8-Fluorociprofloxacin → PD 135042

Participants

Reaction Steps

To the solution of sodium methoxide prepared from sodium (0.2 g) and absolute ethanol (9 ml) was added 1-cyclopropyl-6,8-difluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)-3-quinolinecarboxylic acid (0.5 g) and the mixture in sealed tube was heated for 72.5 hours at 140° to 150° C. After cooling, the reaction mixture was concentrated, water (4 ml) was added to the residue, and the solution was adjusted to pH 7 with acetic acid. The insoluble materials were filtered off and the filtrate was allowed to stand in a refrigerator. The resulting precipitate was collected by filtration and recrystallized from dichloromethane-methanol (2:1; 6 ml) to give the title compound (0.12 g) as colorless prisms, mp 185°-187.5° C. (decompd.).

Provenance & Evidence