Studies Toward the Total Synthesis of Pluraflavin A.

A synthetic strategy towards the potent cytostatic agent pluraflavin A has been developed. Formation of the enantioenriched anthrapyran core bearing a halogen atom enabled the introduction of the α C-aryl glycoside by Stille cross-coupling and subsequent hydrogenation of the aryl glycal. Chemo- and stereoselective O-glycosylations of α oliose and β 3-epi vancosamine residues afforded a fully glycosylated aromatic core. Attempts to install the dimethylamino group of the C-disaccharide suggest that introduction of an azide group by displacement and subsequent reduction may pave the way to the total synthesis of pluraflavin A.