KR20090101581A - The preparaton of alkenylazetidinone intermediates for carbapenems - Google Patents

Abstract

PURPOSE: A method for preparing an alkenyl azetidinone intermediate for carbapenem is provided to easily synthesize effective 1β-methyl carbapenem compound with low price. CONSTITUTION: A method for preparing an alkenyl azetidinone intermediate for carbapenem comprises: a step of preparation with 4(R)-acetoxyazetidinone as a starting material; a step of performing crotylation under the presence of chiral ligand, transition metal, and Lewis acid; and a step of producing 4-(alk-2-enyl)-2-azetidinone of the chemical formula 1. The chiral ligand is selected from cinchonine, cinchonidin, quinine, quinidine, norephedrin, O-acetylquinine, and O-acetylquinidine. The transition metal is selected from zinc or indium. The Lewis acid is selected from AgCl, PdCl, AgOTf, InCl3, ZnBr2, and Sc(OTf)3.

Description

Preparation of alkenyl azetidinone intermediates for carbapenems {THE PREPARATON OF ALKENYLAZETIDINONE INTERMEDIATES FOR CARBAPENEMS}

The present invention relates to a method for preparing alkenyl azetidinone intermediates for carbapenem, more specifically, represented by the following formula (1), to prepare 1β-methyl carbapenem used as an intermediate of carbapenem-type antibiotics It relates to a method for preparing 4- (alk-2-enyl) -2-azetidinone which is an azetidinone derivative.

Provided that R ₁ and R ₂ are each H and Me, and R ₃ is a hydrogen atom or a hydroxyl-protecting group.

Carbapenem-type antimicrobials are excellent antimicrobial agents that have strong antimicrobial activity against a broad spectrum of bacteria, from Gram-positive bacteria to Gram-negative bacteria, including Pseudomonas aeruginosa . Types of new antibacterial agents are being actively developed.

Carbapenem compounds usually have a carbapenem skeleton, such as thienamycin of formula (2).

However, carbapenem antimicrobials without substituents at position 1 are chemically unstable and, furthermore, are easily metabolized by Dehydropeptidase 1 in vivo ( Antimicrob. Agents Chemother. 1982, 22, 62. ; J. Antibiotics 1979, 32, 1.).

 To solve this problem, incorporation of beta-coordinated alkyl groups into position 1 improves the stability of these carbapenem derivatives and these derivatives can be used alone without the need to add a dehydropeptidase inhibitor. As a result, it can be converted to stereochemically very pure carbapenems.

Conventionally, the method for preparing 4- (alk-2-enyl) -2-azetidinone, which is a starting material for synthesizing 1β-methyl carbapenem, is non-stereospecific ( J. Org. Chem. , 50, 3438 , 1985), the steric chemistry of the product cannot be controlled, resulting in insufficient feasibility of the process, resulting in a low yield of the desired 1β-methyl carbapenem.

In other words, the R- and S-isomers of the 1β-methylcarbapenem-type derivatives having various substituents are obtained in a ratio of 1: 1, respectively, in a mixture with less useful R- isomers or at least a substantial amount of R- isomers. As prepared ( Chem. Pharm. Bull. , 39 (3), 663-671, 1991), it was difficult, costly and inefficient to separate the desired S-isomer from it.

Thus, the present inventors used 4- (alk-2-enyl) -2-azetidinone, i.e., (4R) -4-[(1S)-, with the target isomer as the main product so that the desired compound can be obtained in better yield. As a result of intensive efforts to prepare 1-methylallyl] -2-azetidinone {(4R) -4-[(1S) -1-Methylallyl] -2-azetidinone}, the desired isomer is up to three times higher than before. It was confirmed that it can be obtained and completed the present invention.

After all, the main object of the present invention is stereospecific for preparing the desired isomer of 4- (alk-2-enyl) -2-azetidinone, which is the main intermediate for preparing antimicrobial 1β-methyl carbapenem. To provide a method.

In order to achieve the above object, the present invention uses 4-acetoxyazetidinone (4 (R) -acetoxyazetidinone (I)) as a starting material, chiral ligand (Chiral Ligand), transition metal, Lewis acid (Lewis acid) It provides a method for the preparation of beta (β-form) 4- (alk-2-enyl) -2-azetidinone (II, Formula 1) characterized in that it is crotylation in the presence.

