1. Urea, polymer with ammonium chloride , cyanoguanidine and formaldehyde;
   名称 脲与氯化铵;氰基胍和甲醛的聚合物;
2. Cyanoguanidine and acetylated β-D-ribose were used as starting materials to give target compound via salt formation, cyclization, silylation, coupling reaction and deprotection.
   摘要以氰基胍和甲酸为原料，经成盐、环合反应得到5-氮杂胞嘧啶，5-氮杂胞嘧啶经硅烷化保护后，与乙酰化的核糖成苷，再脱保护基得到氮杂胞苷。

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