Patent ID: 6013829
Filing Date: 2000-01-11
Classification: C07C

Abstract:
A process for the preparation of an S-acyl of the formula ##STR28## wherein R.sub.1 is an acyl of an aliphatic carboxylic acid or an aromatic carboxylic acid and Ph is phenyl comprising(a) reducing a malonic acid ester of the formula ##STR29## wherein R.sub.4 is alkyl of 1 to 4 carbon atoms in the presence of a hydride to obtain a diol of the formula ##STR30## b) reacting the compound of Formula VI with an acetylating agent to obtain the monoacetates of the formula ##STR31## c) oxidizing the monoacetates of formula (VIIR) or (VIIS) to form the acids of the formulae ##STR32## d) saponifying the compounds of formula IXS and IXR in the presence of a basic aqueous solution to form the hydroxy acids of the formulae ##STR33## e) thioacylating the said hydroxy XS and XR acids with a mercapto acid of the formulaR.sub.1 SH XIwherein R.sub.1 is aliphatic acyl or an aromatic acyl as defined above, according to a reaction of Mitsunobu type in the presence of an alkyl azodicarboxylate/triphenylphosphine complex to obtain the desired acids of the formulae ##STR34##