反应详情

Working under the conditions of Example 39, but starting with 3-ethoxycarbonyl-7,8,9-trifluoro-1-methyl-4-oxo-1,4-dihydrobenzo[b][1,8]naphthyridine (1.21 g) and (R)-2-phenylpiperazine (0.7 g), and after recrystallization in ethanol (22 cc) containing dimethylformamide (30%), (R)-3-ethoxycarbonyl-7,9-difluoro-1-methyl-4-oxo-8-(3-phenyl-1-piperazinyl)-1,4-dihydrobenzo[b][1,8]naphthyridine (1.02 g) is obtained in the form of a yellow solid, m.p. 216° C.

1. customafter recrystallization in ethanol (22 cc)
2. additioncontaining dimethylformamide (30%)