2-(1-butyl-2-oxopyridin-4-yl)acetic acid

1,5-diphenyltriazole-4-carboxylic acid

3-butyl-5-oxo-2H-oxadiazol-3-ium-4-carboxylate

5-溴-3-叔丁氧基羰基氨基-噻吩-2-羧酸

5-氯-2-苯并噁唑羧酸