2-carboxy-5-(ethoxycarbonyl)-4-methyl-1H-pyrrole-3-propionic acid ethyl ester

2-carboxy-5-ethoxycarbonyl-4-methylpyrrole-3-propionic acid

(E)-3-(5-ethoxycarbonyl-2,4-dimethyl-1H-pyrrol-3-yl)prop-2-enoic acid

4-(2-羧基-乙基)-3,5-二甲基-1H-吡咯-2-羧酸乙酯

3-(4-carboxymethyl-pyrrol-3-yl)-propionic acid