Restrytisols

Resveratrol (1) could be biotransformed by Botrytis cinerea (a fungal grapevine pathogen) into resveratrol ( )-dehydrodimer (553), resveratrol (Z)-dehydrodimer (556), pallidol, leachianol F (515), and restrytisols A-C (547-549) [249,250]. It has been proved that intestinal bacteria in animals could reductively metabolize stilbene oxide to the corresponding alkenes [380]. 

The retrosynthesis of Aara-e-viniferin (445) by Thomas et al. indicated that the y-butyrolactone (823) was a key intermediate, which later converted from the corresponding stilbene by manganese triacetate-mediated oxidative lactonization (Scheme 18) [407]. In subsequent papers, they described the FeCb-promoted tandem pericyclic synthesis of catechol analogs of restrytisol C. 3,4-Dimethoxy-12-acetoxy stilbene (824), which was synthesized by Heck coupling, was treated with FeCb to give the unnatural stilbene dimers 585 and 586 (Scheme 19) [288]. 

Treatment of 3,4-dimethoxy-12-benzyloxymethyl stilbene under the same condition gave catechol analogs of ampelopsin F and of restrytisol C (587, 588) [289]. 

Resveratrol irawj -dehydrodimer (553) and restrytisol C (549) exerted modest inhibitory activity against COX-1 [250]. The results correlate with the report by Waffo-Teguo et al, which established that resveratrol E) dehydrodimer (553) and its glucoside 554 exhibited nonspecific inhibitory activity against COX-1 and COX-2 [283]. 

Compound (Solvent) Reference restrytisol C (93b) (acetone-d6) 11061 tricuspidatol A (71) (acetone-d6) 1891 viniferifuran (88) (methanol-rf4) 11051... 

Some microbial pathogens can circumvent the defensive response of plants by biotransforming the antimicrobial stilbenoids in a multi-step oxidative detoxification process [106], Research has shown that the pathogenicity of B. cinerea strains is positively correlated with these fungi s production of blue-copper oxidases known as stilbene oxidases or laccases [127,128]. These enzymes are polyphenol oxidases capable of catalyzing the oxidation and polymerization of numerous phenolic substrates [129,130,131,132]. It has been shown that 1 is readily transformed in the presence of B. cinerea culture medium filtrates that contain laccases [107]. Recently, six resveratrol dimers (restrytisols A-C... 

---