, 8962-8963). ; M. Marigo, J. Franzen, TB Poulsen, W. Zhuang, KA Jorgensen, J. Am. Chem. Soc, 2005, 127, 6284-6289; M.Shibisaki et.al., US Pat. No. 6,833,442 (BINOL Ars complex); R. Kino, K. Daikai, T. Kawanami, H. Furuno, J. Inanaga, Org. Biomol. Chem., 2004, 2, 1822-1824; Y. Shi, US Pat. No. 6,348,608 (OXONE , EDTA, optically active ketone)).

The epoxidation step can be carried out using either an ester (R ′ ₂ = —OE) or an amide (R ′ ₂ = —NHR ₂ ). When the epoxidation step is carried out using an ester, this ester is then converted to an amide. The present invention provides that amide formation can be carried out at any stage of the process using known methods and protecting groups, where appropriate.

Reaction of the epoxide ii with a suitable amination agent (step b) gives amino alcohol 3. Suitable amination agents are those which can be converted to the amino compound iii. Examples of suitable amination agents include azide, phthalimide and optionally substituted benzylamine.

In step c, the mixture of amino alcohols of formula iii is separated to give an optically active compound of formula iv. Suitable methods for separating mixture iii include, for example, salt formation with a suitable optically active organic acid.

Suitable optically active organic acids include, but are not limited to, tartaric acid, malic acid, diisopropylidengulonic acid, and deoxycholic acid.

In one embodiment, R ′ _{2 of} formula i is —NHR ₂ .

In one embodiment, the epoxidation of compound i is carried out using tert-butyl hydroperoxide in the presence of a base, such as, for example, sodium hydroxide or butyl lithium.

In another embodiment, epoxidation is carried out using potassium monopersulfate, ethylenediaminetetraacetic acid, and optionally optically active ketone.

In one embodiment, the amino alcohol of formula iii has a trans configuration.

In one embodiment, the compound of formula iv has a 2- (S) -, 3 (S) configuration.

In one embodiment, the amination of compound ii to produce amino alcohol iii is carried out by reacting compound ii with sodium azide followed by reduction of the intermediate azide compound with hydrogen in the presence of a palladium-carbon catalyst.

In another embodiment, separation iii to iv is accomplished by forming a salt with an optically active acid and crystallizing the salt thus obtained.

In another embodiment, the optically active organic acid is tartaric acid.

In a further embodiment, the optically active organic acid is deoxycholic acid.

In one embodiment, R ₁ is C ₁ -C ₆ alkyl and R ′ ₁ is H.

In another embodiment, R ₂ is C ₁ -C ₆ alkyl or C ₁ -C ₆ cycloalkyl.

In another embodiment, R ₂ is cyclopropyl.

In another embodiment, the aminohydroxy compounds of formula iii can be prepared according to the methods described in US Pat. Nos. 6,020,518, 6,087,530 and 6639094, each of which is incorporated herein by reference in its entirety.

In another embodiment, as shown in Scheme II, the present invention provides a method and intermediates for preparing a compound of formula 3.

In Scheme II, a bicyclic amino ester of formula 1a is reacted with a protected amino acid of formula 5, wherein Z is an amino-protecting group that can be removed under acidic, basic or hydrogenation conditions other than those used to remove the R ₁ protecting group, in the presence of a coupling agent to give an amido ester of formula 6. The protecting group Z is removed from the amido ester compound of formula 6 to give an amino ester compound of formula 7.

The interaction of the amino compounds of formula 7 with a protected amino acid 8 in the presence of a coupling agent gives a tripeptide of the formula 9.

Removal of the protective group Z in the tripeptide of formula 9 provides a free amino-tripeptide of formula 10.

The reaction of an amino tripeptide of formula 10 with pyrazine-2-carboxylic acid in the presence of a coupling agent gives an amide tripeptide ester of formula 11.

Hydrolysis of an amide tripeptide ester of formula 11 provides an amide tripeptide acid of formula 12.

The reaction of an amide-tripeptide acid of formula 12 with an amino-hydroxyamide of formula 20 in the presence of a coupling agent gives a hydroxy peptide of formula 13.

In the final step, oxidation of the hydroxy group of formula 12 provides a compound of formula 3.

Any of the intermediates prepared as described herein can be used with or without isolation from the reaction mixture. The desired protease inhibitor can be obtained by attaching a suitable P ₂ , P ₂ -P ₃ or P ₂ -P ₃ -P ₄ group. The combination of an amine with such a group can be carried out using the corresponding carboxylic acid or its reactive equivalent, under standard conditions for the formation of an amide bond or combination. A typical coupling reaction includes a suitable solvent, an amine in a concentration in the range of from about 0.01 to 10 M, preferably from about 0.1 to 1.0 M, the necessary carboxylic acid, base and peptide binding agent.

