Chemical name: 2-Amino-1,9-dihydro-9-[(1S,3R,4S)-4-hydroxy-3-(hydroxymethyl)-2-methylenecyclopentyl]-6H-purin-6-one CAS No.: 142217-69-4 Formula: C12H15N5O3 Appearance: White to off-white powder Assay: Not less than 99.5% Package: 1kg/pack; Category: Anti-HBV; Nucleoside anolog