Sekine M, Hata T
Nucleic Acids Symp Ser. 1985(16):185-8.
A synthetic strategy for branched ribonucleotides, which have recently been discovered, was described. A fully protected adenosine unit (5) having the tris (4,5-dichlorophthalimido)trityl (CPTr), bis(anilino)phosphoryl (BAP), and bis(phenylthio)phosphoryl (BPTP) groups as the 5'-, 2'-, and 3'-hydroxyl protecting groups, respectively, was synthesized from adenosine by a five-step reaction involving a new method for the 2'-O-phosphorylation by the use of hexaethylphosphorous triamide. The selective deprotection of appropriate protecting groups from 5 followed by stepwise condensation with two different ribonucleoside derivatives (7 and 10) gave a protected branched ribonucleotide (11) via a 3'-phosphorylated 2'-5' dinucleotide (8). Deprotection of 11 and 8 gave a branched trinucleotide (12) and 3'-phosphorylated dinucleotide (13).
描述了一种针对最近发现的支链核糖核苷酸的合成策略。通过五步反应从腺苷合成了一个完全受保护的腺苷单元（5），该单元分别具有三（4,5 - 二氯邻苯二甲酰亚胺基）三苯甲基（CPTr）、双（苯胺基）磷酰基（BAP）和双（苯硫基）磷酰基（BPTP）基团作为5'-、2'-和3'-羟基保护基团，其中涉及一种使用六乙基磷三酰胺进行2'-O-磷酸化的新方法。从5中选择性地脱去适当的保护基团，然后与两种不同的核糖核苷衍生物（7和10）逐步缩合，通过3'-磷酸化的2'-5'二核苷酸（8）得到一个受保护的支链核糖核苷酸（11）。对11和8进行脱保护得到一个支链三核苷酸（12）和3'-磷酸化二核苷酸（13）。
