181289-34-9Relevant articles and documents
Development of a new synthesis approach for S-pregabalin by optimizing the preparation stages
Mansoori, Arsalan,Zahednezhad, Fahimeh,Bavili Tabrizi, Ahad,Shahbazi Mojarrad, Javid
, p. 89 - 101 (2019/09/13)
In the present study, we aimed to optimize the synthesis stages of S-pregabalin ((S)-3-(aminomethyl)-5-methylhexanoic acid), a well-known anticonvulsant drug. We used appropriate solvents and compounds to reach a straightforward and applicable method. The advantages of this research were avoiding use of expensive and environment pollutant reagents and solvents, and also using a recoverable reagent. Discarding prevention of the intermediates and reagents besides attaining a higher yield of the obtained product were the additional achievements. All structures were characterized by FT-IR, 1H NMR, and the purity of S-pregabalin was evaluated using the HPLC assay.
KINETIC RESOLUTION
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Page/Page column 34, (2011/06/26)
Whilst methodologies for the Kinetic Resolution of alcohols are well established, no analogous direct methods exist for the highly selective, direct catalytic Kinetic Resolution of thiols (i.e., R-SH). The present invention relates to a method for resolving stereoisomeric mixtures of thiols. In particular, the present invention relates to purely organocatalytic mediated resolution of enantiomeric mixtures of thiols without the need for enzymes. Also disclosed are some novel catalysts. Such catalysts may comprise a cinchona alkaloid-derived moiety.
Synergistic organocatalysis in the kinetic resolution of secondary thiols with concomitant desymmetrization of an anhydride
Peschiulli, Aldo,Procuranti, Barbara,O'Connor, Cornelius J.,Connon, Stephen J.
scheme or table, p. 380 - 384 (2010/09/04)
Kinetic resolution is an important method for the separation of racemates into their component enantiomers. Thiols are precursors to a variety of organosulfur compounds, with high utility in both chemistry and chemical biology, yet there is a surprising dearth of methodologies for their direct and efficient catalytic kinetic resolution. Here, we demonstrate an organocatalytic process involving the highly enantioselective desymmetrization of an achiral electrophile with the simultaneous kinetic resolution of a racemic thiol. The preparative potential of the methodology is exemplified by the synthesis of a drug precursor antipode in excellent yield and enantioselectivity as a by-product of a process that also resolves a sec-thiol substrate with a selectivity of S = 226 (that is, both thiol antipodes produced in 95% ee at 51% conversion). In a second example a racemic sec-thiol representing the stereocentre-containing core of the anti-asthma drug (R)-Montelukast was resolved with synthetically useful selectivity under mild conditions.
STEREOSELECTIVE ENZYMATIC SYNTHESIS OF (S) OR (R)-ISO-BUTYL-GLUTARIC ESTER
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Page/Page column 16-17, (2010/01/30)
The present invention relates to a stereoselective enzymatic synthesis of (S) or (R)-iso-butyl-glutaric ester, an intermediate of S-Pregabalin.
An efficient process of racemization of 3-(Carbamoylmethyl)-5- methylhexanoic acid: A pregabalin intermediate
Chavan, Anil B.,Maikap, Golak C.,Gurjar, Mukund K.
scheme or table, p. 812 - 814 (2010/04/22)
A simple and cost-effective process for racemization of undesired (S)-3-(carbamoylmethyl)-5-methylhexanoic acid (9), produced during the resolution step, is described. The literature procedure is fraught with many difficulties including number of steps and hazardous reagents. We have developed a one pot process for the above-mentioned racemization of S-enantiomer. The basic objective is to convert S-enantiomer into the symmetrical glutarimide derivative followed by hydrolysis with an alkali. The transformation of 9 into glutarimide derivative (10) has been achieved with piperidine in refluxing toluene.