If the amine is used without isolation, the combination can be carried out in situ in the solvent of the reaction mixture used to obtain the amine, or in another solvent. The necessary carboxylic acid can be added to this reaction mixture, and the reaction is maintained at a temperature in the range of about 0 to 100 ° C, preferably in the range of about 20 to about 40 ° C. Then the base and the peptide binding reagent are added to the mixture, which is maintained at a temperature in the range of from about 0 to about 60 ° C, preferably in the range of from about 20 to about 40 ° C. The base is typically a tertiary amine base such as triethylamine, diisopropylethylamine, N-methylmorpholine, DBU, DBN, N-methylimidazole, preferably triethylamine or diisopropylethylamine. The amount of base to be used is typically up to about 20 equivalents per equivalent of amine, preferably at least about 3 equivalents of base. Examples of peptide coupling reagents include DCC (dicyclohexylcarbodiimide), DIC (diisopropylcarbodiimide), di-n-toluoilkarbodiimid, BDP (1-benzotriazoldietilfosfat-1-cyclohexyl-3- (2-morfoliniletil) carbodiimide), EDC (1- (3-dimethylaminopropyl -3-ethylcarbodiimide), cyanuric acid fluoride, cyanuric acid chloride, TFFH (tetramethyl fluoroformidinidium hexafluorophosphate), DPPA (diphenylphosphorazidate), BOP (benzotriazole-1-yloxyl-trisulfonate) -dimethyl-1-ylphosphoride N, N, N ', N'-tetramethyluronium), TBTU (tetrafluoroborate O-benzotriazol-1-yl-N, N, N ', N'-tetramethyluronium), TSTU (tetrafluoroborate O- (N-succinimidyl) -N, N, N', N'-tetramethyluronium), HATU ( N - [((dimethylamino) -1-H-1,2,3-triazolo [4,5,6] -pyridin-1-ylmethylene] -N-methylmethanamine, N-oxide hexafluorophosphate, BOP-Cl (bis chloride 2-oxo-3-oxazolidinyl) phosphinic acid), PyBOP (tetrafluorophosphate (1-H-1,2,3-benzotriazol-1-yloxy) -tris (pyrrolidino) phosphonium), BrOP (bromtris (dimethylamino) phosphonium hexafluorophosphate), DEPBT (3- (diethoxyphosphoryloxy) -1,2,3-benzotriazin-4 (3H) -one), PyBrOP (bromtris (pyrrolidino) phosphonium hexafluorophosphate). EDC, HOAT, BOP-Cl and PyBrOP are preferred peptide binding reagents. The amount of binding reagent is in the range of about 1.0 to about 10.0 equivalents. Optional reagents that can be used in the amide bond formation reaction include DMAP (4-dimethylaminopyridine) or active ester reagents such as HOBT (1-hydroxybenzotriazole), HOAT (hydroxyazabenzotriazole), HOSu (hydroxysuccinimide), HONB (endo-N-hydroxyhydroxy) -5-norbornene-2,3-dicarboxamide), in an amount ranging from about 1.0 to about 10.0 equivalents.

Alternatively, the amine can be treated with a reactive equivalent of R ₁ carboxylic acid, such as P ₂ -, P ₃ -P ₂ - or P ₄ -P ₃ -P ₂ -C (= O) X ¹ , where -C (= O) X ¹ represents a group that is more reactive than COOH in the coupling reaction. Examples of —C (═O) X ¹ groups include groups where X ¹ is Cl, F, OC (═O) R (R = aliphatic or aryl), —SH, SR, —SAr, or —SeAr. The acid and amine protecting groups used in the present invention are known in the art (see, for example, TW Greene & PGM Wutz, Protective Groups in Organic Synthesis, 3rd Edition, John Wiley & Sons, Inc. (1999) and earlier editions of this book).

Various chemical groups are known that can be used as P ₃ -P ₂ , part of a protease inhibitor. Examples of such P ₃ -P ₂ groups are included in US application No. 60/709964, which is also incorporated into this application by reference in its entirety.

Other methods well known in the art can also be used to implement the methods of the present invention and even to prepare the compounds of the present invention. See, for example, WO 07/022459 A2, which is incorporated herein by reference in its entirety.

III. Examples

The following examples are intended solely for illustration and should not be construed as in any way limiting the scope of the present invention.

Example 1: 3-propyloxyran-2-carboxylic acid

The flask equipped with an overhead stirrer, thermometer and dropping funnel was placed in a nitrogen atmosphere, then trans-2-hexenoic acid (69.8 g, 611 mmol), water (420 ml) and acetone (420 ml) were charged. Then sodium bicarbonate (NaHCO ₃ , 224 g, 2.66 mol) was added in portions, while maintaining the reaction temperature at 25 ± 5 ° C. After all of the sodium bicarbonate was added, a solution of OXONE® (454 g, 738 mmol) in 4 × 10 ^-4 M disodium salt of ethylenediaminetetraacetic acid dehydrate (Na ₂ EDTA; 1.32 L) was loaded into a dropping funnel and added over 90 minutes, while maintaining the reaction temperature at 25 ± 5 ° C and a pH in the range of 9.5-7.5. The reaction mixture was then left to stir for 16 hours, after which HPLC analysis showed the absence of any (E) -hex-2-enoic acid. The mixture was cooled to 0 ± 5 ° C, acidified to pH 2 using 6 N. HCl solution (515 ml, 2.8 mol) and was extracted with ethyl acetate (EtOAc; 3 × 250 ml). The combined organic phases were dried over sodium sulfate (Na ₂ SO ₄ ), filtered, then concentrated under reduced pressure to obtain the title compound (60.4 g, 76%) as a yellow oil.

¹ H-NMR (500 MHz, d _6- DMSO) δ 12.88 (br s, 1H), 3.21 (s, 1H), 3.06-3.03 (m, 1H), 1.58 -1.36 (m, 4H), 0.91 (t, J = 7.5 Hz, 3H).

Example 2: N-cyclopropyl-3-propyloxyran-2-carboxamide

The flask equipped with an overhead stirrer, a thermometer and a dropping funnel was placed in a nitrogen atmosphere, then the acid obtained in Example 1 (20.0 g, 154 mmol) and isopropyl acetate (IPAc; 200 ml) were charged and then cooled to 0 ± 5 ° C. 4-methylmorpholine (NMM, 154 ml, 17 ml) was loaded into a dropping funnel, then added while maintaining the temperature at 0 ± 5 ° C. After the addition was completed, the dropping funnel was washed with IPAc (10 ml) and then isobutyl chloroformate (IBCF, 137 mmol, 19.5 ml) was added, which was added while maintaining the temperature at 0 ± 5 ° C. The reaction mixture was stirred at 0 ± 5 ° C for 90 minutes, after which a solution of cyclopropylamine (154 mmol, 10.7) in IPAc (80 ml) was added, while maintaining the temperature at 0 ± 5 ° C. Upon completion of the addition, the reaction mixture was heated to 25 ± 5 ° C and allowed to stir for 18 hours. Sodium hydroxide (231 ml, 1.0 N) was added, and the biphasic mixture was stirred vigorously for 30 minutes, then the layers were separated. The organic phase was then washed with HCl (231 ml, 1.0 N). The combined organic phases were dried over sodium sulfate (Na ₂ SO ₄ ), filtered and concentrated under reduced pressure to obtain the title compound (19.5 g, 75%) as an orange oil.

¹ H-NMR (500 MHz, d _6- DMSO) 7.97 (br s, 1H), 3.10 (d, J = 1.9 Hz, 1H), 2.99-2.95 (m, 1H), 2.67-2.61 (m, 1H), 1.60-1.36 (m, 4H), 0.90 (t, J = 7.3 Hz, 3H), 0.62-0 58 (m, 2H), 0.47-0.43 (m, 2H).

