(4S)-Anhydrotetracycline 1665-56-1 2-Naphthacenecarboxamide, 1,4,4a,5,12,12a-hexahydro-4-(dimethylamino)-1,12-dioxo-6-methyl-3,10,11,12a-tetrahydroxy-, (4S-(4-alpha,4a-alpha,12a-alpha))- 5a,6-Anhydrotetracycline Anhydrotetracycline