Triterpenoids isolated from leaves of Ledum palustre / 中草药

Objective: To study the chemical constituents from the leaves of Ledum palustre and their antitumor activities. Methods: The chemical constituents were isolated and purified by chromatography of silica gel column, recrystallization and HPLC, and their structures were elucidated by spectral analysis. The in vitro cytotoxic activities of the isolated compounds were studied by MTT method. Results: Nine compounds were isolated and identified as ledumone (1), uvaol (2), lepenone (3), α-amyrenone (4), ursolic acid (5), lupeol (6), α-amyrin (7), fern-9(11)-ene-2α,3β-diol (8), and fernenol (9). Conclusion: Compound 1 is new named as ledumone, and compounds 4, 8, and 9 are isolated from Ledum palustre for the first time. Fernane type triterpene 1, 8, and 9 show no significant cytotoxicities against A549 and K562 cells.

Phenolic constituents of Ledum palustre and their anti-oxidant activity / 中草药

To study the chemical constituents of Ledum palustre. Methods Compounds were isolated from n-hexane fraction in the ethanol extract from L. palustre by silica gel column chromatography and HPLC. The structures of the chemical constituents were identified by analysis on their spectral data. Results Fourteen compounds were isolated from EtOAc fraction in the ethanol extract from L. palustre and identified as resveratorol (1), moracin M (2), catechin (3), epicatechin (4), scopoletin (5), esculetin (6), fraxetin (7), 5-hydroxy-2methoxybenzoic acid (8), fraxidin (9), 2α,3α-epoxy-5,7,3’,4’-tetrahydroxyflavan-(4β-8)-epicatechin (10), 2α,3α-epoxy-5,7,3’,4’-tetrahydroxyflavan-(4β-8-catechin) (11), cleomiscosin A (12), cleomiscosin C (13), and isofraxoside (14). Conclusion Compounds 1, 2, and 8-13 are obtained from the plants of Ledum L. for the first time. Compounds 3, 4, 6, 7, 10, and 11 had significant anti-oxidative activities.

Chemical constituents of Ledum palustre (I) / 中草药

Objective: To study the chemical constituents of Ledum palustre. Methods: Compounds were isolated from n-hexane fraction in the ethanol extract from L. palustre by silica gel column chromatography and HPLC. The structures of the chemical constituents were identified by analysis on their spectral data. Results: Thirteen compounds were isolated from n-hexane fraction in the ethanol extract from L. palustre and identified as euphol acetate (1), lanosta-8, 24-dien-3-one (2), taraxerol (3), labda-8(17), 14-dien-13-ol (4), (24S)-stigmast-4-en-3-one (5), euphol (6), isopimaric acid (7), larixyl acetate (8), 28-hydroxyl-lupenone (9), β-sitosterol (10), isocalamendiol (11), erythrodiol (12), and uvaol (13). Conclusion: Compounds 2, 4-9, 11, and 12 are first obtained from the plants of Ledum L.