A protected 2'-deoxycytidine is purified by precipitating the protected 2'-deoxycytidine represented by general formula (3) in the form of a hydrated crystal from a solution containing the protected 2'-deoxycytidine and water, and by recovering the protected 2'-deoxycytidine:
wherein R1 represents a 4-methoxytrityl, 4, 4'-dimethoxytrityl, or triphenylmethyl group; and B1 represents a cytosine group having a protected amino group. The compound represented by general formula (3) may be, in particular, a protected 2'-deoxycytidine represented by formula (4):
The 2'-deoxycytidine is used as a raw material for antisense DNA.
从含有受保护的 2'-脱氧
胞苷和
水的溶液中沉淀通式 (3) 所代表的
水合晶体形式的受保护的 2'-脱氧
胞苷,并回收受保护的 2'-脱氧
胞苷,从而纯化受保护的 2'-脱氧
胞苷:
其中 R1 代表 4-甲氧基三苯甲基、4,4'-二甲氧基三苯甲基或三苯甲基基团;B1 代表具有受保护
氨基的
胞嘧啶基团。通式(3)代表的化合物尤其可以是由式(4)代表的受保护的 2'-脱氧
胞苷:
2'-脱氧
胞苷可用作反义 DNA 的原料。