A Scalable Biomimetic Synthesis of Resveratrol Dimers and Systematic Evaluation of their Antioxidant Activities

Abstract

An efficient synthetic route to quadrangularin A and pallidol is reported, featuring a scalable biomimetic oxidative dimerization that proceeds in excellent yield and with complete regioselectivity. A systematic evaluation of the natural products and their synthetic precursors as radical-trapping antioxidants is presented, providing insight to the properties relevant to their purported biological activities. Keywords resveratrol; antioxidants; quinone methide; pallidol; quadrangularin A The resveratrol (1) oligomers are a diverse set of polyphenolic natural products whose stress factor-induced biosynthesis constitutes an important chemical defense mechanism in many

Comparative Study of Secreted Proteins, Enzymatic Activities of Wood Degradation and Stilbene Metabolization in Grapevine Botryosphaeria Dieback Fungi

“…Pallidol: HRESI MS (−) m/z 453.1337 [M−H] − (calcd for C 28 H 21 O 6 453.1338) 499.1315 [M+HCOOH-H] − (calcd for C 29 H 22 O 8 498.1315); FTIR (ATR) ν max cm −1 : 3323, 1601, 1511, 1464, 1344, 1173, 1129, 836; 1 H NMR (400 MHz, acetone-d6) δ = 7.6–8.4 (6 H, br), 6.98 (4 H, d, J = 8.6 Hz), 6.70 (4 H, d, J = 8.6 Hz), 6.62 (2 H, d, J = 1.8 Hz), 6.19 (2 H, d, J = 1.9 Hz), 4.57 (2H, s), 3.81 (2 H, s); 13 H NMR (100 MHz, acetone-d6) δ = 159.41, 156.41, 155.40, 150.40, 137.82, 129.12, 123;33, 115.89, 103.42, 102.56, 60.58, 54.04. Spectral data are in agreement with the literature [ 49 , 50 ].…”

Enzyme-promoted oxidative cross-coupling for the synthesis of oxyresveratrol-related heterodimers

“…The dihydrobenzofuran skeleton of heterodimer 12 was established on the basis of 1 H and 13 C NMR spectroscopy as well as by HRMS. The connectivity of the two heteromonomer units in dimer 12 was further confirmed by X-ray crystallographic analysis.…”

“…[1][2][3][4][5][6][7][8][9] Numerous efforts have been devoted to synthesizing these homooligomeric products, especially oligomers of 1 for investigating their structure-activity relationships, and significant achievements had been made over the past 40 years. [10][11][12][13][14] However, little attention has been paid to the small number of heterooligomers polymerized from different stilbene monomers, such as the heterodimers 5−8. 5,7,15 Only a few efforts to synthesize these dimers have been made so far, which included FeCl 3 •6H 2 Ocatalysed oxidative cross-coupling reactions of stilbenes 1 and 2 conducted by Lin's group, 2 and enzyme-mediated biotransformation of the mixture of 1 and pterostilbene studied by Queiroz's team.…”