Example 3: Alternative Preparation of N-cyclopropyl-3-propyloxyran-2-carboxamide

A flask equipped with a mechanical stirrer, a thermometer and a dropping funnel was placed in a nitrogen atmosphere, then the acid of Example 1 (5.0 g, 38 mmol), N- (3-dimethylaminopropyl) -N'-ethylcarbodiimide hydrochloride (EDCI; 8.1) were charged g, 42 mmol), 1-hydroxybenzotriazole hydrate (HOBt; 5.7 g, 42 mmol) and N, N-dimethylformamide (DMF; 50 ml), then cooled to 0 ± 5 ° C. NMM (5.9 ml, 54 mmol) was charged into a dropping funnel, which was then added to the reaction mixture, while maintaining the temperature at 0 ± 5 ° C. The mixture was stirred for 30 minutes, then cyclopropylamine (2.9 ml, 42 mmol) was added and the reaction mixture was allowed to warm to 25 ± 5 ° C for 16 hours. Hydrochloric acid (50 ml, 1.0 N) and IPAc (50 ml) were added, and then the mixture was stirred for another 30 minutes. All contents were transferred to a separatory funnel, the layers were separated, then the organic layer was washed successively with HCl (50 ml, 1.0 N), saturated aqueous NaHCO ₃ (2 × 50 ml) and saturated saline (2 × 50 ml). The combined organic phases were dried over sodium sulfate (Na ₂ SO ₄ ), filtered, then concentrated under reduced pressure to obtain the title amide (3.2 g, 50%) as an orange oil.

Example 4. Trans-N-cyclopropyl-2-hexenamide

The flask equipped with an overhead stirrer, thermometer and dropping funnel was placed in a nitrogen atmosphere, then charged with (E) -hex-2-enoic acid (89.8 g, 787 mmol), EDCI (158.3 g, 826 mmol), HOBt (112.0 g, 826 mmol) and IPAc (890 ml), then cooled to 0 ± 5 ° C. NMM (99.1 ml, 1.6 mol) was charged into a dropping funnel, which was then added to the reaction mixture, while maintaining the temperature at 0 ± 5 ° C. The mixture was stirred for 30 minutes, then cyclopropylamine (60.0 ml, 866 mmol) was added and the reaction mixture was allowed to warm to 25 ± 5 ° C for 16 hours. The reaction mixture was washed with hydrochloric acid (500 ml, 1.0 N) and the mixture was vigorously stirred for 30 minutes, then allowed to stand for 30 minutes; the layers were separated and the washing procedure was repeated. Sodium hydroxide (500 ml, 1.0 N) was added and then the mixture was vigorously stirred for 30 minutes, then allowed to stand for 30 minutes; the layers were separated and the washing procedure was repeated. Water (500 ml) was added and then the mixture was vigorously stirred for 30 minutes, then allowed to stand for 30 minutes; the layers were separated and the washing procedure was repeated. The combined organic phases were concentrated under reduced pressure to 1/3 of the original volume, then IPAc (600 ml) was added; this procedure was repeated twice, with the formation of a white precipitate. The suspension was then concentrated at atmospheric pressure to 2/3 of the original volume, then cooled to 50 ± 5 ° C. N-heptane (890 ml) was slowly added, while the reaction mixture was cooled to -5 ± 5 ° C and kept at this temperature for 4 hours. The solid was filtered, washed with cold n-heptane (2 × 250 ml) and dried to give the title amide (82.4 g, 68%) as fine white solid particles.

¹ H-NMR (500 MHz, d _6- DMSO) 7.89 (s, 1H), 6.58 (dt, J = 15.2, 7.0 Hz, 1H), 5.80 (dt, J = 15.2, 1.3 Hz, 1H), 2.70-2.65 (m, 1H), 2.12-2.06 (m, 2H), 1.44-1.37 (m, 2H) 0.88 (t, J = 7.3 Hz, 3H); 0.64-0.60 (m, 2H); 0.42-0.38 (m, 2H).

Example 5: N-cyclopropyl-3-propyloxyran-2-carboxamide

The flask equipped with an overhead stirrer, thermometer and dropping funnel was placed in a nitrogen atmosphere, then tert-butyl hydroperoxide (TBHP; 95 ml, 5.5 M, 522 mmol) and tetrahydrofuran (THF; 200 ml) were charged. The reaction mixture was cooled to -20 ± 5 ° C and loaded into a dropping funnel of n-butyllithium (n-BuLi; 235 ml, 2.5 M, 587 mmol) and was slowly added, while maintaining the reaction temperature below -5 ± 5 ° C . Upon completion of the addition, the reaction mixture was heated to 0 ± 5 ° C and the amide of Example 4 (19.80 g, 130 mmol) in THF (20 ml) was added while maintaining the temperature at 0 ± 5 ° C, after which the temperature was raised to 25 ± 5 ° C and the reaction mixture was stirred for 12 hours. After that, IPAc (200 ml) and saturated aqueous sodium hydrogen sulfite (200 ml) were added and the reaction mixture was stirred for 60 minutes. The layers were separated and the aqueous layer was extracted with IPAc (twice, 75 ml each time). The combined organic phases were dried over sodium sulfate (Na ₂ SO ₄ ), filtered and concentrated under reduced pressure to obtain the title compound (21.87 g, 99%).

Example 6: N-cyclopropyl-3-propyloxyran-2-carboxamide

The flask equipped with a mechanical stirrer, thermometer and dropping funnel was placed in a nitrogen atmosphere, then samarium (III) isopropoxide (Sm (Oi-Pr) ₃ , 430 mg, 1.3 mmol), triphenylarsine oxide (Ph ₃ As = 0; 420 mg, 1.3 mmol), S - (-) 1,1'-bi-2-naphthol ((S) -BINOL), 370 mg, 1.3 mmol), 4 Å molecular sieves (13 g) and THF (20 ml), then was stirred for 30 minutes at a temperature of 25 ± 5 ° C. Then tert-butyl hydroperoxide (2.8 ml, 5.5 M, 16 mmol) was added. The mixture was stirred for 30 minutes at 25 ± 5 ° C, then the amide of Example 4 (2.0 g, 13 mmol) in THF (2.0 ml) was added. The reaction mixture was stirred for 14 hours, after which the reaction was 95% complete as determined by HPLC.

