Davidiol A

Stilbenes with potent cytotoxicity from the seedcases of Paeonia suffruticosa Andrews.[Pubmed:36403670]

Phytochemistry. 2023 Jan;205:113515.

Stilbenes (based on the 1,2-diphenylethylene skeleton) are a class of plant polyphenols with rich structural and bioactive diversity. Twenty-six stilbenes, including five undescribed compounds (7,8-dioxy-4,3',5'-trihydroxystilbene, trans-13'-methoxygnetin H, suffruticosol E, paestibenetrimerols A and B), were isolated from the seedcases of Paeonia suffruticosa Andrews. Their structures were elucidated by spectroscopic analyses and comparison with previously reported data. The absolute configurations of trans-13'-methoxygnetin H, suffruticosol E, paestibenetrimerols A and B were assigned from their respective electronic circular dichroism (ECD) spectra. Additionally, the structures of known compounds suffruticosols A, B and rockiol B were revised and the absolute configurations of them, and along with (+)-Davidiol A, were also further determined by ECD. The isolated compounds, trans-gnetin H, cis-gnetin H and suffruticosol E, were found to have potent cytotoxicity against the DU-145 and MDA-MB-231 cell lines with IC(50) values of 4.89-8.61 muM. The preliminary antitumor structure-activity relationship of these stilbenes is discussed as well.

Polyphenols isolated from leaves of Vitis thunbergii var. taiwaniana regulate APP related pathway.[Pubmed:26675439]

Bioorg Med Chem Lett. 2016 Jan 15;26(2):505-511.

Alzheimer's disease (AD) is a neurodegenerative disorder characterized by the accumulation of amyloid plaques and neurofibrillary tangles in the brain. The major component of the plaques, amyloid-beta (Abeta), is generated from amyloid-beta precursor protein (APP) by beta- and gamma-secretase-mediated cleavages. Multiple lines of evidence demonstrate that overproduction/accumulation of Abeta in vulnerable brain regions is a primary cause of the pathogenesis of AD. Among the twelve polyphenols isolated from the leaf extracts of Vitis thunbergii var. taiwaniana (VTT), stenophyllol C, stenophyllol B, ampelopsin C, vitisin A, and Davidiol A were shown to significantly reduce both Abeta40 and Abeta42 levels in N2a695 cells. Further studies revealed that ampelopsin C and vitisin A reduce Abeta production through inhibiting beta-secretase activity, while the effects of the other active polyphenols on reducing Abeta generation are through different mechanisms. These results suggest that VTT extracts may be beneficial for AD prevention and treatment.

Viniphenol A, a complex resveratrol hexamer from Vitis vinifera stalks: structural elucidation and protective effects against amyloid-beta-induced toxicity in PC12 cells.[Pubmed:24521157]

J Nat Prod. 2014 Feb 28;77(2):213-7.

Stilbenes have received much attention during the last two decades following the discovery of resveratrol in wine. Since then, there have been a growing number of papers reporting various biological activities of naturally occurring stilbenes. The aim of this study was to determine new minor stilbenes from Vitis vinifera stalks. Purification of these compounds was achieved by means of centrifugal partition chromatography, a versatile separation technique that does not require a solid stationary phase. Viniphenol A (1), a new resveratrol hexamer, was isolated along with five oligostilbenoids identified in V. vinifera for the first time, ampelopsin C, Davidiol A, leachianol F, leachianol G, and E-maackin, a dimer with an unusual dioxane moiety, and 14 known hydroxystilbenes. The structure and stereochemistry of viniphenol A were determined on the basis of spectroscopic data analysis and molecular modeling under NMR constraints. Viniphenol A showed protective effects against amyloid-beta-induced toxicity in PC12 cell cultures.