In the present invention, the chiral ligand is cinchonine, cinchonidin, quinine, quinine, quinidine, norephedrin, 2,2'-bis (diphenylphosphino) ) -1,1'-binafyl (BINAP), (S)-(-)-amino-3-phenyl-1-propanol {(S)-(-)-Amino-3-phenyl-1-propanol} , (R)-(-)-2-phenylglycinol {(R)-(-)-2-Phenylglycinol}, amino-2-indanol, (S)-(+) -2-amino-1-butanol {(S)-(+)-Amino-1-butanol}, O-acetylcinchonine, O-acetylcinchonidine, (R) -Bi (2-naphthol) {(R) -Bi (2-naphthol)}, (S) -bi (2-naphthol) {(S) -Bi (2-naphthol)}, S-2-aminopropanol ( S-2-Aminopropanol), R-2-aminopropanol (R-2-Aminopropanol), O-acetylquinine (O-acetylquinine), O-acetylquinidine (O-acetylquinidine) characterized in that it is selected from the group consisting of In addition, the transition metal may be characterized in that the zinc (Zn) or indium (In).

In addition, in the present invention, the Lewis acid is AgCl, PdCl, AgOTf, CuCl, CuCN, Cu (OAc) ₂ , InCl ₃ , PbBr ₂ , GaCl ₃ , Ti (OPr) _4, CeCl ₃ , Sc (OTf) _3, It is characterized in that it is selected from the group consisting of ZnCl ₂ , ZnBr ₂ , and the reaction solvent is an ether such as petroleum ether, isopropyl ether (IPE), diethyl ether, dibutyl ether, t-butyl methyl ether, dioxane ) Solvents; Tetrahydrofuran (THF), dialkoxyalkane, N, N-dimethyl foramide (DMF), dimethylacetamide, dimethylsulfonamide, dichloromethane (MC), acetonitrile (MeCN) Polar solvents such as these; It is characterized by using one or more types selected from the group consisting of aromatic solvents such as benzene and toluene alone or in parallel.

The preparation method according to the invention is not only possible to obtain the desired optical isomer in a high yield up to three times higher than conventionally, but also is an important intermediate for preparing 1β-methyl carbapenem used as an intermediate of carbapenem antibiotics. By providing an azetidinone derivative, i.e., the beta form 4- (alk-2-enyl) -2-azetidinone (Formula 1), the synthesis of an effective 1β-methyl carbapenem compound is relatively easy and at low cost. It is possible to be usefully used for industrialization.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

The present invention uses 4-acetoxyazetidinone (4 (R) -acetoxyazetidinone (I) as a starting material, and crotylation in the presence of chiral ligands, transition metals and Lewis acids. To provide 4- (alk-2-enyl) -2-azetidinone (II) represented by Chemical Formula 1 above.

Preferred embodiments of the present invention can be represented as follows.

However, in the above, R is a hydrogen atom or a hydroxyl-protecting group, particularly preferably TBDMS (t-butyldimethylsilyl group).

In the present invention, the chiral ligand is cinchonine (cinchonine), cinchonidin (cinchonidin), quinine (quinine), quinidine (quinidine), norephedrin (norephedrin), 2,2'-bis (diphenylphosphino ) -1,1'-binafyl (BINAP), (S)-(-)-amino-3-phenyl-1-propanol {(S)-(-)-Amino-3-phenyl-1-propanol} , (R)-(-)-2-phenylglycinol {(R)-(-)-2-Phenylglycinol}, amino-2-indanol, (S)-(+) -2-amino-1-butanol {(S)-(+)-Amino-1-butanol}, O-acetylcinchonine, O-acetylcinchonidine, (R) -Bi (2-naphthol) {(R) -Bi (2-naphthol)}, (S) -bi (2-naphthol) {(S) -Bi (2-naphthol)}, S-2-aminopropanol ( S-2-Aminopropanol), R-2-Aminopropanol, O-acetylquinine (O-acetylquinine), O-acetylquinidine (O-acetylquinidine) is preferably selected from the group consisting of , The transition metal is preferably zinc (Zn) or indium (In).

In addition, in the present invention, the Lewis acid is AgCl, PdCl, AgOTf, CuCl, CuCN, Cu (OAc) ₂ , InCl ₃ , PbBr ₂ , GaCl ₃ , Ti (OPr) _4, ZnCl ₂ , ZnBr ₂ , CeCl ₃ , It is preferably selected from the group consisting of Sc (OTf) ₃ .