Example 7: N-cyclopropyl-3-propyloxyran-2-carboxamide

Into a three-necked 250 ml round bottom flask equipped with a mechanical stirrer and containing (E) -N-cyclopropylhex-2-enamide (10.0 g, 65.3 mmol) and urea-hydrogen peroxide (UHP) (25.0 g, 4 , 0 equiv.) In CH ₂ Cl ₂ (100 ml, 10 vol.), Trifluoroacetic anhydride (41.1 g, 27.2 ml, 3.0 equiv.) Was added at 0 ° C. The reaction mixture was heated to a temperature of 35 ± 5 ° C and was stirred for 2 hours. After the reaction mixture was cooled to room temperature, another aliquot of trifluoroacetic anhydride (13.7 g, 9.0 ml, 1.0 equiv.) Was added. The reaction mixture was again heated to a temperature of 35 ± 5 ° C and stirred for another 3 hours.

The reaction mixture was then again cooled to 0 ° C and quenched by slow addition of a saturated solution of NaHCO ₃ (5 vol.) And stirring for 30 minutes. The organic layer was separated and the aqueous layer was extracted with CH ₂ Cl ₂ (50 ml, 5 vol.). The combined organic layer was dried and evaporated to give 10.0 g (90%) of the crude product, N-cyclopropyl-3-propyloxyran-2-carboxamide, as a pale yellow oil. The crude product was used in the next step without further purification.

Example 8: 3-azido-N-cyclopropyl-2-hydroxyhexanamide

The flask equipped with an overhead stirrer, thermometer and reflux condenser was placed in a nitrogen atmosphere and then the epoxide of Example 5 (20.0 g, 118 mmol), sodium azide (NaN ₃ ; 31.0 g, 473 mmol), magnesium sulfate ( MgSO ₄ ; 14.0 g, 118 mmol) and methanol (MeOH; 200 ml). The mixture was heated to 65 ± 5 ° C for 2 hours, then cooled to 25 ± 5 ° C and filtered through a pad of Celite 545. The solvent was removed under reduced pressure to obtain a viscous oil, which was transferred for absorption in IPAc (250 ml) , then washed with water (3 × 250 ml). The organic phase was dried over sodium sulfate (Na ₂ SO ₄ ), filtered and concentrated under reduced pressure to obtain the title compound (15.1 g, 60%) as a white solid.

¹ H-NMR (500 MHz, d _6- DMSO) 7.87 (s, 1H), 5.97 (d, J = 6.0 1H), 4.02 (dt, J = 6.0, 3, 8 Hz, 1H), 2.70-2.65 (m, 1H), 1.60-1.20 (m, 4H), 0.88 (t, J = 7.0 Hz, 3H), 0, 63-0.58 (m, 2H), 0.51-0.46 (m, 2H).

Example 9: 3-amino-N-cyclopropyl-2-hydroxyhexanamide

The azide of example 7 (15.1 g, 71.3 mmol), Pd / C (1.5 g, 5% wt., Moisture content 50%) and MeOH (150 ml) were loaded into a high-pressure apparatus, then purged with nitrogen gas within 5 minutes. The vessel was hermetically sealed, a pressure of up to 1 bar was created using nitrogen gas, followed by the release of gas, three times. The same procedure was repeated with hydrogen gas. After a third hydrogen purge, 3 bar of hydrogen was charged into the vessel. Stirring was started and the temperature was maintained at 25 ± 5 ° C. The reaction mixture was stirred in this manner for 14 hours, after which the reaction mixture was filtered through a pad of Celite 545 and the solvent was removed to give the crude amino alcohol (8.48 g) as a yellow solid. Acetonitrile (ACN; 150 ml) was added to this material, and the reaction mixture was heated to reflux, with all solids dissolved. The mixture was then cooled to 25 ± 5 ° C and the resulting white needle crystals were collected, washed with cold ACN and dried to give purified amino alcohol (4.87 g).

¹ H-NMR (500 MHz, d _6- DMSO) 8.05 (br s, 3H), 4.20 (d, J = 3.2, 1H), 3.42-3.34 (m, 1H ), 2.71-2.65 (m, 1H), 1.51-1.20 (m, 4H), 1.17 (d, J = 6.5 Hz, 1H), 0.83 (t, J = 7.6 Hz, 3H), 0.64-0.60 (m, 2H), 0.54-0.49 (m, 2H).

Example 10: 3-amino-N-cyclopropyl-2-hydroxyhexanamide, salt of L-tartaric acid

To a racemic mixture of 3-amino-N-cyclopropyl-2-hydroxyhexanamide (100 mg, 0.53 mmol) in MeOH (1 ml) was added L-tartaric acid (39.7 mg, 0.26 mmol) in MeOH (20 μl ) and the mixture was cooled to 0 ± 5 ° C. After 48 hours at 0 ± 5 ° C, a white precipitate formed, which was collected, washed with methyl tert-butyl ether (2 × 5 ml), then dried to obtain the title compound. Chiral HPLC analysis and comparison with an authentic sample of the chiral hydrochloride salt of an amino alcohol showed that the title compound was obtained with 62% ee.

Example 11: 3-amino-N-cyclopropyl-2-hydroxyhexanamide, deoxycholic acid salt

In a three-necked 250 ml round bottom flask equipped with a mechanical stirrer and containing racemic 3-amino-N-cyclopropyl-2-hydroxyhexanamide (10.0 g, 53.69 mmol) in THF (100 ml), deoxycholic acid (15.8) was charged g, 40.27 mmol, 0.75 equiv.). The reaction mixture was stirred and heated at 65 ± 5 ° C for 2 hours. The resulting homogeneous mixture was allowed to cool to a temperature in the range of 22-25 ° C for one hour and was maintained at this temperature for 4 hours. Precipitated solids were collected by filtration, washed with THF (10 ml), dried overnight to obtain 12.2 g of 3-amino-N-cyclopropyl-2-hydroxyhexanamide in the form of a deoxycholic acid salt (41%, enantiomeric ratio (ER) = 3: 97) as a white solid.

