Synthesis of a C-glycosylpyranonaphthoquinone related to medermycin

The synthesis of a 2-deoxyglucosyl analogue 2 of the pyranonaphthoquinone antibiotic medermycin 1 is reported. The critical β C-glycoside linkage was introduced at an early stage in the synthesis by direct C-glycosylation of naphthol 7 with benzyl protected glycosyl donor 4. Conversion of C-glycoside 8 to 2-acetyl-1,4-naphthoquinone 3 then allowed assembly of the pyranonaphthoquinone skeleton via a furofuran annulation–oxidative rearrangement strategy.