Solid-liquid phase-transfer glycosylation (KOH, tris[2-(2-methoxyethoxy)ethye]amine ( = TDA-1), MeCN) of pyrrolo[2,3-d]pyrimidines such as 3a and 3b with an equimolar amount of 5-O-[(1,1 -dimethylethyl)dimethylsilyl]-2,3-O-(1-methylethylidene)-α-D-ribofuranosyl chloride (1) [6] gave the protected β-D-nucleosides 4a and 4b, respectively, stereoselectively (Scheme). The β-D-anomer 2 [6] yielded the corresponding
固-液相转移的糖基化(KOH,三[2-(
2-甲氧基乙
氧基)ethye]胺(T
DA =-1),MeCN中)
吡咯并[2,3的d ]
嘧啶类,例如图3a和3b中与等摩尔量5- O -[(1,1-二
甲基乙基)二
甲基甲
硅烷基] -2,3 - O-(
1-甲基亚乙基)-α-D-
呋喃呋喃糖基
氯(1)的制备[6]得到了保护的β-D-核苷4a和图4b分别是立体选择性地(方案)。β-D-异头物2 [6]得到相应的带有痕量β-D-化合物的α-D-核苷5a和5b。6-取代的7-
脱氮嘌呤核苷6a,7a和8被转化为结核菌素(10)或其α-D-异头物(11)。异头
核糖核苷自旋-晶格弛豫测量表明Ť 1个在α-d系列HC的值(8)的增加相比,HC(8)在β-d系列显著而相对的对为真Ť 1的HC(1')。分配了6个取代的7-
脱氮嘌呤D-核
呋喃糖苷的15 N-NMR数据,并将其与2'-
脱氧化合物的15 N-NMR数据进行了比较。此