PURPOSE: To prepare the titled compound useful as a remedy for cardiopathy, by the condensation cyclization of 2-hydroxy-3-(p-methoxyphenyl)-3-(o-halogenophenylthio)propionic acid amide derivative in the presence of copper powder or a copper compound and a base.

CONSTITUTION: The objective compound of formula II can be prepared by the condensation cyclization of the compound of formulaI(X is halogen; R1 is H or acetyl; R2 is H or β-dimethylaminoethyl) in a solvent such as DMF, N-ethyl- 2-pyrrolidone, etc. in the presence of copper powder or a copper compound (e.g. copper oxide, copper carbonate, copper acetate, copper EDTA complex, etc.) and a base under heating. The compound of formulaIis also a novel compound, and can be prepared by (1) reacting the o-halogenothiophenol with p- methoxyphenyl glycide ester of formula III, (2) hydrolyzing the product in a dilute aqueous solution of alkali to obtain the compound of formula IV, and (3) amidating the compound as it is or after acetylation.