- AN IMPROVED PROCESS FOR THE PREPARATION OF MEROPENEM
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The present invention provides an improved process for the preparation of methyl carbapenem derivative of formula (I) or its pharmaceutically acceptable salts or hydrates thereof in a pure form.
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Page/Page column 10-12
(2011/12/02)
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- A PROCESS FOR THE PREPARATION OF THE INTERMEDIATE OF Β-METHYL CARBAPENEM
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A process of preparation of the intermediate of β-methyl carbapenem is disclosed, in which 4-acetylazacyclobutanone as the raw material is firstly reacted with α-bromopropionamide having a big inductive group. Since this reaction is highly stereoselectivity, most of the product is the required parent nucleus of β-methyl carbapenem, a product of β-configuration. Compared with the prior art, the process of the present invention is highly-yielding, cost-effective and can be used for large scale production.
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Page/Page column 13-14
(2010/11/28)
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- A PROCESS FOR THE PREPARATION OF MEROPENEM
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The invention relates to a process for the preparation of meropenem, a β-methylcarbopenem. The said process comprises the following steps: preparing the compound of Formula (XI) from the compound of Formula (IV) through three steps "one-pot process"; then condensing the compound of Formula (XI) with the compound of Formula (XX) to form the compound of Formula (XXIV); finally preparing meropenam of Formula (I) from the compound of Formula (XXIV) by deprotection reaction by means of catalyst. The process of the invention is easily to carry out, the product is isolated in high content and yield, and the cost is reduced, thereby overcoming the shortage of the prior art.
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Page/Page column 15-16
(2010/11/28)
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- β-Lactams. 3. Asymmetric Total Syntheis of New Non-Natural 1β-Methylcarbapenems Exhibiting Strong Antimicrobial Activities and Stability against Human Renal Dehydropeptidase-I
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Asymmetric synthesis of 11, the precursor to chiral (3R,4R)-3-ethyl>-4-acetoxyazetidin-2-one (3) was achieved by utilizing a highly diastereoselective aldol-type reaction of acetaldehyde and the chiral tin(II) enolate of 5.Similar diastereoselective alkylations of chiral and achiral tin(II) enolates 13a-d with chiral 3 were also performed to obtain the desired alkylated azetidin-2-ones (17a-d).Compounds 17a,b were successfully converted to new, non-natural 1β-methylcarbapenems 1a and 1b, which exhibited strong and wide-ranging antimicrobial activities and excellent stability against human renal dehydropeptidase-I.
- Nagao, Yoshimitsu,Nagase, Yunosuke,Kumagai, Toshio,Matsunaga, Hiroshi,Abe, Takao,et al.
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p. 4243 - 4249
(2007/10/02)
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- 3,4-disubstituted-2-azetidinone derivatives and processes for preparation using tin enolates
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The invention relates to the preparation of 3,4-disubstituted-2-azetidinone compounds of the formula: STR1 in which R1 is hydrogen or amido-protective group, R2 is hydroxy(lower)alkyl or protected hydroxy(lower)alkyl, R3 is lower alkyl, and R4 is 1-(lower)alkyl-1-hydroxy(C2 -C6)alkyl, 1-(lower)alkyl-1-(protected hydroxy)-(C2 -C6)alkyl or 2-thioxothiazolidin-3-yl, useful as an intermediate for the production of antimicrobial agents by reacting a compound a compound of the formula: STR2 in which R5 is acyl, or salts thereof, with a compound of the formula: or salts thereof, in the presence of an enolizating agent selected from the group consisting of stannous(lower)alkylsulfonate and stannous perhalo(lower)alkylsulfonate.
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- SYNTHESIS OF 1-β-METHYLCARBAPENEM KEY INTERMEDIATES INVOLVING THE LABILE ACYL AUXILIARY 4,4-DIMETHYL-1,3-OXAZOLIDINE-2-THIONE
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A convenient synthesis of 1-β-methylcarbapenem key intermediates based on the facile displacement of the 4,4-dimethyl-1,3-oxazolidine-2-thione auxiliary of 5 is described.
- Deziel, Robert,Favreau, Denis
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p. 1345 - 1348
(2007/10/02)
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- SYNTHETIC CARBAPENEM ANTIBIOTICS I. 1-&β-METHYLCARBAPENEM
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A total synthesis of a novel 1-β-methylcarbapenem antibiotic, (-)-(1R,5S,6S)-2-(2-N,N-dimethylamino-2-iminoethylthio)-6--1-methylcarbapen-2-em-3-carboxylic acid 1, is reported.Compound 1 is highly resistant to renal dipeptidase-I yet retains the excellent antibacterial activities of N-formimidoylthienamycin.
- Shih, David H.,Baker, Florence,Cama, Lovji,Christensen, Burton G.
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