guajavarin and kaempferol

We investigated the chemical constituents of the leaves of Psidum littorale, which include 16 flavonoids, including seven flavonols, six flavonoid glycosides and three flavonones. The compounds were isolated by silica gel column chromatography. Their structures were elucidated on the basis of spectral analysis and by comparison with published data. Seven flavonols were kaempferol (1), isorhamnetin (2), myricetin- 3,7,3’-trimethyl ether(3), laricitrin (4), quercetin (5), myricetin (6) and quercein-3,4’-dimethyl ether (7), six flavonoid glycosides were guaijaverin (8), hyperoside (9), 5,4’-dyhydroxy-3,7,5’-methoxyflavone-3’-O-β-D- glucoside (10), laricitrin-3-O-xyloside (11), myricetin-3-O-α-L-rhamnopyranoside (12) and myricetin-3-O-β-D- xyloside (13). Three flavonones were 4’-O-methyldihydroquercetin (14), dihydroapigenin (15) and ampelopsin 4’-O-β-D-glucopyranoside (16). Compound 10 is a new chemical, compounds 2-4, 7, 10-16 were first isolated from this plant. (1)H NMR and (13)C NMR data of compound 11 were not reported in literature.

Topics: Flavonoids; Flavonols; Glycosides; Kaempferols; Plant Leaves; Psidium; Quercetin

A new acylated avicularin, namely avicularin 2''-(4'''-O-n-pentanoyl)-gallate (1) along with 12 metabolites have been isolated from the ethyl acetate extract of the aerial parts of Jussiaea repens L. (Onagraceae). Their structures were established as trifolin 2''-O-gallate (2), quercetrin (3), guaijaverin (4), reynoutrin (5), juglanin (6), avicularin (7), hyperin (8), trifolin (9), hyperin 2''-O-gallate (10), rutin (11), kaempferol (12) and quercetin (13) on the basis of their chromatographic properties, chemical and spectroscopic evidences. The investigated ethyl acetate extract was found to be non-toxic (LD(50) up to the maximum soluble dose 4 g kg(-1) body wt.) and had significant antioxidant, hepatoprotective, anti-inflammatory and antidiabetic activities. Also some of the isolated flavonoids showed cytotoxic activity against Ehrlich ascitis carcinoma cells.

Topics: Animals; Anti-Inflammatory Agents; Antioxidants; Flavonoids; Galactosides; Hypoglycemic Agents; Kaempferols; Magnetic Resonance Spectroscopy; Male; Mice; Molecular Structure; Onagraceae; Plant Extracts; Quercetin; Rats