2-Naphthacenecarboxylic acid, 3-((6-deoxy-2,3,4-tri-O-methyl-alpha-L-mannopyranosyl)oxy)-6,6a,7,10,10a,11-hexahydro-6a,7,12-trihydroxy-8,10a-dimethoxy-1-methyl-6,10,11-trioxo-, methyl ester, (6aR-(6aalpha,7alpha,10aalpha))-