[(2R,5S)-(5-氟胞嘧啶-1-基)-1,3-氧硫环戊烷-2-羧酸?基酯(6)经硼氢化钠还原后,用盐酸除去剩余硼氢化钠,蒸除大部分乙醇,甲苯洗涤除去副产物薄荷醇,加入苯甲酸反应2 h,过滤得苯甲酸恩曲他滨,与三乙胺及乙酸乙酯混合,15~30℃搅拌反应4 h,抽滤,即可得到高纯度的抗病毒药恩曲他滨,总收率72.2%(以6计)。 [(2R, 5S) - (5-fluorocytosin-1-yl) -1,3-oxathiolane-2-carboxylate (6) After reduction with sodium borohydride, the remaining Sodium borohydride, most of the ethanol was distilled off, the by-product menthol was removed by washing with toluene, benzoic acid was added to react for 2 h, and then the erlotimine benzoate was filtered, mixed with triethylamine and ethyl acetate, and stirred at 15-30 ° C. 4 h, suction filtration, you can get a high-purity antiviral ermontamycin, the total yield of 72.2% (6).