3357-55-9
ethyl 5-ethoxy-2-methyl-1,3-oxazole-4-carboxylate
→
3357-62-8
5-ethoxy-2-methyl-1,3-oxazole-4-carbonyl chloride
3357-56-0
5-乙氧基-2-甲基噁唑-4-羧酸