PROCESS AND INTERMEDIATES FOR THE SYNTHESIS OF ENTECAVIR

摘要

The invention refers to a method for isolating entecavir or an entecavir intermediate from a diluted mixture, the diluted mixture comprising entecavir and water or a mixture comprising an entecavir intermediate and other process reagents comprising:
(a) adsorbing the diluted mixture onto a hydrophobic resin bed;
(b) washing the resin bed with water to remove salt; and
(c) eluting the entecavir or entecavir intermediate from the resin bed with an organic solvent.