25991-27-9
2-氧代-2H-吡喃-3-甲酸甲酯
→
~78%
3040-20-8
2-oxopyran-3-carboxylic acid
19978-32-6
3-溴-2H-吡喃-2-酮
18398-80-6
2-氧代-2H-吡喃-3-羰酰氯