stilbenes and 4-hydroxybenzaldehyde

A new oligostilbene, caragasinin C (1), and seven known compounds, betulinic acid (2), 4-hydroxybenzaldehyde (3), (‒)-medicarpin (4), wistin (5), (2E,4S)-4-hydroxy-2-nonenoic acid (6), pallidol (7), and (+)-α-viniferin (8), were isolated from the roots of Caragana sinica. The structure of caragasinin C was established on the basis of spectroscopic techniques, including HRESIMS, 1D and 2D-NMR.

Topics: Benzaldehydes; Caragana; Drugs, Chinese Herbal; Hydroxy Acids; Molecular Structure; Nuclear Magnetic Resonance, Biomolecular; Plant Roots; Polycyclic Compounds; Republic of Korea; Stilbenes

trans-Resveratrol (3,5,4'-trihydroxystilbene) is a natural polyphenolic compound that exhibits antioxidant properties. Our study aimed at studying the HO*-induced oxidation of resveratrol (100 micromol.L(-1)) in aerated aqueous solutions. Gamma radiolysis of water was used to generate HO*/O(2)(*-) free radicals (I = 10 Gy.min(-1), dose = 400 Gy). Oxidation products were identified by direct infusion mass spectrometry and high-performance liquid chromatography/mass spectrometry. For each product, structural elucidation was based on simple mass spectra, fragmentation spectra and deuterium/hydrogen exchange spectra; the comparison with mass spectra of synthetic products provided valuable information allowing the complete identification of the oxidation products. Four products resulting from the direct attack of HO* radicals towards resveratrol were identified respectively as piceatannol (trans-3,5,3',4'-tetrahydroxystilbene), 3,5-dihydroxybenzoic acid, 3,5-dihydroxybenzaldehyde and 4-hydroxybenzaldehyde.

Topics: Benzaldehydes; Chromatography, Liquid; Gamma Rays; Hydroxybenzoates; Oxidation-Reduction; Resorcinols; Resveratrol; Spectrometry, Mass, Electrospray Ionization; Stilbenes; Water