Acetic Acid → HCID 53724661, Verbindung

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A suspension of 8-chloro-7-fluoro-1-methyl-4-oxo-1,4-dihydrobenzo[b][1,8]naphthyridine-3-carboxylic acid (1.6 g) and (RS)-2-(4-fluorophenyl)piperazine (3.7 g) in pyridine (16 cc) is heated to a temperature in the region of 115° C. for 24 hours. The reaction mixture is concentrated under reduced pressure (20 kPa) at approximately 60° C. The residue is taken up with ethanol (40 cc) and concentrated again under reduced pressure under the above conditions. The solid obtained is taken up with water (10 cc), treated with 10% strength acetic acid (1.75 cc), drained and washed with water (2×10 cc) and ethanol (2×10 cc). After 2 recrystallizations in dimethylformamide (10 cc each time), (RS)-7-fluoro-8-[3-(4-fluorophenyl)-1-piperazinyl]-1-methyl-4-oxo-1,4-dihydrobenzo[b ][1,8]naphthyridine-3-carboxylic acid (1.1 g) is obtained in the form of a yellow solid, m.p. 270°-275° C.

Herkunft & Nachweise