N-(N2-lysinomethyl)tetracycline; (2Z,4S,4aS,5aS,6S,12aS)-2-[amino(hydroxy)methylidene]-7-chloro-4-(dimethylamino)-6,10,11,12a-tetrahydroxy-6-methyl-4a,5a,6,12a-tetrahydrotetracene-1,3,12(2H,4H,5H)-trione; N~2~-({[(Z)-[(4aS,6S,12aS)-4-(dimethylamino)-6,10,11,12a-tetrahydroxy-6-methyl-1,3,12-trioxo-3,4,4a,5,5a,6,12,12a-octahydrotetracen-2(1H)-ylidene](hydroxy)methyl]amino}methyl)lysine; N~2~-({[(E)-[(4S,4aS,6S,12aS)-4-(dimethylamino)-6,10,11,12a-tetrahydroxy-6-methyl-1,3,12-trioxo-3,4,4a,5,5a,6,12,12a-octahydrotetracen-2(1H)-ylidene](hydroxy)methyl]amino}methyl)lysine