1-Naphthacenecarboxylic acid, 2-ethyl-1,2,3,4,6,11-hexahydro-2,5,7,12-tetrahydroxy-6,11-dioxo-4-((2,3,6-trideoxy-4-O-(2,6-dideoxy-alpha-L-lyxo-hexopyranosyl)-3-(dimethylamino)-alpha-L-lyxo-hexopyranosyl)oxy)-, methyl ester