Entecavir USP Impurity B

Chemical Name: 9-[(1R ,3R ,4S )-4-Hydroxy-3-(hydroxymethyl)-2-methylenecyclopentyl]guanine

Synonym: Doxycycline USP RC A ; 6-epidoxycycline ; (4S,4aR,5S,5aR,6S,12aS)-4-(Dimethylamino)-3,5,10,12,12a-pentahydroxy-6-methyl-1,11-dioxo-1,4,4a,5,5a,6,11,12a-octahydrotetracene-2-carboxamide