and 17, useful intermediates toward the angucyclines, either benz[a]anthraquinone-type or naphthacenequinone-type, has been developed based on (1) the O→C-glycoside rearrangement and (2) the regioselective cycloaddition of α-alkoxybenzyne and α-oxyfuran. The first totalsynthesis of galtamycinone (2), the common aglycon of naphthacenequinone-type angucyclines, has been achieved by utilizing 17 as the