ethyl 1--7-(4-tert-butoxycarbonyl-1-piperazinyl)-6,8-difluoro-1,4-dihydro-4-oxoquinoline-3-carboxylate 在
caesium carbonate 作用下,
以
二甲基亚砜 为溶剂,
反应 10.0h,
以80%的产率得到ethyl 3-(diphenylmethoxycarbonyl)-5-fluoro-2,3-dihydro-4-(4-tert-butoxycarbonyl-1-piperazinyl)-1-methyl-2,7-dioxo-1H,7H-pyrido<3,2,1-i,j>cinnoline-8-carboxylate