The synthesis of methyl 3-azido-5-benzoyl-2,3-dideoxy-β-D-ribofuranoside (10) from methyl 2-deoxy-D-ribofuranoside (1) and its use for the preparation of 3'-azido-2',3'-dideoxy-β-D-ribofuranosides is described. Reaction of methylglucoside 1 with benzoyl chloride in pyridine afforded 5-O-benzoyl derivative 2, which on oxidation with complex of chromium trioxide, pyridine and acetic anhydride afforded 3-keto derivative 3. This was reduced with sodium borohydride in ethanol to give a mixture of methyl 2-deoxyglycosides of α-D-ribo- (4) and β-D-xylo- (5) configuration. Their mesyl derivatives 6 and 7 were chromatographically separated. Compound 7 reacted with sodium azide in hot dimethylformamide to afford methyl 3-azido-5-O-benzoyl-2,3-dideoxy-β-D-ribofuranoside (10). 5-Phenyl-2(1H)-pyrimidinone was converted into silyl derivative 11 by treatment with hexamethyldisilazane. Reaction of compound 11 with the azido sugar 10, catalyzed by trimethylsilyl trifluoromethanesulfonate, and subsequent methanolysis, furnished a mixture of anomeric 3'-azido-2',3'-dideoxynucleosides 14 and 15. Methyl 5-O-benzoyl-2,3-dideoxy-α-D-ribofuranoside (17) was prepared from methyl-α-glycoside 4 by reaction with thionyl chloride and subsequent reduction of the obtained 3-chloro derivative 16 with tributylstannane. Silyl derivative 11 reacted with 2,3-dideoxy sugar 17 under catalysis with trimethylsilyl triflate to give mainly 1-(5-O-benzoyl-2,3-dideoxy-α-D-glycero-pentofuranosyl)-5-phenyl-2(1H)-pyrimidinone (19) and minor amount of the β-anomer 18. Their methanolysis afforded dideoxynucleosides 20 and 21.
本文描述了从甲基2-去氧-
D-核糖呋喃苷(1)合成甲基3-
叠氮基-5-苯甲酰基-2,3-二去氧-β-
D-核糖呋喃苷(10)并用于制备3'-
叠氮基-2',3'-二去氧-β-
D-核糖呋喃苷的方法。将
甲基葡萄糖苷1与
苯甲酰氯在
吡啶中反应得到5-O-苯甲酰衍
生物2,然后在
铬酸三氧化物、
吡啶和
乙酸酐的复合物的氧化下得到3-酮衍
生物3。用
乙醇中的
硼氢化钠还原3,得到α-
D-核糖和β-
D-木糖构型的甲基2-去氧
葡萄糖苷的混合物4和5。它们的甲磺酰衍
生物6和7被色谱分离。化合物7在热二甲基甲酰胺中与
叠氮化
钠反应,得到甲基3-
叠氮基-5-O-苯甲酰基-2,3-二去氧-β-
D-核糖呋喃苷(10)。将5-苯基-2(1H)-
嘧啶酮转化为
硅烷衍
生物11,通过
六甲基二硅氮烷的处理。化合物11与
叠氮糖10在三甲基
硅基
三氟甲磺酸催化下反应,随后进行
甲醇解,得到异构体3'-
叠氮基-2',3'-二去氧核苷14和15的混合物。甲基5-O-苯甲酰基-2,3-二去氧-α-
D-核糖呋喃苷(17)由甲基-α-糖苷4与
硫酰氯反应,然后用三
丁基锡还原所得的3-
氯衍
生物16制备而成。
硅烷衍
生物11与2,3-二去氧糖17在三甲基
硅基
三氟甲磺酸催化下反应,主要得到1-(5-O-苯甲酰基-2,3-二去氧-α-D-巨环糖基)-5-苯基-2(1H)-
嘧啶酮(19)和少量的β-异构体18。它们的
甲醇解得到二去氧核苷20和21。