5-bromo-(2,2'-bithiophen)-5'-carboxylic acid methyl ester

5,5'-二溴-2,2'-联噻吩

methyl 2-chloromethyl-5-thiophenecarboxylate

甲基 4,5-双(氯甲基)噻吩-2-羧酸

Methyl 4-(chloromethyl)thiophene-2-carboxylate