In the present invention, the reaction solvent may be an ether solvent such as petroleum ether, isopropyl ether (IPE), diethyl ether, dibutyl ether, t-butyl methyl ether, dioxane; Tetrahydrofuran (THF), dialkoxyalkanes, N, N-dimethyl foramide (DMF), dimethylacetamide, dimethylsulfonamide, dichloromethane (MC), acetonitrile (MeCN) Polar solvents such as these; At least one selected from the group consisting of aromatic solvents such as benzene and toluene; may be used alone or in combination. Particularly, at least one selected from the group consisting of diethyl ether, THF, DMF, MC, and MeCN is preferable. .

In the present invention, the chiral ligand is preferably added in an amount of 0.005 to 3 equivalents, preferably 0.025 to 1 equivalent, and the Lewis acid is preferably added in an amount of 0.005 to 3 equivalents, preferably 0.025 to 1 equivalent, The temperature range is 0 to 50 ° C, preferably 0 to 35 ° C.

Hereinafter, the present invention will be described in more detail with reference to Examples.

However, the following examples are merely to illustrate the invention, but the content of the present invention is not limited to the following examples.

Example  4- (R)-[1- methyl ( allyl )- azetidinone Manufacture of I

In a glove box, add 0.1 g (0.34 mmol) of 4-acetoxyasetidinone (4 (R) -acetoxyasetidinone (AOSA)), 0.044 g (0.5 equiv) of cinconine, and 0.033 g (0.5 equiv) of indium chloride in a round bottom flask. Sealed with argon gas. 5 ml of ether was added thereto, and 0.081 g (2.0 equivalents) of crotyl bromide was slowly added while maintaining the reaction temperature at 25 to 35 ° C. After 30 minutes, 0.04 g (2.0 equivalents) of zinc was added, followed by a total of 4 at 29 ° C. Stirring over time, the progress of the reaction was confirmed by TLC (ether: n-hexane = 2: 1). 10 ml of saturated ammonium chloride solution and 20 ml of ether were added to the reaction mixture, stirred for 2-3 minutes, and then the water layer was removed using a separatory funnel. 2-3 g of anhydrous sodium sulfate was added to the organic layer from which the water layer was removed, followed by stirring for 15 minutes to completely remove the remaining water layer in the organic layer, followed by filtration with a glass filter, washing with an organic solvent (ether), and concentrating the organic layer under reduced pressure.

As described above, 93 mg (yield 95%) of white 4 (R)-[1-methyl (allyl) -azetidinone] having a beta-type alpha ratio of 2.5: 1 was obtained in crystalline form.

(1) beta form (β-form)

¹ H-NMR (400 MHz, CDCl ₃ ): 0.02 to 0.09 (6H), 0.83 to 0.94 (9H), 1.03 to 1.07 (3H), 1.12 to 1.18 (3H), 1.22 to 1.34 (3H), 2.25 to 2.24 ( 1H), 2.79-2.80 (1H), 3.46-3.48 (1H), 4.13-4.23 (1H), 5.02-5.13 (2H), 5.68-5.81 (1H), 6.51 (1H)

(2) alpha-form

¹ H-NMR (400 MHz, CDCl ₃ ): 0.02 to 0.09 (6H), 0.83 to 0.94 (9H), 1.03 to 1.07 (3H), 1.12 to 1.18 (3H), 1.22 to 1.34 (3H), 2.19 to 2.24 ( 1H), 2.75-2.77 (1H), 3.38-3.40 (1H), 4.13-4.23 (1H), 5.02-5.13 (2H), 5.61-5.70 (1H), 6.29 (1H)

Example 2. Preparation of 4- (R)-[1-methyl (allyl) -azetidinone] II

Prepared in the same manner as in Example 1, but was prepared by adding 2.5 ml of ether and zinc at the same time, the beta form of the alpha form ratio of 2.0: 1 4 (R)-[1-methyl (allyl)- azetidinone] was obtained in crystalline form (yield 95%).

Examples 3 to 26. Preparation of 4- (R)-[1-methyl (allyl) -azetidinone] III.

Using 0.3 mmol of ASOA as a starting material, the preparation was carried out in the same manner as in Example 2, and the chiral ligand, Lewis acid, transition metal, and solvent used were shown in Table 1 below with the obtained ratios.

