1,6,11-Trihydroxy-3-methyl-7,12-dioxo-5,6,7,12-tetrahydrobenzo[a]anthracen-8-yl 2,6-dideoxy-4-O-(2,6-dideoxy-3-O-(5-((2,6-dideoxy-4-O-(2,6-dideoxy-3-O-(5-hydroxy-6-methyltetrahydro-2H-pyran-2-yl)hexop\tyranosyl)hexopyranosyl)oxy)-6-methyltetrahydro-2H-pyran-2-yl)hexopyranosyl)hexopyranoside AIDS-136708 AIDS136708 Landomycin A NSC639187