Study On Chemical Constituents And Bioactivities From Rhododendron Micranthum Turcz

Rhododendron micranthum Turcz, belongs to Ericaceae, Rhododendron, branched shrubs, its branches always make medicine. Volatile oils, tannins, saponins, reducing substances, oils, flavonoids and polysaccharides was found in it, with the effect of removing pathogenic wind and dampness, promoting blood circulation to remove meridian obstruction, resolving phlegm to relieve cough.The reports of chemical composition of the Rhododendron micranthum Turcz focused on flavonoids in China, beyond that there is no study on the chemical composition systematically. Many kinds of extractive technology, such as normal phase/reversed phase silica gelcolumn chromatography, preparation thin layer chromatography, HPLC, recrystallization, Sephadex LH-20/60 had been used. There are 18 compounds were separated and identified in all. They are: lupeol acetate(1), germacrone(2), lupenone(3), lupeol(4), 5-hydroxy-7-methoxy-2-(4-met hoxyphenyl)-6-methyl-4H-chromene-4-ketones(5),β-sitosterol(6), 6,10,14-trimethylpentadec ane-2-ketone(7), 3-hydroxy-30-down-lupine-alkyl-20-ketone(8), 3-hydroxy-11-en-11,12-dehy drogenation-28,13-oic-acid-lactone(9), hydroxybenzaldehyde(10), uvaol(11), betulinic acid (12), 2-(hydroxymethyl)-phenol(13), 3,11-dihydroxy-12-en-12,13-dehydrogenation-ursane(1 4), 6β-hydroxy-4-en-3-stigmast ketones(15),β-hydroxy-5-en-7-stigmast ketones(16), skimme tine(17), oleanolic acid(18). These compounds are first discovered in Rhododendron micran thum Turcz, compound 1,2,3,4,5,7,8,9,14 are first discovered in Rhododendron.This paper also made the compounds 3,4,7,8,9,10,11,13,15,17 of anti-tumor activity research. Compounds 4 and 11 have some inhibitory activity to HepG-2 cells, while other compounds have little antitumor activity.