Treatment of 1, 2 : 5, 6-di-O-isopropylidene-3-amino-3-deoxy-α-D-allofuranose (1) with trifluoroacetic anhydride afforded crystalline 3-trifluoroacetamido derivative (2) in good yield. Selective removal of the 5, 6-O-isopropylidene group of 2 by treatment with 70% acetic acid followed by oxidation with periodate and subsequent reduction with sodium borohydride gave crystalline 1, 2-O-isopropylidene-3-deoxy-3-trifluoroacetamido-α-D-ribofuranose (3) in good yield. p-Nitrobenzoylation of 3 followed by acetolysis afforded crystalline 1, 2-di-O-acetyl-3-deoxy-3-trifluoroacetamido-5-O-p-nitrobenzoyl-β-D-ribofuranose (5). Coupling of the resulting 1-O-acetyl sugar with bis-trimethylsilylated derivatives of N4-acyl-5-fluorocytosines, N4-acylcytosines, 5-fluorouracil and N4-acetyl-5-methylcytosine using SnCl4 afforded the corresponding fully acylated nucleosides (7). Saponification of 7 gave 3-amino-3-deoxy-β-D-ribonucleosides (8a-8d). Alternatively, 2, 4-dimethoxy-5-methylpyrimidine was also coupled with 5 followed by treatment with ammonia to give 8d. The nucleosides (8a-8d) thus obtained were examined for cytostatic effect on mouse leukemic L5178Y cells. The compounds tested were active against this system and their ED50 values were 0.7 μg/ml, 7 μg/ml, 16 μg/ml and 60 μg/ml, respectively.
1, 2 : 5, 6-二-O-异丙叉-3-
氨基-3-脱氧-α-D-阿洛
呋喃糖(1)经过
三氟乙酸酐处理后,以良好产率得到了晶体状的3-三
氟乙酰胺基衍
生物(2)。通过用70%
乙酸选择性去除2的5, 6-O-异丙叉基团,随后用过
碘酸盐氧化和后续用
硼氢化钠还原,以良好产率得到了晶体状的1, 2-O-异丙叉-3-脱氧-3-三
氟乙酰胺基-α-D-核
呋喃糖(3)。3经过对
硝基苯甲酰化后,再经
乙酸分解处理,得到了晶体状的1, 2-二-O-乙酰-3-脱氧-3-三
氟乙酰胺基-5-O-对
硝基苯甲酰-β-D-核
呋喃糖(5)。利用SnCl4将所得的1-O-乙酰糖与N4-酰基-5-
氟胞嘧啶、N4-酰基
胞嘧啶、5-
氟尿
嘧啶和N4-乙酰-5-甲基
胞嘧啶的双-三甲基
硅基化衍
生物偶联,得到了相应的全酰化核苷(7)。7经过皂化处理后得到了3-
氨基-3-脱氧-β-D-核苷(8a-8d)。此外,2, 4-二甲氧基-5-
甲基嘧啶也与5偶联,随后用
氨处理得到了8d。所得到的核苷(8a-8d)被检测了对小鼠白血病L5178Y细胞的细胞抑制效应。测试的化合物对此系统具有活性,其ED50值分别为0.7 μg/ml、7 μg/ml、16 μg/ml和60 μg/ml。