1-(4-甲基苯基)-1H-吡咯-2,5-二酮

4-amino-2-(ethylamino)-4-oxobutanoic acid

2-(3-oxo-4H-1,4-benzothiazin-2-yl)acetamide

3-(carboxyamino)prop-2-enoic acid

4-amino-2-(benzylamino)-4-oxobutanoic acid