Patent ID: 6818788
Filing Date: 2004-11-16
Classification: A61P,C07C,C07D

Abstract:
A process for the synthesis of the compounds of formula (I) wherein R represents linear or branched (C1-C6)alkyl, wherein sodium pyruvate of formula (III): is condensed with a compound of formula (IV): wherein R is as defined for formula (I), with hydrogenation catalysed by 5% palladium-on-carbon, in water, at a pressure of 1 to 20 bar, at a temperature of 10 to 60Â° C., in the presence of sodium hydroxide in an amount of 0.1 to 0.2 mol per mol of compound of formula (IV) used, to yield the compound of formula (I) directly, in optically pure form, following acidification of the reaction mixture to a pH of 2.8 to 4.5 and then filtration.