Example 12: 3-amino-N-cyclopropyl-2-hydroxyhexanamide, hydrochloric acid salt

In a three-necked 250-ml round-bottom flask equipped with a mechanical stirrer and containing a mixture of the deoxycholic acid salt obtained in Example 11 in 2-propanol (62 ml) was added 5-6 N. a solution of HCl in isopropyl alcohol (66 ml, 3 equiv.) with stirring. The resulting solution was heated at a temperature of 75 ± 5 ° C for one hour and allowed to cool to a temperature in the range of 22-25 ° C for 1 hour and maintained at this temperature for 2 hours. Precipitated solids were collected by filtration, washed with 2-propanol (12 ml, 1 vol.), Dried overnight to obtain 7.2 g of 3-amino-N-cyclopropyl-2-hydroxyhexanamide in the form of a hydrochloric acid salt (75%, enantiomeric ratio (ER) = 0.05: 99.95) as a white solid.

Example 13. Obtaining (1S, 3aR, 6aS) -2 - ((S) -2 - ((S) -2-cyclohexyl-2- (pyrazine-2-carboxamido) acetamido) -3,3-dimethylbutanoyl) -N - ((S) -1- (cyclopropylamino) -1,2-dioxo-hexan-3-yl) octahydrocyclopenta [c] pyrrole-1-carboxamide

(соединение vii, представленное ниже) Stage a: Getting

(compound vii below)

The above sult vi are obtained by known methods, such as those described in Y. Elemes and U. Ragnarsson, J. of Chem. Soc, Perkin 1, 1996, 6, p. 537; W. Oppolzer et al., Helv. Chim. Acta., 1994, 25: 2363), using the corresponding unsubstituted sultam and propyl iodide.

Compound vi (17.32 g, 45.8 mmol) and THF (229 ml) were charged into a 500 ml round bottom flask equipped with a magnetic stirrer and an inlet for N ₂ . The resulting solution was cooled to −78 ° C. and n-BuLi (31.5 ml of a solution of 1.6 M in hexane, 50.3 mmol) was added using a syringe pump over 1 hour. The resulting yellow solution was aged for 30 minutes, and then a solution of HPMA (56 ml) and n-PrI (13.4 ml, 137 mmol) were added over 30 minutes. The mixture was allowed to warm to room temperature over 8 hours. The mixture was cooled to −20 ° C. and H ₂ O (50 ml) was added. The reaction mixture was extracted with EtOAc (400 ml) and the organic phases were dried over MgSO ₄ and concentrated to give 61.3 g of a crude oil. Chromatography on 500 g of silica gel eluting with a 2: 1 heptane / EtOAc mixture followed by concentration of the enriched fraction gave 20.35 g of a white solid. This material was recrystallized from EtOH (210 ml) to give compound vii as a white crystalline solid.

Stage b: Obtaining (S) -2- (benzyloxycarbonylamino) -pentanoic acid (compound viii above)

Compound vii (15.39 g, 32.1 mmol) was combined with THF (100 ml) and 1 N. HCl solution (50 ml). The resulting emulsion was stirred overnight at room temperature and then concentrated under reduced pressure to obtain a viscous oil. The resulting oil was dissolved in THF (100 ml), water (25 ml) and LiOH (3.08 g, 128 mmol) were added. The resulting solution was stirred overnight at room temperature and then concentrated to remove THF to give a cloudy, light yellow emulsion. The emulsion was diluted with water (25 ml) and was extracted with CH ₂ Cl ₂ (3 × 50 ml). The aqueous phase was diluted with THF (200 ml) and then cooled to 0 ° C with rapid stirring, and CBZ-Cl (7.6 ml, 54 mmol) was added dropwise over 15 minutes. After 1 hour at 0 ° C, THF was removed in vacuo and the residue was acidified by adding 50 ml of 1 N. HCl solution. The mixture was extracted with EtOAc (3 × 100 ml) and the organic phase was dried over Na ₂ SO ₄ and concentrated to give an oil. The resulting residue was dissolved in EtOAc (25 ml) and heptane (150 ml), a seed crystal was added and stirred overnight at room temperature. The solids were collected on a frit, washed with heptane (30 ml) and dried in air to give compound viii.

Stage c: Obtaining (S) -2- (benzyloxycarbonylamino) -pentanoic acid

As shown below, the title compound is obtained by hydrolysis of sultam, which is a product of step a, and converting the resulting free amino acid into its Cbz derivative by known methods (see, for example, W. Green, PGM Wuts, Protective Groups in Organic Synthesis, Wiley Interscience, New York, 1999).

Step d: Preparation of (S) -benzyl 1- (methoxy (methyl) amino) -1-oxo-2-pentan-2-ylcarbamate

To a flask containing 1.0 g of (S) -2- (benzyloxycarbonylamino) -pentanoic acid (3.97 mmol) in 20 mL of dichloromethane maintained at ⁰ ° C, was added 3.0 eq. N-methylmorpholine (700 μl), 1.5 eq. N, O-dimethylhydroxylamine hydrochloride (581 mg) and 1.5 eq. EDCI (1.14 g). The reaction mixture was stirred overnight at a temperature of from ⁰ ° C to room temperature. The reaction mixture was then diluted in dichloromethane and washed with HCl solution (1 N) and brine. The organic layer was dried over MgSO ₄ . The crude mixture was purified by flash chromatography (ethyl acetate 15-75% in hexane) to give the title compound.

Step e: Preparation of (S) -benzyl 1-oxo-2-pentan-2-ylcarbamate

Using the procedure described in WO 02/18369, the Cbz-protected amino acid of step d was converted to the title compound. Specifically, in a flask containing 1.0 eq. (S) -benzyl 1- (methoxy (methyl) amino) -1-oxo-2-pentan-2-ylcarbamate (810 mg, 2.75 mmol) in 10 ml of anhydrous THF, maintained at 0 ° C (on ice bath), 1.7 equiv. lithium borohydride solution (1.0 M) (4.67 ml). After about 10 minutes, the ice bath was removed and the reaction was continued for one hour. The reaction was quenched at 0 ° C by adding 5 ml of KHSO ₄ solution (10%). The solution was then diluted by adding 10 ml of HCl (1 N.). The mixture was stirred for 30 minutes, then extracted 3 times with dichloromethane. The organic phases were combined and washed with HCl solution (1N), water and brine. The organic phase was then dried over MgSO ₄ and the volatiles were evaporated. Aldehyde was used as such in the next step.

