Isolation, structural determination of flavonoids and ellagic acid derivatives from the leaves of Cleistanthus eberhardtii

From the leaves of Cleistanthus eberhardtii (Gagnep.) Croizat, six known compounds were isolated, including four flavonoids amentoflavone (1), isoquercetrin (2), astragalin (3), kaempferol (4), and two ellagic acid derivatives 3,3′-O-dimethylellagic acid-4′-O-α-L-rhamnopyranoside (5) 3,3′-O-dimethylellagic acid-4′-O-β-D-glucopyranoside (6). The structures of these compounds were determined through MS and NMR spectra analyses, and comparison with literature data. To date, this is the first phytochemical investigation of the leaves of C. eberhardtii.