Example Chiral ligand Equivalent (eq.) Lewis Mountain Equivalent (eq.) menstruum Transition metal Ratio (β: α) 3 cinchonine 0.5 InCl ₃ 0.1 Ether Zn 2.1: 1.0 4 cinchonine One AgCl 0.1 THF Zn 2.0: 1.0 5 cinchonidine 0.5 InCl ₃ 0.5 Ether Zn 1.6: 1.0 6 cinchonine 0.5 AgOTf 0.5 THF In 1.78: 1.0 7 cinchonine 0.5 InCl ₃ 0.5 DMF Zn 1.4: 1.0 8 cinchonine One InCl ₃ One Ether Zn 1.7: 1.0 9 cinchonine 0.5 InCl ₃ 0.5 DMF Zn 1.2: 1.0 10 cinchonidine 0.5 InCl ₃ 0.5 DMF Zn 1.2: 1.0 11 cinchonine 0.5 InCl ₃ One Ether Zn 1.5: 1.0 12 Quinidine 0.5 InCl ₃ 0.5 Ether Zn 1.8: 1.0 13 (S)-(-)-Amino-3-phenyl-1-propanol 0.5 Ti (OPr) ₄ 0.5 Ether Zn 1.4: 1.0 14 Amino-2-indanol 0.5 Ti (OPr) ₄ 0.5 Ether Zn 1.25: 1.0 15 cinchonine 0.1 InCl ₃ 0.1 Ether Zn 2.5: 1.0 16 cinchonidine 0.1 InCl ₃ 0.1 Ether Zn 2.5: 1.0 17 Quinine 0.1 InCl ₃ 0.1 Ether Zn 2.4: 1.0 18 Quinidine 0.1 InCl ₃ 0.1 Ether Zn 2.6: 1.0 19 cinchonine 0.2 InCl ₃ 0.1 Ether Zn 2.5: 1.0 20 cinchonidine 0.2 InCl ₃ 0.1 Ether Zn 2.4: 1.0 21 Quinine 0.2 InCl ₃ 0.1 Ether Zn 2.5: 1.0 22 Quinidine 0.2 InCl ₃ 0.1 Ether Zn 2.6: 1.0 23 cinchonine 0.05 InCl ₃ 0.05 Ether Zn 2.8: 1.0 24 cinchonidine 0.05 InCl ₃ 0.05 Ether Zn 2.8: 1.0 25 Quinine 0.05 InCl ₃ 0.05 Ether Zn 2.8: 1.0 26 Quinidine 0.05 InCl ₃ 0.05 Ether Zn 2.6: 1.0

Example 27 Preparation of 4- (R)-[1-methyl (allyl) -azetidinone] IV

In a round bottom flask, 4-acetoxyazetidinone (4- (R) -acetoxyasetidinone (AOSA) 200 mg (0.69 mmol), quinine 5.6 mg (2.5 mol%), indium chloride 3.8 mg (2.5) mol%) was added and sealed with argon gas. To this was added 5 ml of ether, slowly adding 0.143 ml of crotyl bromine while maintaining the reaction temperature at 25 to 35 ° C., and after 30 minutes, 90.8 mg of zinc was added and stirred at 29 ° C. for a total of 6 hours. It was confirmed that (ether: n-hexane = 2: 1).

To the reaction was added 20 ml of saturated ammonium chloride solution and 20 ml of ether and stirred for 2 to 3 minutes, and then the water layer was removed using a separatory funnel. Anhydrous sodium sulphate was added to the organic layer from which the water layer was removed and stirred for 15 minutes to completely remove the water layer remaining in the organic layer, filtered through a glass filter, washed with an organic solvent ether, and concentrated under reduced pressure.

In the same manner as above, white 4 (R)-[1-methyl (allyl) -azetidinone] having a beta-alpha ratio of 3: 1 was obtained in crystalline form (yield 95%).

Example 28 Preparation of 4- (R)-[1-methyl (allyl) -azetidinone] V

Prepared in the same manner as in Example 27, except that 10 ml of ether and zinc were added at the same time, and the beta-alpha-form ratio was 3: 1 in white 4 (R)-[1-methyl (allyl)-. azetidinone] was obtained in crystalline form (yield 95%).

Examples 29-36 Preparation of 4- (R)-[1-methyl (allyl) -azetidinone] VI

Using 0.69 mmol of ASOA as a starting material, the reaction was carried out in the same manner as in Example 27, whereby the title compound was prepared as shown in Table 2 below.

