反应详情

The reaction is performed under the conditions of Example 4, but starting with 8-chloro-1-ethyl-7-fluoro-4-oxo-1,4-dihydrobenzo[b][1,8 ]-naphthyridine-3-carboxylic acid (1.5 g) and (RS)-2-(4-fluorophenyl)piperazine (3.4 g) in pyridine (15 cc). (RS)-1-Ethyl-7-fluoro-4-oxo-8-[3-(4-fluorophenyl)-1-piperazinyl]-1,4-dihydrobenzo[b][1,8]naphthyridine-3-carboxylic acid (0.92 g) is obtained in the form of a yellow solid, m.p. 298° C.