Stage f: Obtaining benzyl (3S) -1- (cyclopropylamino) -2-hydroxy-1-oxohexan-3-ylcarbamate

Cyclopropylisocyanide was prepared according to the scheme below.

Specifically, cyclopropylisonitrile was combined with the aldehyde product of step d to obtain the title compound as described in J. E. Semple et al., Org. Lett., 2000, 2 (18), p. 2769; Lumma W., J. Org. Chem., 1981, 46, 3668.

Step g: Preparation of (3S) -3-amino-N-cyclopropyl-2-hydroxyhexanamide

The hydrogenolysis of the Cbz compound of step e was carried out using a palladium-carbon catalyst in the presence of hydrogen to obtain the title compound. The diagrams below show stages d, e, f, and g.

Step h: Preparation of (1S, 3aR, 6aS) -2 - ((S) -2 - ((S) -2-cyclohexyl-2- (pyrazine-2-carboxamido) acetamido) -3,3-dimethylbutanoyl) -N - ((3S) -1- (cyclopropylamino) -2-hydroxy-1-oxohexan-3-yl) octahydrocyclopenta [c] pyrrole-1-carboxamide

The title compound was obtained from the hydroxy aminoamide product of step g by condensation with a suitable acid in the presence of a coupling agent, such as, for example, EDCI and HOSu. Specifically, in a flask containing 1.2 eq. (1S, 3aR, 6aS) -2 - ((S) -2 - ((S) -2-cyclohexyl-2- (pyrazine-2-carboxamido) acetamido) -3,3-dimethylbutanoyl) octahydrocyclopenta [c] pyrrole- 1-carboxylic acid (1.59 g) in 20 ml of DMF, 2.5 equiv. diisopropylamine (980 μl), 1.2 eq. N-hydroxybenzotriazole hydrate (411 mg) and 1.3 eq. EDCI (558 mg). After 15 minutes stirring at room temperature, 1.0 eq. (3S) -3-amino-N-cyclopropyl-2-hydroxyhexanamide hydrochloride (500 mg). After another 24 hours, the reaction mixture was diluted in 400 ml of ethyl acetate. The organic phase of the mixture was washed with HCl (1 N), water, saturated sodium bicarbonate, brine, and then dried over MgSO ₄ . The crude product was purified by chromatography on silica (ethyl acetate 70-100% in hexane) to give the title compound.

Step i: Preparation of (1S, 3aR, 6aS) -2 - ((S) -2 - ((S) -2-cyclohexyl-2- (pyrazine-2-carboxamido) acetamido) -3,3-dimethylbutanoyl) -N - ((S) -1- (cyclopropylamino) -1,2-dioxohexan-3-yl) octahydrocyclopenta [c] pyrrole-1-carboxamide

The title compound was prepared by oxidizing the product of step h using a suitable oxidizing agent, such as periodinan Dess Martin or TEMPO, and sodium hypochlorite. Specifically, in a flask containing 1.31 g of (1S, 3aR, 6aS) -2 - ((S) -2 - ((S) -2-cyclohexyl-2- (pyrazine-2-carboxamido) acetamido) -3, 3-dimethylbutanoyl) -N - ((3S) -1- (cyclopropylamino) -2-hydroxy-1-oxohexan-3-yl) octahydrocyclopenta [c] pyrrole-1-carboxamide in 40 ml of dichloromethane, was added at room temperature 1, 06 g periodinan Dess Martin. After 2 hours of stirring, 50 ml of sodium bisulfite (1 N) was added and the mixture was stirred for 30 minutes. The 2 phases were separated, the organic phase was washed with water twice, with brine and dried over Na ₂ SO ₄ . The crude product was purified by chromatography on silica (ethyl acetate 20-100% in hexane) to give the title compound. The diastereomeric ratio was determined using normal phase chiral HPLC.

The diagram below shows the reactions of stage g and stage h.

Example 14: Preparation of (2S, 3S) -3-amino-N-cyclopropyl-2-hydroxyhexanamide hydrochloride

Stage 1: Recovery (trans-2-hexen-1-ol)

In a three-necked 250 ml round bottom flask equipped with a mechanical stirrer and reflux condenser, 2-hexin-1-ol (10 g, 0.1 mol) and THF (100 ml, 10 vol.) Were charged. The resulting mixture was cooled to 0 ± 5 ° C and then Red-Al (65% in toluene, 32 ml, 1.6 eq.) Was slowly added in a nitrogen atmosphere at a temperature ranging from 0 ° C to 20 ° C. The resulting mixture was allowed to warm to 25 ° C and stirred for 5 hours. The reaction mixture was cooled to −5 ± 5 ° C and H ₂ O (8.2 g, 4 equiv.) Was added dropwise at a temperature ranging from 0 ° C to 15 ° C. To the resulting mixture were added IPAC (50 ml, 5 vol.) And a saturated solution of NH ₄ Cl (50 ml, 5 vol.). After the mixture was stirred for 10 minutes, the white solid formed was filtered off. The organic layer was separated from the filtrate and the aqueous layer was extracted with IPAC (30 ml, 3 vol). The organic layers were combined and washed with water (30 ml, 3 vol.), Dried over MgSO ₄ and concentrated to give a product, i.e. Compounds 2. The crude product was used in the next step without further purification.

Stage 2: Oxidation: MnO ₂ (trans-2-hexene-1-al)

In a three-necked 250-ml round bottom flask equipped with a mechanical stirrer containing 2-hexen-1-ol-3d (10 g, 0.1 mol) in CH ₂ Cl ₂ (150 ml, 15 vol.), Activated MnO ₂ ( 87 g, 10 equiv.) At room temperature. After vigorous stirring for 1 hour, another portion of MnO ₂ (16 g, 2 equiv.) Was added and shaking continued for 4 hours. The reaction solution was filtered through a layer of Cilit®. The solvent was removed in vacuo (25 ° C, 100 mmHg) to give a crude aldehyde product (i.e., compound 3). The crude product was used in the next step without further purification.

