Phosgene → HCID 20242853, compound

Participants

Reaction Steps

A mixture of 7-chloro-6-sulfamoylisatoic anhydride (7.45 g) and 1-(2-aminoethyl)-4-(2-methoxyphenyl)piperazine (6.64 g) was dissolved in methanol (100 ml), and the resulting mixture was heated under reflux for 3 hours under a nitrogen stream. After completion of the reaction, the solvent was distilled off under vacuum and the residue was recrystallized from methanol-acetone and dried to give 2-amino-4-chloro-5-sulfamoyl-N-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]benzamide. A solution of this benzamide derivative (1.32 g) in acetic acid (20 ml) was added dropwise to a solution of phosgene (2.33 g) in toluene (10 ml) under stirring at room temperature. Then, the mixture was refluxed for one hour and cooled to room temperature. The resulting crystal was filtered and suspended in a mixture of methanol (10 ml) and water (10 ml), and after passing hydrogen chloride gas into the suspension for about 5 minutes, the solvent was distilled off under vacuum to provide a crystalline residue. It was recrystallized from water-methanol-ether to give colorless needles crystal of 7-chloro-6-sulfamoyl-3-[2-[4-(2-methoxyphenyl)-1-piperazinyl]ethyl]-2,4-(1H,3H)quinazolinedione hydrochloride (200 mg) having a m.p. of 266°-268° C. (with decomposition).

Provenance & Evidence