Thienyl- and furyl-acetic acids and esters prepn - from 1-sulphinyl-1-mercapto-2-(furyl or thienyl)-ethylene derivs and water or alkanol with a mineral acid catalyst

摘要

Cpds. of formula (I) (where Y is -CH2COOR2; X is S or O; R1 and R2 are each H or alkyl) are prepd. by reacting, in the presence of a mineral acid catalyst, a cpd. of formula (I: Y is -CH=C(SR)-S-(=O)-R) (where R is (substd.) alkyl or Ph), with an alcohol of formula R2OH. The process does not require strict control, does not use toxic reagents and gives good yields. The prods. are inters., e.g. agents for modification of penicillin and cephalosporin antibiotics.