| Bee-collected rape pollen(Brassica campestris L.P) is a hive product that bees pack pollen grains from the flower into pollen pellets on their hind legs with the help of several combs and hairs.Bee-collected rape pollen are known as a rich source of protein, polysaccharide,fatty acid and micromolecule compouds,such as flavonoids and other phenolic compounds.Bee-collected rape pollen has been found to possess a wide range of biological activities,including antioxidant,antitumor and regulating serum lipids. Now,bee-collected rape pollen has been used traditional medicine for the treatment of prostatitis.Bee-collected rape pollen is widely used in China as a health food and an herbal medicine,it is particularly important to study on chemical constituents from bee-collected rape pollen.Bee-collected rape pollen(15kg) extracted under reflux conditions with 95%EtOH. The resulting mixture was suspended in H2O and partitoned successively with petroleum ether,EtOAc and n-BuOH.The compounds were isolated by column chromatography on silical gel;sephadex LH-20 and C18.Their structures were elucidated on the basis of spectral analysis(UV,IR,MS and 1D,2D-NMR) and chemical evidence.Thirteen compounds were isolated from Bee-collected rape pollen and the structures of them were pollenopyrroside A(1),pollenopyrroside B(2),rel-(2R*,5S*)-5-(6,7-dihydroxyethyl)-4-(5'-hydroxymethyl-furan-2'-ylmethylene)-2-ethoxy-dihydrofuran-3-one(3),rel-(2S*,5S*) -5-(6,7-dihydroxyethyl)-4-(5'-hydroxymethyl-furan-2'-ylmethylene)-2-ethoxy-dihydrofuran -3-one(4),kaemferol-3-O-β-D-glucosyl-(2→1)-β-D-glucoside(5), kaemferol-3,4'-di-O-β-D-glucoside(6),quercetin-3-O-β-D-glucosyl-(2→1)-β-glucoside (7),kaemferol(8),trans-p-coumaricacid-4-O-β-D-glucopyranoside(9), 5-hydroxymethylfurfural(10),nicotinic acid(11),nicotinamide(12),β-sitosterol (13).Compounds 1 and 2 represent a unprecedented carbon skeleton with pyrrole ketohexoside derivative;Compounds 3 and 4 were two new furan derivatives. |
PDF Full Text Request