4-(3-甲氧基-3-氧代丙基)-3,5-二甲基-1H-吡咯-2-羧酸乙酯

2,4-二甲基-5-乙氧羰基-3-吡咯丙酸乙酯

4-(2-carboxy-ethyl)-3-carboxymethyl-5-methyl-pyrrole-2-carboxylic acid

3-(2,4-二甲基-5-羧基-1H-3-吡咯)丙酸

胆红素