METHOD OF PRODUCING ENTECAVIR AND INTERMEDIATE PRODUCTS FOR PRODUCING SAID ENTECAVIR Russian patent published in 2010 - IPC C07D473/18 C07F7/08 C07C43/196 

FIELD: chemistry.

SUBSTANCE: invention relates to a novel improved method of producing entecavir of formula (I) which has antiviral effect for possible use in a medicinal agent with low content of the active component, for example in treating hepatitis B. The invention also relates to novel intermediate products and their methods of production. The entecavir has general formula (I) . Its method of production involves subjecting a compound of formula 7c or its mixture with a compound of formula 8a, where R^b is C₁-C₄alkyl, to oxidation, mainly with a peroxidate, such as a sodium carbonate peroxidate, sodium pyrophosphate peroxidate etc. 7c + 8a. Compound of formula 7c or its mixture with a compound of formula 8a is obtained by bringing the compound of formula 7a into contact with at least one acid selected from halogenated methane-sulphonic acid and possibly methane-sulphonic acid, possibly in the presence of a compound of formula 8a, with subsequent treatment with at least one aqueous base. The invention also relates to production of compounds of formulae 7a and 8a.

EFFECT: increased antiviral effect of the compounds.

27 cl, 8 dwg, 19 ex