2-(Furan-2-yl)piperazine → (RS)-3-Ethoxycarbonyl-7,9-difluoro-8-[3-(2-furyl)-1-piperazinyl]-1-methyl-4-oxo-1,4-dihydrobenzo[b][1,8]naphthyridine

Participants

Reaction Steps

(RS)-3-Ethoxycarbonyl-7,9-difluoro-8-[3-(2-furyl)-1-piperazinyl]-1-methyl-4-oxo-1,4-dihydrobenzo[b][1,8]naphthyridine was prepared 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 (1.85 g) and (RS)-2-(2-furyl)piperazine (1 g). After concentration of the combined organic extracts under reduced pressure (20 kPa, approximately 40° C.), the residual solid is recrystallized in ethanol (100 cc). (RS)-3-Ethoxycarbonyl-7,9-difluoro-8-[3-(2-furyl)-1-piperazinyl]-1-methyl-4-oxo-1,4-dihydrobenzo[b][1,8]naphthyridine (1.72 g) is obtained in the form of a yellow solid, m.p. 208°-210° C.

Provenance & Evidence