3-(4-methoxybenzoyl)-5H-pyrrolo[1,2-a]quinoxaline-1,2,4-trione

2-氯-2-氧代乙酸叔丁酯

acetyl isocyanate

2-(4-oxo-3,1-benzoxazin-2-yl)-3,1-benzoxazin-4-one

1-异丙基咪唑啉-2,4,5-三酮