for the following products
(1S,3R,4S)-2-Amino-9-[4-(benzyloxy)-3-(benzyloxymethyl)-2-methylidene-cyclopentyl]-3H-purin-6-one | 2-Amino-1,9-dihydro-9-[(1S,3R,4S)-2-methylene-4-(phenylmethoxy)-3-[(phenylmethoxy)methyl]cyclopentyl]-6H-purin-6-one | Entecavir intermediate 8 and 2-Amino-1,9-dihydro-9-[(1S,3R,4S)-4-(benzyloxy)-3-(benzyloxymethyl)-2-methylenecyclopentyl]-6H-purin-6-one
