Abstract Nucleobase-anion glycosylation (KOH, tris [2-(2-methoxyethoxy) ethyl] amine (TDA- 1), MeCN) of the pyrrolo [2, 3-d] pyrimidines 4a–d with 5-O-[(1, 1-dimethylethyl) dimethylsilyl]- 2, 3-O-(1-methylethylidene)-α-D-ribo-furanosyl chloride (5) gave the protected β-D- nucleosides 6a–d stereoselectively (Scheme 1). Contrary, the β-D-halogenose 8 yielded the corresponding α-D-nucleosides (9a and 9b) apart from minor amounts of the β-D-anomers ...
![2-Amino-4-chloro-7-(2,3-O-isopropylidene-5-O-tert-butyldimethylsily--D-ribofuranosyl)pyrrolo[2,3,-d]pyrimidine Structure](https://image.chemsrc.com/caspic/315/115479-40-8.png)
![2-amino-4-chloro-7-(β-D-ribofuranosyl)-7H-pyrrolo[2,3-d]pyrimidine Structure](https://image.chemsrc.com/caspic/124/120401-36-7.png)
![5-O-[(1,1-dimethylethyl)dimethylsilyl]-2,3-O-(1-methylethylidene)-β-D-ribofuranosyl chloride Structure](https://image.chemsrc.com/caspic/051/102690-95-9.png)