Pseudotaraxasterol

[Chemical constituents of Eupatorium lindleyanum].[Pubmed:22792793]

Zhongguo Zhong Yao Za Zhi. 2012 Apr;37(7):937-40.

To study chemical constituents of Eupatorium lindleyanum. Ethyl acetate extractive fractions were separated with silica gel and Sephadex LH-20 by column chromatography, and their structures were identified on the basis of spectroscopic analysis and chemical evidence. Sixteen compounds were separated and identified as scopoletin (1), 6, 7-dimethylesculetin (2), nepetin (3), eupatrin (4), luteolin (5), isoquerecitrin (6), jaceosidin (7), quceritin (8), kaempferol (9), rutin (10), cirsiliol (11), taraxasterylacetate (12), pseudotaraxasteryl acetate (13), Pseudotaraxasterol (14), butanoic acid (15) and n-hexadecanoic acid (16). Of them, compounds 1-6 and 11, 13 and 15 were separated from this plant for the first time.

Cytotoxic activity and chemical constituents of Anthemis mirheydari.[Pubmed:26864903]

Pharm Biol. 2016 Oct;54(10):2044-9.

Context The genus Anthemis L. (Asteraceae) comprises about 195 species which are widely used in the pharmaceutical, cosmetic and food industries. Objective Anthemis mirheydari Iranshar, an endemic plant from Iran, was investigated for its cytotoxic properties and chemical constituents. Materials and methods The whole parts of the plant (320 g) were extracted by dichloromethane and methanol for four days, successively. The cytotoxic activity of both dichloromethane and methanol extracts were assayed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide colorimetric methods against three human cancer cell lines including LS180, MCF-7 and MOLT-4. Different concentrations (10-100 mug/mL) of the plant extracts were tested to obtain IC50 values. The dichloromethane extract of A. mirheydari was subjected to silica gel-column and thin layer chromatography for purification of its chemical constituents and the isolated compounds were further tested against MOLT-4 cells. The structures of the pure compounds were elucidated using different spectral data including nuclear magnetic resonance and electron impact mass spectra. Results The IC50 values of the dichloromethane extract were 30.8 +/- 6.7, 25.2 +/- 6.5 and 8.6 +/- 1.1 mug/mL (means +/- standard error) for the above-mentioned cell lines, respectively. Two triterpenoids, taraxasterol (1) and Pseudotaraxasterol (2), one sterol, beta-sitosterol (3) and one coumarin, 7-methoxycoumarin (4) were isolated from the extract. The IC50 of the mixture of compounds 1 and 2 as well as compounds 3 and 4 were higher (>100 muM) than that reported for the dichloromethane extract against MOLT-4 cells. Conclusion The dichloromethane extract was the most active one among the tested material.

Triterpenoids with acetylcholinesterase inhibition from Chuquiraga erinacea D. Don. subsp. erinacea (Asteraceae).[Pubmed:19918718]

Planta Med. 2010 Apr;76(6):607-10.

A bioactivity-guided approach was taken to identify the acetylcholinesterase (AChE) inhibitory agents in the ethanolic extract of Chuquiraga erinacea D. Don. subsp. erinacea leaves using a bioautographic method. This permitted the isolation of the pentacyclic triterpenes calenduladiol (1), faradiol (2), heliantriol B2 (3), lupeol (4), and a mixture of alpha-and beta-amyrin ( 5A and 5B) as active constituents. Pseudotaraxasterol (6) and taraxasterol (7) were also isolated from this extract and showed no activity at the same analytical conditions. Compound 1 showed the highest AChE inhibitory activity with 31.2 % of inhibition at 0.5 mM. Looking forward to improve the water solubility of the active compounds, the sodium sulfate ester of 1 was prepared by reaction with the (CH3)3N.SO3 complex. The semisynthetic derivative disodium calenduladiol disulfate (8) elicited higher AChE inhibition than 1 with 94.1 % of inhibition at 0.5 mM (IC (50) = 0.190 +/- 0.003 mM). Compounds 1, 2, 3, 5, 6, and 7 are reported here for the first time in C. erinacea. This is the first report of AChE inhibition from calenduladiol (1) as well as from a sulfate derived from a natural product.