PROCESS FOR PREPARING NUCLEOSIDE COMPOUND

摘要

A process for producing a nucleoside compound by reacting pentose-1-pohospha te with a nucleic acid base or a nucleic acid base analog in the presence of th e enzymatic activity of nucleoside phosphorylase, wherein a metal salt capable of forming a hardly water-soluble salt with phosphoric acid is added to the reaction system so that the phosphoric acid formed as a by-product is remove d from the reaction system and the equilibrium of the reaction shifts toward t he synthesis of the nucleoside, which makes it possible to give the target nucleoside at a high yield.