Ten undescribed cadinane-type sesquiterpenoids from Eupatorium chinense.

Ten undescribed cadinane-type sesquiterpenes (1-10) were isolated from the whole plant of Eupatorium chinense. Their planar structures were mainly elucidated by extensive analysis of spectroscopic data and DFT NMR calculations. The absolute configurations of 1, 2, and 3 were determined by TDDFT ECD calculations while those of compounds 4-7 and 9 were confirmed by single crystal X-ray diffraction experiments. Compounds 2 and 3 are a pair of C-10 epimers, compounds 4 and 5 a pair of C-1 epimers, and compounds 9 and 10 a pair of compounds isomerized at both C-1 and C-10. A possible biosynthetic pathway for these new sesquiterpenes was proposed.

Germacrane sesquiterpenes from leaves of Eupatorium chinense inhibit protein tyrosine phosphatase.

Three new germacrane-type sesquiterpene lactones (1-3) were isolated alongside seven known related congeners (4-10) from the leaves of Eupatorium chinense L. (Compositae). The planar structures of 1-3 were elucidated by their spectroscopic data, including 1D and 2D NMR spectra. The relative and absolute configurations of 1-3 were determined using NOESY experiments and electronic circular dichroism analyses. Compounds 1, 4, 5, and 7 inhibited protein tyrosine phosphatase (PTP) 1B activity with IC50 values of 25, 11, 28, and 24 µM, respectively. Among these, compound 4 exhibited an inhibitory effect on T-cell PTP (TCPTP) with an IC50 value of 25 µM. To our knowledge, this is the first study demonstrating the PTP inhibitory activity of the germacrane sesquiterpenes. The results show that compound 4 acts as an inhibitor of both PTP1B and TCPTP.

Alkyl-benzofuran dimers from Eupatorium chinense with insulin-sensitizing and anti-inflammatory activities.

Five new racemic alkyl-benzofuran dimers, (±)-dieupachinins I-M (1-5), were isolated from the root tubers of Eupatorium chinense, a well-known traditional Chinese medicine for the treatment of diphtheria in Guangdong province. The structures of these compounds, especially the first examples of 12,10'-epoxy dimer dieupachinin I (1), 12-nor-dimer dieupachinin J (2), and 12,12'-dinor-dimer dieupachinin K (3), were elucidated by spectroscopic data analysis. Chiral resolution were further carried out on a cellulose column by HPLC, and compounds 2-5 were successfully separated into two enantiomers, respectively. The absolute configurations of (+)-(2-5) and (-)-(2-5) were established by theoretical ECD calculation. All the compounds were evaluated for insulin-stimulated glucose uptake in C2C12 myotubes and (±)-dieupachinin I (1) exhibited the best activity. Compound 1 enhanced insulin-stimulated glucose uptake via activating the insulin receptor substrate 1/protein kinase B/glycogen synthase kinase-3ß signaling pathway. Moreover, all the isolates were tested for their nitric oxygen (NO) inhibitory effects in lipopolysaccharide-treated RAW264.7 macrophages, and compounds (±)-1, (±)-2, and (±)-4 showed promising inhibitory effects with IC50 values of 6.42 ± 1.85, 6.29 ± 1.94, and 16.03 ± 2.07 µM, respectively. (±)-Dieupachinin I (1) again dose-dependently suppressed LPS-induced expression of inducible NO synthase and nuclear translocation of p65.

Seven new chemical constituents from the underground parts of Eupatorium chinense.

Three new sesquiterpenoids (1-3) and four new benzofuran dimers (+)-4 and (-)-4, (+)-5 and (-)-5, and four known benzofuran dimers (+)-6 and (-)-6, (+)-7 and (-)-7 were isolated from the underground parts of Eupatorium chinense. The enantiomers of racemates (±)-4 ~ (±)-7 were separated by chiral HPLC columns, and their absolute configurations were determined by circular dichroism experiments. The structures of all new compounds were elucidated on the basis of their NMR, and MS data as well as by comparison with literature values. The all of the isolated compounds were tested in vitro for their cytotoxic activities against the Caski, MDA-MB-231 and HepG2 cancer cell lines.

Targeting pharmacophore with probe-reactivity-guided fractionation to precisely identify electrophilic sesquiterpenes and its activity of anti-TNBC.

