Regioselective oxidative coupling of 4-hydroxystilbenes: synthesis of resveratrol and epsilon-viniferin (E)-dehydrodimers.
Treatment of 5-[2-(4-hydroxyphenyl)vinyl]benzene-1,3-diol (resveratrol) with an equimolar amount of silver(I) acetate in dry MeOH at 50 degrees C for 1 h followed by chromatographic purification with a short silica gel column allowed the isolation of its (E)-dehydrodimer, 5-[5-[2-(3,5-dihydroxyphenyl)vinyl]-2-(4-hydroxyphenyl)-2,3-dihydrobenzofuran-3-yl]benzene-1,3-diol, as a racemic mixture in high yield. The present method was applicable to the oxidative dimerization of 4-hydroxystilbenes such as trans-styrylphenol and 5-[6-hydroxy-2-(4-hydroxyphenyl)-4-[2-(4-hydroxyphenyl)vinyl]-2,3-dihydrobenzofuran-3-yl]benzene-1,3-diol (epsilon-viniferin) leading to the corresponding 2-(4-hydroxyphenyl)-2,3-dihydrobenzofurans possessing various types of biological activities.
Sako
Magoichi
M
Gifu Pharmaceutical University, 5-6-1, Mitahora-higashi, Gifu 502-8585, Japan. sako@gifu-pu.ac.jp
Hosokawa
Hiroyuki
H
Ito
Tetsuro
T
Iinuma
Munekazu
M
D001572:Benzofurans / Q000138:chemical synthesis* / Q000737:chemistry*; D002384:Catalysis; D020650:Combinatorial Chemistry Techniques; D007202:Indicators and Reagents; D015394:Molecular Structure; D010084:Oxidation-Reduction; D000077185:Resveratrol; D013237:Stereoisomerism; D013267:Stilbenes / Q000138:chemical synthesis* / Q000737:chemistry*
D001572:Benzofurans; D007202:Indicators and Reagents; D013267:Stilbenes; C091891:epsilon-viniferin; D000077185:Resveratrol