Article

Novel synthesis of flavonoids of Scutellaria baicalensis Georgi.

School of Pharmacy, National Defense Medical Center, Taiwan.
CHEMICAL & PHARMACEUTICAL BULLETIN (Impact Factor: 1.56). 04/2003; 51(3):339-40. DOI: 10.1248/cpb.51.339
Source: PubMed

ABSTRACT A concise and efficient total synthesis of the flavonoids baicalein, oroxylin A and wogonin was described. Intramolecular oxidative cyclization followed by demethylation of chalcone 1, readily prepared from trimethoxyphenol, afforded, depending upon the controlled conditions, baicalein or oroxylin A in excellent yields. Demethylation of 1 yielded 3, which, by oxidation with I(2)/dimethyl sulfoxide (DMSO), was readily converted to oroxylin A and wogonin after column chromatography.

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