Abstract The attempted cyclization of S-(3, 4-dimethoxyphenyl)-N-(hydroxymethyl) thioglycolamide (6) with phosphoryl chloride gave, instead of the expected benzothiazepinone 7e,(3, 4-dimethoxyphenylthio) acetonitrile (8). The product of ring closure of N-[[2-(benzoylthio)-4, 5-dimethoxyphenyl] methyl]-2-chloroacetamide (11) with sodium ethoxide was 4, 5-dihydro-7, 8-dimethoxy-1, 4-benzothiazepin-3 (2H)-one (7e). ...