NEW CYCLOBUTANE DERIVATIVE

摘要

PURPOSE:To provide the subject new compound useful as an antiviral agent. CONSTITUTION:The compound of formula I (B is nucleic acid base derivative; R<1> is 1-6C alkyl; R<2> and R<3> are H or OH-protecting group), e.g. 9-[(1beta,2alpha,3beta)-2-(1- hydroxyethyl)-3-hydroxymethyl-1-cyclobutyl]guanine. The compound of formula I can be produced by reacting a compound of formula II with 2amino-6- halogeno-3,4-dihydro-4-oxo-5-nitropyridine in an inert solvent (e.g. methanol or DMF) in the presence of a tertiary amine (e.g. triethylamine), reducing the nitro group of the resultant compound of formula III with a reducing agent such as zinc powder in an acidic solvent such as formic acid to obtain a compound of formula IV and reacting the compound with a tri(1-4C)alkyl orthoformate such as trimethyl orthoformate.