76981-73-2 BRN 5565004 Benzo(b)thiophene-3-carboxylic acid, 4,5,6,7-tetrahydro-2-(acetylamino)-6-methyl-, ethyl ester Ethyl 4,5,6,7-tetrahydro-2-(acetylamino)-6-methylbenzo(b)thiophene-3-carboxylate