Stage 3: Oxidation: NaClO ₂ (trans-2-hexenoic acid)

In a three-necked 500-ml round-bottom flask equipped with a mechanical stirrer and reflux condenser, 2-hexene-1-al-3d (10 g, 0.1 mol), tert-BuOH (90 ml, 9 vol.) And 2-methyl were charged -2-butene (30 ml, 3 vol.). To the resulting solution was added a freshly prepared aqueous solution of NaClO ₂ (27.4 g, 3 equiv.) And NaH ₂ PO ₄ (62.9 g, 4 equiv.) In water (200 ml) over 30 minutes. The reaction mixture was stirred at room temperature for 2 hours. The reaction solution was cooled to 0 ° C. and a saturated aqueous solution of Na ₂ SO _{3 was} added thereto until the reaction mixture became colorless. Stirring was stopped, the organic layer was separated, and the aqueous layer was extracted with EtOAc (3 vol. × 3). The organic layers were combined and concentrated in vacuo until a total volume of 3 vol. The resulting solution was extracted with 1 N. NaOH solution (3 vol. × 3) and the remaining organic layer was poured. The combined aqueous solution was acidified with 6 N. HCl solution until the pH reaches 1.0. The solution was extracted with CH ₂ Cl ₂ (3 vol. × 5). The combined organic layers were dried over MgSO ₄ and concentrated to give the product (i.e., compound 4).

Stage 4: Amidation of ((E) -N-cyclopropylhex-2-enamide)

In a three-necked 250-ml round-bottom flask equipped with a mechanical stirrer and reflux condenser, 2-hexenoic acid-3d (10 g, 0.09 mol), IBCF (13 g, 1.1 eq.) In CH ₂ Cl ₂ (100 ml, 10 vol.). The resulting solution was cooled to 0 ° C and NMM (13.2 g, 1.5 equiv) was slowly added, while controlling the temperature in the range from 0 to 20 ° C. Then the mixture was allowed to warm to room temperature and was stirred for 1 hour. Cyclopropylamine (5.9 g, 1.2 equiv.) Was added to the resulting solution, and the solution was stirred for 2 hours. The reaction mixture was washed with 1 N. NaOH solution (3 vol. × 2), 1 N. HCl solution (3 vol. × 2) and saturated saline (3 vol.) and water (3 vol.). The organic layer was dried over MgSO ₄ and concentrated to give the crude product as an oil. The crude product was dissolved with heptane (5 vol.) And cooled to -78 ° C with stirring. The precipitated solid was filtered and dried to give a product (i.e., compound 5).

Stage 5: Epoxidation (N-cyclopropyl-3-propyloxyran-2-carboxamide)

Into a three-necked 250-ml round bottom flask equipped with a mechanical stirrer and containing (E) -N-cyclopropylhex-2-enamide-3d 5 (10 g, 0.06 mol), urea-hydrogen peroxide (25 g, 4 equiv.) And p-TsOH (12.3 g, 1 equiv.) in CH ₂ Cl ₂ (100 ml, 10 vol.) at 0 ° C was added trifluoroacetic anhydride (40.9 g, 3 equiv.) in CH ₂ Cl ₂ (50 ml, 5 vol.) for 30 minutes. The reaction mixture was heated to a temperature of 40 ± 5 ° C and stirred for 3 hours. After cooling to 0 ° C, the reaction mixture was quenched by slow addition of 6 N. NaOH solution (100 ml, 10 vol.) and was stirred for 30 minutes. The organic layer was separated and washed with saturated saline (5 vol.) And water (5 vol.). The washed organic layer was dried over MgSO ₄ and the solvent was evaporated to give an epoxy product (i.e., compound 6), which was used in the next step without further purification.

Stage 6: Formation of azide (3-azido-N-cyclopropyl-2-hydroxyhexanamide)

Into a three-necked 250-ml round bottom flask equipped with a mechanical stirrer and reflux condenser containing epoxide-3d 6 (10 g, 0.06 mol) and anhydrous magnesium sulfate (14.1 g, 2.0 equiv.) In MeOH (100 ml 10 vol.), Sodium azide (15.3 g, 4.0 eq.) Was added in one portion. The resulting mixture was heated to a temperature of 65 ± 5 ° C and stirred for 5 hours. The reaction mixture was cooled to room temperature, IPAC (100 ml, 10 vol) was added and the mixture was stirred for another 10 minutes. The mixture was filtered through a layer of Cilit® to remove insoluble salts and the resulting clear solution was concentrated to 3 vol. IPAC (170 ml, 17 vol) was added to the resulting solution, and the mixture was stirred for another 10 minutes. Again, the solution was filtered through a pad of Celite® to give the product, azide-3d (i.e. compound 7), as a solution in IPAC (about 200 ml), which was used in the next step without further purification.

Stage 7: Hydrogenation (racemic product)

In a 500 ml hydrogenation reactor, which is an autoclave equipped with a mechanical stirrer, containing azide-3d (i.e. compound 7) (200 ml, 0.05 mol), IPd obtained in the previous step was charged with Pd / C (10 % Pd, water content 50%, 0.8 g). Nitrogen (1.0 atm) was introduced into the solution and then released three times, then hydrogen (3.0 atm) was introduced and released three times. Hydrogen (3 atm) was introduced into the resulting solution and stirred for 5 hours. After the release of hydrogen gas, the solution was purged with nitrogen for 5 minutes. MeOH (30 ml, 3 vol) was added to the resulting solution, and the reaction mixture was heated to a temperature of 50 ± 5 ° C. The reaction mixture was filtered through a layer of Cilit® to obtain a clear solution. The product was isolated by concentrating the solution at a temperature of 20 ± 5 ° C until 3 vol. solution. The solid was collected by filtration, washed (IPAC, 3 vol.) And dried to give the product (i.e., compound 8).

