Citric Acid → 7-Nitro-1H-1,2,4-thiadiazolo[3,4-b]quinazolin-5-one-2,2-dioxide

Beteiligte Stoffe

Reaktionsschritte

To a stirred solution of 5-nitroisatoic anhydride (1.04 g, 5.0 mmol) and S-methyl-N-(chloromethanesulfonyl)isothiourea (1.04 g, 5.0 mmol) in acetonitrile (10 ml) under nitrogen is added 4-(N,N-dimethylamino)-pyridine (0.61 g, 5.0 mmol). The solution is refluxed for 16 hr, cooled, and poured into 10% aqueous citric acid. The resulting solid is collected by filtration and recrystallized twice from isopropanol/DMF, then from DMSO, to provide the title compound as a light yellow solid, mp >300° C. (225 mg, 16%).

Herkunft & Nachweise