N4-Benzoylcytosine

• 3′-C-ethynyl and 3′-C-(1,4-disubstituted-1,2,3-triazolo) double-headed pyranonucleosides
• 2′-C-methyl-4′-thiocytidine, via the Pummerer reaction
• 2′-fluorinated L-nucleoside analogs

71-30-7

98-88-4

26661-13-2

Under nitrogen protection, 100 L of acetonitrile was added to the reactor as a solvent, followed by 22 kg (196 mol) of 6-aminopyrimidin-2(1H)-one (anhydrous cytosine), 25 g of 4-dimethylaminopyridine (DMAP), and 24 kg of triethylamine as a base. After cooling the reaction mixture to 5-8°C, 34 kg of benzoyl chloride was slowly added dropwise. After the dropwise addition, the reaction mixture was allowed to warm up naturally to room temperature and stirred at 25°C for 1 hour. Subsequently, the reaction mixture was slowly heated to 40-45°C and kept at this temperature for 2 hours. Upon completion of the reaction, it was cooled to room temperature and press-filtered. About 60 L of acetonitrile filtrate was collected for recycling, and the filter cake was washed sequentially with water and ethanol, and dried to give 40 kg of a white solid product, N4-benzoylcytosine, which was analyzed by liquid chromatography to be 99.2% pure.