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1.
Sesquiterpene Lactone Glycosides from Carpesium macrocephalum   总被引:1,自引:0,他引:1  
Two new sesquiterpene lactone glycosides were isolated from the seeds of Carpesium meacrocephalum. Their structures were elucidated as 2α-O-β-D-glucopyranosy-5α,11αH-eudesma-4(15)-en-12,8β-olide and 2α-O-β-D-glucopyranosy-5αH-eudesma-4(15),11(13)-dien-12,8β-olide by spectral methods (HRMS,1D and 2D NMR).  相似文献   
2.
A new eudesmanolide, 1‐oxo‐11αH‐eudesma‐2,4(14)‐dien‐12,8β‐olide ( 1 ), and four new guaianolides, 9β,10β‐epoxy‐4α‐hydroxy‐1βH,11αH‐guaian‐12,8α‐olide ( 2 ), 9β,10β‐epoxy‐4α‐hydroxy‐1βH,11βH‐guaian‐12,8α‐olide ( 3 ), 4α,9α‐dihydroxy‐1βH,11αH‐guai‐10(14)‐en‐12,8α‐olide ( 4 ), and 4α,9α‐dihydroxy‐1βH,11βH‐guai‐10(14)‐en‐12,8α‐olide ( 5 ), together with one known eudesmanolide and two known germacranolides, were isolated from the whole plants of Carpesium triste. Their structures and relative configurations were elucidated on the basis of spectroscopic methods, including 2D‐NMR techniques.  相似文献   
3.
Five new acyclic 12‐hydroxygeranylgeraniol‐derived diterpenoids, i.e., 1 – 5 , were isolated from the seeds of Carpesium triste. The structures including the absolute configurations of the new compounds were elucidated by spectroscopic methods. All the compounds, except for 2 , were evaluated for their in vitro cytotoxic activity against cultured SMMC‐7721 (human hepatoma), HL‐60 (human promyelocytic leukemia), and L02 (human hepatocyte) cells.  相似文献   
4.
Eight new 11-methoxymethylgermacranolides (1–8) were isolated from the ethanol extract of the whole plant of Carpesium divaricatum. The planar structures and relative configurations of the new compounds were determined by detailed spectroscopic analysis. The absolute configuration of 1 was established by electronic circular dichroism (ECD) spectrum and X-ray crystallographic analysis, and the stereochemistry of the new compounds 2–8 were determined by similar ECD data with 1. The absolute configurations of 5 and 7 were further confirmed by using quantum chemical electronic circular dichroism (ECD) calculations. Compound 4 exhibited weak cytotoxicity against MCF-7 cells. Compound 8 could potently decrease PGE2 productions in LPS-induced RAW 264.7 cells.  相似文献   
5.
A two step synthesis of title isocoumarin isolated from Homalium longifolium and its conversion into corresponding 3,4‐dihydroisocoumarin has been described. 3,4‐Dimethoxybenzoyl chloride on condensation with homophthalic acid afforded 3‐(3′,4′‐dimethoxyphenyl)isocoumarin which was demethylated to furnish the 8‐desoxythunberginol A, whereas its sequential saponification, reduction and demethylation yielded the (±)‐8‐desoxy‐3,4‐dihydrothunberginol A. The synthesized compounds were examined in vitro for antibacterial activity.  相似文献   
6.
Leontopodium longifolium (Compositae) have long been used as folk medicine in China for releasing a cough, expectorant and treatment of bronchitis1,2. The chemical constituents of the Leontopodium longifolium were not reported so far. Here we report the s…  相似文献   
7.
Carpesium divaricatum Sieb. & Zucc., a traditional medicinal plant used as an inflammation-relieving remedy, is a rich source of terpenoids. At least 40 germacrane-type sesquiterpene lactones, representatives of four different structural groups, were isolated from the plant. Cytotoxicity against cancer cells in vitro is the most frequently described biological activity of the compounds. However, little is known about the selectivity of the cytotoxic effect. The anti-inflammatory activity of the germacranolides is also poorly documented. The objective of the present study was to assess the cytotoxic activity of selected C. divaricatum germacranolides-derivatives of 4,5,8,9-tetrahydroxy-3-oxo-germacran-6,12-olide towards cancer and normal cell lines (including cells of different p53 status). Moreover, to assess the anti-inflammatory effect of the compounds, the release of four proinflammatory cytokines/chemokines (IL-1β, IL-8, TNF-α and CCL2) by lipopolysaccharide-stimulated human neutrophils was measured by ELISA. The investigated sesquiterpene lactones demonstrated nonselective activity towards prostate cancer (Du145 and PC3) and normal prostate epithelial cells (PNT2) as well as against melanoma cells (A375 and HTB140) and keratinocytes (HaCaT). Cytotoxic activity against osteosarcoma cells was independent of their p53 status. In sub-cytotoxic concentrations (0.5–2.5 µM) the studied compounds significantly decreased cytokine/chemokine release by lipopolysaccharide-stimulated human leukocytes.  相似文献   
8.
NopreviousworkonthechemicalconstituentsofCarpesiumlipskyi(family:Compositae),usedasfolkmedicine,sinceancienttimes,forrelievin...  相似文献   
9.
Carpesium cernuun L. has long been used as chinese folk medicine for its anti-inflammatory, pain-relief, and detoxication properties1. Up to now, no phytochemical studies of Carpesium cernuun has been carried out. Here we report the structure elucidation of a new eudesmanolide 1 and a new aromatic derivative 2, which were obtained from this plant. Compound 1 was isolated as colorless gum, [(]+128.4 (c 0.43, CHCl3). Its EIMS revealed a molecular ion peak m/z 248. Together with the support …  相似文献   
10.
A new eudesmanoilde was isolated from the aerial parts of Carpesium macrocephalum. Its structure was elucidated as 2α-acetoxy-11αH-eudesma-4-en-12,8β-olide by spectral methods.  相似文献   
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