# Synthesis of Natural and Sugar-Modified Nucleosides Using the Iodine/Triethylsilane System as N-Glycosidation Promoter

## TL;DR

A new method using iodine and triethylsilane efficiently promotes the synthesis of natural and modified nucleosides, including a drug candidate.

## Contribution

The iodine/triethylsilane system is shown to be an effective and selective promoter for N-glycosidation in nucleoside synthesis.

## Key findings

- The Et3SiH/I2 system promotes N-glycosidation with high stereoselectivity in six-membered substrates.
- The method was successfully applied to synthesize the drug apricitabine.

## Abstract

The reagent system based on the combined use of Et3SiH/I2 acts as an efficient N-glycosidation promoter for the synthesis of natural and sugar-modified nucleosides. An analysis of reaction stereoselectivity in the absence of C2-positioned stereodirecting groups revealed high selectivity with six-membered substrates, depending on the nucleophilic character of the nucleobase or based on anomerization reactions. The synthetic utility of the Et3SiH/I2-mediated N-glycosidation reaction was highlighted by its use in the synthesis of the investigational drug apricitabine.