We completed the first total synthesis of puerarin (1), an isoflavone C-glycoside. The key intermediate, β-d-glucopyranosyl-2, 6-dimethoxybenzene (9), was obtained by coupling of a lithiated aromatic reagent (3) with pyranolactone (2) in 56% yield. Condensation of (16) with p-methoxybenzaldehyde gave the chalcone (17). The protected chalcone (18) was cyclized to (19) in the presence of Tl (NO3) 3. Demethylation of (19) was accomplished by refluxing ...