Example Chiral ligand Equivalent (eq.) Lewis Mountain Equivalent (eq.) menstruum Transition metal Reaction temperature (℃) Ratio (β: α) 29 cinchonine 0.025 InCl ₃ 0.025 Ether Zn 25-30 2.2: 1 30 cinchonidine 0.025 InCl ₃ 0.025 Ether Zn 25-30 3.0: 1 31 quinine 0.025 InCl ₃ 0.025 Ether Zn 25-30 3.0: 1 32 quinidine 0.025 InCl ₃ 0.025 Ether Zn 25-30 3.0: 1 33 cinchonidine 0.05 InCl ₃ 0.05 Ether Zn 25-30 2.2: 1 34 cinchonine 0.0125 InCl ₃ 0.0125 Ether Zn 25-30 2.7: 1 35 quinidine 0.0125 InCl ₃ 0.0125 Ether Zn 25-30 2.5: 1 36 quinine 0.025 InCl ₃ 0.025 Ether Zn 0-5 1.7: 1

Example  37. 4- (R)-[1- methyl ( allyl )- azetidinone Manufacturing of Ⅶ

In a round bottom flask in a glove box, 1.44 g (5.0 mmol) of (3R, 4R) -4-acetoxy-3-{(R) -l '[(t-butyldimethylsilyl) oxy] ethyl} -2-azetidinone, cinconidine (cinchonidine) 0.029 g (2.0 mol%) and indium chloride 0.022 g (2.0 mol%) were added and sealed with argon gas. 42 ml of ether was added thereto, and 1.0 ml (2.0 equivalents) of crotyl bromide was slowly added while maintaining the reaction temperature at 25 to 30 ° C. After 30 minutes, 0.65 g (2.0 equivalents) of zinc was added thereto for a total of 4 hours at 29 ° C. Stirring over, the progress of the reaction was confirmed by TLC (ether: n-hexane = 2: 1). The reaction was washed twice with 10 ml of saturated ammonium chloride solution and 20 ml of ether. After washing, the organic layer was concentrated under reduced pressure by removing water with Na ₂ SO ₄ . In the same manner as above, a white product having a ratio of beta form to alpha form of 3.2: 1 was obtained in the same yield (yield 95%).

Claims (7)

 4-acetoxy azetidinone (4 (R) -acetoxyazetidinone) as a starting material, and crotylation (crotylation) in the presence of chiral ligand (Chiral Ligand), transition metal, Lewis acid (Formula 1 below) Method for preparing 4- (alk-2-enyl) -2-azetidinone represented by. [Formula 1] With the proviso that R ₁ and R ₂ Are each H, Me and R ₃ is a hydrogen atom or a hydroxyl-protecting group. The method of claim 1, The chiral ligands are cinchonine, cinchonidin, quinine, quinidine, norephedrin, 2,2'-bis (diphenylphosphino) -1,1 '-Binafyl (BINAP), (S)-(-)-amino-3-phenyl-1-propanol {(S)-(-)-Amino-3-phenyl-1-propanol}, (R)- (-)-2-phenylglycinol {(R)-(-)-2-Phenylglycinol}, amino-2-indanol, (S)-(+)-2-amino- 1-butanol {(S)-(+)-Amino-1-butanol {, O-acetylcinchonine, O-acetylcinchonidine, (R) -bi (2- Naphthol) {(R) -Bi (2-naphthol)}, (S) -bi (2-naphthol) {(S) -Bi (2-naphthol)}, S-2-aminopropanol ), R-2-aminopropanol (R-2-Aminopropanol), O-acetylquinine (O-acetylquinine), O-acetylquinidine (O-acetylquinidine) The production method characterized in that it is selected from the group consisting of. The method of claim 1, wherein the transition metal is zinc (Zn) or indium (In). The method of claim 1, The Lewis acid is composed of AgCl, PdCl, AgOTf, CuCl, CuCN, Cu (OAc) ₂ , InCl ₃ , PbBr ₂ , GeCl ₃ , Ti (OPr) _4, ZnCl ₂ , ZnBr _2, CeCl ₃ , Sc (OTf) ₃ Manufacturing method characterized in that selected from the group. The method of claim 1, The crotylation reaction solvent is an ether solvent consisting of petroleum ether, isopropyl ether (IPE), diethyl ether, dibutyl ether, t-butylmethyl ether, dioxane; Tetrahydrofuran (THF), dialkoxyalkane, N, N-dimethyl foramide (DMF), dimethylacetamide, dimethylsulfonamide, dichloromethane (MC), acetonitrile (MeCN) A polar solvent consisting of; Aromatic solvents consisting of benzene and toluene; A production method characterized by using one or more selected from alone or in parallel. The method of claim 1, The reaction is characterized in that the proceeding in the temperature range of 0 ~ 50 ℃. The method of claim 1, The Lewis acid is characterized in that the addition method in the range of 0.005 ~ 3 equivalents.