NOVEL METHOD FOR PREPARING ENTECAVIR AND INTERMEDIATE USED THEREIN

摘要

PURPOSE: A novel method for preparing entecavir and a novel intermediate used for the same are provided to easily produce a large amount of novel intermediates. CONSTITUTION: A method for preparing entecavir of chemical formula 1: a step of hydrolyzing alpha-exomethylene compound of chemical formula 2 to synthesize a compound of chemical formula 3; a step of reacting the compound of chemical formula 3 with a purine compound of chemical formula 4 by Mitsunobu reaction to obtain a nucleoside compound of chemical formula 5; a step of reacting the compound of chemical formula 5 with tetrabutyl ammonium fluoride to obtain a compound of chemical formula 6; and a step of hydrolyzing the compound of chemical formula 6.