HCID 15751522, compound → HCID 19101719, compound

Participants

Reaction Steps

tert-Butyl 7-[4-(tert-butoxycarbonyl)-1-piperazinyl]-5-cyclopropyl-8-fluoro-3,5-dihydro-1,3-dioxopyrimido-[1,6-a]benzimidazol-2(1H)-carbamate (0.145 g, 0.26 mmol) is dissolved in 1 ml of trifluoroacetic acid and stirred at room temperature for 2 hours. The reaction solution is concentrated, treated with 1 ml of H2O, adjusted to pH 8 with saturated aqueous NaHCO3 solution and stirred at room temperature for 1 hour. The suspension is cooled to 0° and suction filtered. The product is chromatographed on silica gel (eluent: CHCl3 /EtOH/NH4OH 80:20:1) and recrystallized from ethanol. There is obtained 2-amino-5-cyclopropyl-8-fluoro-7-(1-piperazinyl)pyrimido[1,6-a]benzimidazole-1,3(2H,5H)-dione. Yield: 43 mg (46%); m.p. 232°-234°.

Provenance & Evidence