Isolation and identification of a new homoisoflavan with potent antioxidant activity from commelina elegans

Potent antioxidative compounds have been isolated from the ethyl acetate extract of Commelina elegans, Commelinaceae, using a repeated column chromatography. On the basis of spectral analyses, the compounds were identified as brazilin, brazilein and the new homoisoflavan-3, 7, 9, 3', 4'-ol [4-4] dimer with X- and Y-conformers. The compounds inhibited both enzymatic lipid peroxidation using rat liver microsomes and mitochondria and non-enzymatic reactions. The compounds completely protected the activities of the mitochondrial enzymes NADH- and succinate-cytochrome c reductase. Furthermore, the radical scavenging activity on enzymatically and non-enzymatically generated superoxide anion was investigated. Electron spin resonance using the spin trapping method suggested that the compounds have potent superoxide anion scavenging activities

Montanone, a new sesquiterpene from jasonia montana

The aerial parts of Jasonia montana afforded a new isoiphionane sesquiterpene, montanone 1. The structure of 1 was elucidated to be 11, 15-dihydroxy-iphionane-4-one by high field 1D and 2D NMR techniques, including HMQC, NOESY and HMBC