Oxacyclohexadeca-3,11,13-triene-2,10-dione,15-[[(6-deoxy-2,3-di-O-methyl-â-Dallopyranosyl) oxy]methyl]-16-ethyl-5,7,9- trimethyl-6-[[3,4,6-trideoxy-3-(dimethylamino)- â-D-xylo-hexopyranosy