D-Thr(tBu)-OH

[1S-(1α,3α,4β)]-2-Amino-1,9-dihydro-9-[2-methylene-4-(phenylmethoxy)-3-[(phenyl-methoxy)methyl]cyclopentyl]-6H-purin-6-one

(1s,3r,4s)-2-amino-9-[4-(benzyloxy)-3-(benzyloxymethyl)-2-methylidene-cyclopentyl]-3h-purin-6-one

entecavir-9

2-amino-9-((1s,3r,4s)-4-(benzyloxy)-3-(benzyloxymethyl)-2-methylenecyclopentyl)-1h-purin-6(9h)-one

entecavir e8

2-amino-9-((1s,3r,4s)-4-(benzyloxy)-3-(benzyloxymethyl)-2-methylenecyclopentyl)-9h-purin-6-ol

entecavir intermediate viii isomer

2-Amino-1,9-dihydro-9-[(1S,3R,4S)-4-(benzyloxy)-3-(benzyloxymethyl)-2-methylenecyclopentyl]-6H-purin-6-one

(1S,3R,4S)-2-amino-9-[4-(benzyloxy)-3-(benzyloxymethyl)-2-methylidene-cyclopentyl]-3H-purin-6-one

Entecavir intermediate N8

10-Oxy Iminostilbene Carbonyl Chloride

Entecavir intermediate N-1

2-amino-9-{(1S,3R,4S)-4-(benzyloxy)-3-[(benzyloxy)methyl]-2-methylidenecyclopentyl}-1,9-dihydro-6H-purin-6-one

2-amino-9-((1S,3R,4S)-4-(benzyloxy)-3-(benzyloxymethyl)-2-methylenecyclopentyl)-9H-purin-6-ol

The interm