Piperazine → 1-Cyclopropyl-3-ethoxycarbonyl-7,9-difluoro-4-oxo-8-(1-piperazinyl)-1,4-dihydro-benzo[b][1,8]naphthyridine

Participants

Reaction Steps

The 1-cyclopropyl-3-ethoxycarbonyl-7,9-difluoro-4-oxo-8-(1-piperazinyl)-1,4-dihydro-benzo[b][1,8]naphthyridine was prepared under the conditions of Example 35 but starting from 1.5 g of 1-cyclopropyl-3-ethoxycarbonyl-7,8,9-trifluoro-4-oxo-1,4-dihydrobenzo[b][1,8]naphthyridine and 2.7 g of piperazine. After recrystallizing once from 40 cm3 of propan-2-ol, 1 g of 1-cyclopropyl-3-ethoxycarbonyl-7,9-difluoro-4-oxo-8-(1-piperazinyl)-1,4-dihydro-benzo[b][1,8]naphthyridine is obtained in the form of a yellow solid melting at 256° C.

Provenance & Evidence