process for preparing the antiviral agent 1s- (1alpha, 3alpha, 4beta) -2-amino-1,9-dihydro-9- 4-hydroxy-3- (hydroxymethyl) -2-methylenocyclopentyl -6h-purin 6-one method of isolation, preparation of ester and compounds thereof

摘要

"process for preparing the antiviral agent [1s- (1alpha, 3alpha, 4beta)] - 2-amino-1,9-dihydro-9- [4-hydroxy3- (hydroxymethyl) -2-methylenocyclopentyl] -6h-purin-6 -one ". the present invention relates to processes for preparing the antiviral agent entecavir. a resin adsorption process for the isolation and purification of entecavir is also disclosed. several intermediates useful in the preparation of entecavir are also disclosed.