A process for the preparation of heterocyclic carboxylic acids or salts thereof with inorganic or organic bases.

摘要

Benzofuran and benzothiophene derivs. Title compds. (I) useful as diuretics and saluretics, (where X is O or S, Y is H or Me, Z1 is Cl, Br, I, Me or MeO, Z2 is H or Me and R is 1-5C alkyl) are prepd. by reacting the corresponding 5-formyl deriv. or a functional deriv. e.g. an imine, with a compd. RCN2NO2 or by hydrolysis of an ester of (I).