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Aim: To reinvestigate the chemical constituents of the ethanolic extract of Meconopsis quintuplinervia Regel which is a traditional Tibetan medicine used for treatments of hepatitis, tuberculosis etc..; Methods: The compounds were enriched by column chromatography techniques over silica gel, macro porous resin and Sephadex LH-20 absorbents, and finally purified by reverse phase preparative HPLC methods with isocratic mobile phase systems of methanol-H2O-acetic acid (500:500:1) and acetonitrile-H2O-acetic acid (200:800:1). Structural determination of the pure compounds were based on extensive analyses of modern spectroscopic methods including IR, MS, HRMS, 1D- and 2D-NMR spectra.; Results: Three alkaloids were obtained and their structures were elucidated as norsanguinarine (I), O-methylflavinantine (II) and 6-methoxy-17-methyl-2, 3-[methylenebis (oxy)]-morphin-5-en-7-one (III).; Conclusion: Norsanguinarine (I) was isolated from genus Meconopsis for the first time, and 6-methoxy-17-methyl-2,3-[methylenebis(oxy)]-morphin-5-en-7-one (III) is a new alkaloid named as meconoquintupline.;
OBJECTIVE: To study the chemical constituents of a Tibetan medicine Meconopsis quintuplinervia.METHOD: Column chromatographic techniques were applied to isolate constituents. A combination of IR, MS and NMR spectroscopy was used to identify structures of constituents.
RESULT: Twelve compounds were isolated from the ethanolic extract and their structures were elucidated as quercetin 3-O-beta-D-glucopyranoside (I), quercetin 3-O-beta-D-galactopyranosyl-(1-->6)-glucopyranoside (II), kaempferol 3-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranoside (III), isorhamnetin 3-0-beta-D-galactopyranosyl-(1-->6)-beta-D-glucopyranoside (IV), caffeic acid (V), protocatechuic acid (VI), p-hydroxycinnamic (VII), 2-(3,4-dihydroxyphenyl )-ethyl-O-beta-D-glucopyranoside (VIII), p-hydroxybenzoyl-beta-D-glucopyranoside (IX), 4-O-beta-D-glucopyranosyl-(Z)-p-coumaric acid (X), 5, 7-dihydroxy-4H-4-chromenone (XI), daucosterol (XII).
CONCLUSION: Ten compounds were isolated from this genus for the first time except for XI and XII.
OBJECTIVE: To study the chemical constituents of Tibetan Madicine Wangla.METHOD: Sepearing the chemical constituents by means of chromatography and identifying their structures on the basis of MS and NMR spectra and TLC with authentic samples.
RESULT: Eight compounds were isolated as 4-[(4-hydroxyphenyl) methoxy]benzenemethanol(I), 4,4'-dihydroxydiphenyl methane(II), 4,4'-dihydroxydibenzyl ether(III), gastrodin(IV), 4-hydroxy benzenemethanol(V), 4-hydroxybenz aldehyde(VI), beta-sitosterol(VII) and beta-daucosterol(VIII).
CONCLUSION: All the compounds were obtained from genus Coeloglassum for the first time. The compound I is a new natural product.
OBJECTIVE: To investigate the xanthones from Tibetan medicine Halenia elliptica and their antioxidant activity.METHODS: Column chromatography over normal phase silica gel, reversed phase silica gel, Sephadex LH-20, and recrystallization techniques were used to isolate and purify constituents from Halenia elliptica. Infrared spectrometry, mass spectrometry, and nuclear magnetic resonance spectrometry were used to identify the structure of compounds. The antioxidant activity was evaluated by measuring the content of malondialdehyde product in mice liver cell microsomal induced by ferrous-cysteine.
RESULTS: Eight xanthones (compound I-VIII) were isolated and identified from the ethyl acetate extract of Halenia elliptica, among which 1,7-dihydroxy-2,3,5-trimethoxyxanthone was a novel compound. Compound I, III at 10 microg/ml and 100 microg/ml could inhibit the production of malondialdehyde in mouse liver microsomes in vitro.
CONCLUSION: Eight xanthones were isolated and they have certain antioxidant activity.