3-methylquercetin and isovaleric-acid

Eight undescribed isorhamnetin glycosides, acylated with isovaleric acid were isolated from the fruit of sea buckthorn (Elaeagnus rhamnoides (L.) A. Nelson). Structures of the purified compounds were determined using one and two-dimensional NMR spectroscopy, mass spectrometry and chemical methods. In addition, the cytotoxic activity of the phenolic-rich fraction of sea buckthorn fruit and its major flavonoids against colon cell lines, HT-29, HCT-116 and Caco-2, was determined. While the phenolic fraction was moderately active against HT-29 and HCT-116, all investigated purified flavonoids showed significantly weaker activity. This is most probably the first report about isorhamnetin glycosides acylated with isovaleric acid.

Topics: Cell Survival; Dose-Response Relationship, Drug; Fruit; Glycosides; Hemiterpenes; Hippophae; Humans; Molecular Conformation; Pentanoic Acids; Poland; Quercetin; Structure-Activity Relationship; Tumor Cells, Cultured