4-chloro-2-methylthiophene-3-carboxylic acid
ethyl 4-chloro-2-methylthiophene-3-carboxylate
3-chloro-4-(ethoxycarbonyl)-5-methylthiophene-2-carboxylic acid
ethyl 4-chloro-5-formyl-2-methylthiophene-3-carboxylate
4-hydroxy-2-methyl-thiophene-3-carboxylic acid ethyl ester