4-dichloro-5-[2,3-O-isopropylidene-5-O-(t-butyl)dimethylsilyl-β-D-ribofuranosyl]-5H-pyrrolo[3,2-d]pyrimidine (4), along with a small amount of the corresponding α anomer, 5. Compound 4 served as the versatile intermediate from which the N-7 ribofuranosyl analogs of the naturally-occurring purine nucleosides adenosine, inosine and guanosine were synthesized. Thus, controlled amination of 4 followed by sugar deprotection
通过2,4-二
氯-5 H-
吡咯并[3,2 ]的单相钠盐糖基化反应制备了几个N -5
呋喃呋喃糖基-2,4-二取代的
吡咯并[3,2- d ]
嘧啶(9-脱氮
嘌呤)核苷。- d ]
嘧啶(3使用1-
氯-2,3-)ö异亚丙基-5- ö - (吨丁基)dirnethylsilyl-α-d
呋喃核糖(2)。使用2进行糖基化避免了“原酰胺”产物1的形成,并提供了出色的β核苷2,4,2-二
氯-5- [2,3 - O-异亚丙基-5- O-(t-丁基)二甲基甲
硅烷基-β-D-
呋喃呋喃糖基] -5 H-
吡咯并[3,2- d ]
嘧啶(4),以及少量相应的α异构体5。化合物4用作通用中间体,从该中间体可以合成天然存在的
嘌呤核苷
腺苷,
肌苷和
鸟苷的N -7核
呋喃糖基类似物。因此,控制
氨基化4,然后进行糖脱保护和脱卤,得到作为盐酸盐的
腺苷类似物4-
氨基-5-β-D-
呋喃呋喃糖基-5 H-
吡咯并[3,2- d ]
嘧啶(8)。碱
水