Step 8: Separation of 3-amino-N-cyclopropyl-2-hydroxyhexanamide

I. Salt Formation

Deoxycholic acid (15.7 g, 0.75 equiv) was charged into a three-necked 250 ml round bottom flask equipped with a mechanical stirrer and containing racemic 3-amino-N-cyclopropyl-2-hydroxyhexanamide (10 g, 0.05 mol) in THF (100 ml, 10 vol.). The reaction mixture was heated to 65 ± 5 ° C and stirred for 1 hour at this temperature. The resulting homogeneous mixture was cooled to a temperature of 23 ± 2 ° C for 1 hour and left at a temperature in the indicated limits for 1 hour. Precipitated solids were collected by filtration, washed with THF (50 ml, 5 vol.) And dried to give a salt.

In a three-necked 250-ml round-bottom flask equipped with a mechanical stirrer, salt (obtained in the previous step) and 2-propanol (62 ml, 5 vol.) Were charged. The solution was heated to a temperature of 75 ± 5 ° C and 5-6 N was slowly added. a solution of HCl in IPA (12 ml, 3 equiv.) with vigorous stirring. The resulting solution was stirred at the indicated temperature for 1 hour and then cooled to a temperature of 23 ± 2 ° C. The reaction mixture was maintained at this temperature for 1 hour. Precipitated solids were collected by filtration, washed with 2-propanol (36 ml, 3 vol.), Dried to obtain (2S, 3S) -3-amino-N-cyclopropyl-2-hydroxyhexanamide hydrochloride (enantiomeric ratio = 0: 100).

Other embodiments

It should be understood that although the present invention has been presented in connection with its detailed description, the above description of the invention is intended to illustrate it and does not limit the scope of the present invention, which is determined by the scope of the attached claims. Other aspects, advantages and modifications are covered by the following claims.

Claims (29)

1. A method of obtaining an optically enriched salt of a compound of formula iii

with more than 55% enantiomeric excess, where
carbon atoms alpha and beta relative to the carboxy group are stereo centers;
R ₁ represents C ₁ -C ₆ alkyl;
R ' ₁ represents hydrogen;
R ′ ₂ represents —NHR ₂ ;
R ₂ represents C ₃ -C ₆ cycloalkyl;
comprising the following steps:
a) forming a salt of a compound of formula iii with an optionally optically active organic acid selected from L-tartaric acid, malic acid, diisopropylidengulonic acid and deoxycholic acid in a solvent, and
b) crystallization of the specified salt to obtain this salt with more than 55% enantiomeric excess. 2. The method according to claim 1, where R ₁ represents propyl and R ₂ represents cyclopropyl. 3. The method according to claim 2, where the solvent in stage (a) is methanol. 4. The method according to claim 3, where stage (a) is performed at room temperature. 5. The method according to claim 4, where stage (b) is performed at a temperature of 0 ± 5 ° C. 6. The method according to claim 2, where the solvent in step (a) is THF. 7. The method according to claim 6, where stage (a) is performed at room temperature. 8. The method according to claim 4, where stage (b) is performed at a temperature of 65 ± 5 ° C. 9. The method of claim 8, where stage (b) is performed at room temperature. 10. The method according to claim 1, further comprising the amination of a compound of formula ii

an amination agent, wherein the amination agent is an azide salt and the intermediate azido compound is reduced by hydrogenation to give a compound of formula iii

11. The method of claim 10, further comprising oxidizing the unsaturated compound of formula i

where RS is —NHR ₂ , using an oxidizing agent to give a compound of formula ii

moreover, the oxidizing agent is tert-butyl hydroperoxide, a mixture of samarium (III) isopropoxide, triphenylarsine oxide or urea-hydrogen peroxide. 12. The method of claim 10, wherein the oxidizing agent is tert-butyl hydroperoxide. 13. The method of claim 10, where the oxidizing agent is a mixture of samarium (III) isopropoxide, triphenylarsine oxide, S - (-) 1,1'-bi-2-naphthol and 4 Å molecular sieves. 14. The method of claim 10, wherein the oxidizing agent is urea-hydrogen peroxide in the presence of trifluoroacetic anhydride. 15. The method of obtaining the compounds of formula iii

where R ₁ represents C ₁ -C ₆ alkyl;
R ' ₁ represents hydrogen;
R ′ ₂ represents —NHR ₂ ;
R ₂ represents C ₃ -C ₆ cycloalkyl; and
the compound of formula iii has an enantiomeric excess of more than 55%, comprising the following steps:
a) oxidizing an unsaturated compound of formula i, wherein the oxidizing agent is tert-butyl hydroperoxide, a mixture of samarium (III) isopropoxide, triphenylarsine oxide, S - (-) 1,1'-bi-2-naphthol and 4 Å molecular sieves, or urea peroxide - hydrogen in the presence of trifluoroacetic anhydride,

to obtain the compounds of formula ii

b) reacting a compound of formula ii with an amination agent, wherein the amination agent is an azide salt and the intermediate azido compound is reduced by hydrogenation to give a compound of formula iii

c) salt formation of a compound of formula iii with an optically active organic acid selected from L-tartaric acid, malic acid, diisopropylidengulonic acid and deoxycholic acid in a solvent; and
d) crystallization of the specified salt to obtain this salt with more than 55% enantiomeric excess. 16. The method according to clause 15, where the compound of formula i is (2S, 3S) -3-amino-N-cyclopropyl-2-hydroxyhexanamide. 17. The method according to clause 15, where the solvent in stage (C) is methanol. 18. The method according to clause 15, where stage (C) is performed at room temperature. 19. The method according to clause 15, where stage (d) is performed at a temperature of 0 ± 5 ° C. 20. The method of claim 15, wherein the solvent in step (c) is THF. 21. The method according to claim 20, where stage (C) is performed at room temperature. 22. The method according to item 21, where stage (C) is performed at a temperature of 65 ± 5 ° C. 23. The method according to item 21, where stage (d) is performed at room temperature. 24. The method of claim 15, wherein the organic acid is L-tartaric acid. 25. The method according to clause 15, where the organic acid is a deoxycholic acid. 26. A compound that is N-cyclopropyl-3-propyloxyran-2-carboxamide. 27. The compound, which is 3-azido-N-cyclopropyl-2-hydroxyhexanamide. 28. A compound that is 3-amino-N-cyclopropyl-2-hydroxyhexanamide, a salt of L-tartaric acid. 29. A compound which is 3-amino-N-cyclopropyl-2-hydroxyhexanamide, a salt of deoxycholic acid.