ethyl 5-benzyloxy-2-{(2-(dimethylsulfonium)ethoxy)methyl}-6-oxo-1,6-dihydropyrimidine-4-carboxylate iodide 在
potassium carbonate 作用下,
以
DMF (N,N-dimethyl-formamide) 为溶剂,
反应 48.0h,
以72%的产率得到ethyl 3-benzyloxy-4-oxo-4,6,7,9-tetrahydropyrimido[2,1-c][1,4]oxazine-2-carboxylate