vialinin-a and 1-1-diphenyl-2-picrylhydrazyl

While screening for bioactive compounds from edible mushrooms, a new potent antioxidant, vialinin A (1), together with a known compound, ganbajunin B (2), and a mixture of ganbajunins D (3) and E (4), were isolated from the dry fruiting bodies of Thelephora vialis. The structure of 1, 5',6'-bis(phenylacetoxy)-1,1':4',1''-terphenyl-2',3',4,4''-tetraol, was elucidated by spectroscopic and chemical methods. This compound had strong 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical-scavenging activity with an EC(50) value of 14.0 microM, nearly equal to that of butylated hydroxytoluene (BHT; EC(50) = 10.0 microM). A radical scavenging experiment using 1 and DPPH radicals indicated that 1 donated two hydrogen atoms to two molecules of the DPPH radical under hydrophobic conditions.

Topics: Agaricales; Biphenyl Compounds; Chromatography, Gel; Chromatography, High Pressure Liquid; Free Radical Scavengers; Magnetic Resonance Spectroscopy; Picrates; Spectrometry, Mass, Electrospray Ionization; Spectrophotometry, Ultraviolet; Spectroscopy, Fourier Transform Infrared; Terphenyl Compounds