INTRODUCTION: Innovative strategy is urgently needed to precisely discover novel natural products as lead compounds for development of new drugs against orphan diseases such as triple-negative breast cancer (TNBC). Herein, we describe a targeting pharmacophore with probe-reactivity-guided strategy for the discovery of electrophilic sesquiterpene (ES), a class of bioactive natural product. OBJECTIVE: This study aimed to identify pharmacophore, based on pharmacophore with probe-reactivity-guided strategy for precisely discovering ESs from ethyl acetate extract of Eupatorium chinense L. (EEEChL) METHODOLOGY: MTT assay combined with ultra-performance liquid chromatography (UPLC) analysis was used to identify pharmacophore. UPLC-mass spectrometry (MS) was applied to carefully compare the intrinsic reactivity characteristics of two chemoselective nucleophilic probes: glutathione (GSH) and 4-bromothiophenol (BTP) reaction with ESs. ESs was isolated and identified from EEEChL by phytochemical methods. Furthermore, stoichiometric ratio and binding site of one typical ES 8ß-[4'-hydroxytigloyloxy]-5-desoxy-8-desacyleuparotin (HDDE) reaction with BTP were studied by UPLC-quadrupole time-of-flight (Q-TOF)-MS and two-dimensional nuclear magnetic resonance (NMR). RESULTS: Eleven ESs were identified from EEEChL, MTT assay illustrated that all of the 11 ESs possess fairly good anti-TNBC activity CONCLUSIONS: Electrophilic groups were confirmed as pharmacophore of bioactive compounds contained in EEEChL. An optimised halogenated aromatic probe BTP furnishes ES-BTP conjugates that are highly conspicuous via MS by virtue of a unique isotopic bromine signature, conjugates also have a considerable separation on C18 column. The new probe-reactivity-guided strategy can effectively improve the traditional bioassay-guided approaches, and significantly increase the probability of obtaining designated bioactive compounds.

Benzofurans from Eupatorium chinense enhance insulin-stimulated glucose uptake in C2C12 myotubes and suppress inflammatory response in RAW264.7 macrophages.

Fourteen acetylbenzofuran derivatives, including three undescribed carbon skeletons with a newly formed hexane or benzene ring on the other side of the benzofuran ring, (±)-eupatonin A (1), (±)-eupatonin B (2), and eupatonin C (3), two new benzofurans (-)-12ß-hydroxygynunone (4) and (+)-12-hydroxyl-13-noreuparin (5), as well as 9 known ones (6-14), were isolated from 95% ethanol extract of the roots of Eupatorium chinense. Their structures were determined by spectroscopic methods and quantum chemical DFT and TDDFT calculations of the NMR chemical shifts and ECD spectra, which helped in the determination of the relative configurations of 1 and 2 and the absolute configurations of 4 and 5, respectively. 1 and 2 were further identified to be racemic mixtures by chiral HPLC analysis. All compounds were evaluated for insulin-stimulated glucose uptake in differentiated C2C12 myotubes. Compounds 1, 3, 4, 5, 11, 12, and 13 markedly enhanced insulin-mediated glucose uptake. (±)-Eupatonin A (1) activated the IRS-1/Akt/GSK-3ß signaling pathway and enhanced insulin stimulated GLUT4 membrane translocation in C2C12 myotubes. On LPS stimulated RAW264.7 macrophages, several compounds exhibited significant inhibitory effect on NO production with IC50 values ranging from 4.94 to 9.70 µΜ. (±)-Eupatonin A (1) again dose-dependently suppressed LPS-induced NO production and decreased the expression of inducible NO synthase (iNOS), through inhibiting NF-κB activity.

Chemical constituents from roots of Eupatorium chinense / 中草药

Objective To study chemical constituents of the roots of Eupatorium chinense. Methods The chemical constituents were separated and purified by the normal phase silica gel column chromatography, preparative thin-layer chromatography, and preparative HPLC. Their structures were determined by various spectral data. Results Nineteen compounds were isolated from the acetic ether extract of E. chinense and the structures were identified as euparin (1), 1-[2-(1-acetoxymethyl-vinyl)-6-hydroxy-benzofuran-5-yl]- ethanone (2), 6-hydroxy-3β-methoxytrematone (3), euparone (4), 8-methoxy-9-hydroxythymol (5), dehydroespeleton (6), 8-methoxy-9-hydroxythymol 3-O-angelate (7), 9-hydroxythymol (8), 4-hydroxy cinnamic acid methyl ester (9), p-hydroxy benzaldehyde (10), 8,9-dehydro-10-hydroxythymol (11), diisobutyl phthalate (12), dibutyl phthalate (13), p-coumaric acid (14), dihydrocoumarin (15), methylcaffeate (16), 2,5-dimethylphenol (17), 1H-indazole (18), and (Z)-3-(hydroxymethyl)-7-methylocta- 2,6-dienly1 acetate (19). Conclusion The chemical constituents are investigated and identified from the roots of E. chinense for the first time. Among them, compounds 2, 3, 5-11 are isolated from E. chinense for the first time, and compounds 6, 9, 12, 14-19 are isolated from the genus of Eupatorium for the first time. Compounds 1-4 are benzofurans, which are the characteristic constituents in Eupatorium genus.

Antiviral benzofurans from Eupatorium chinense.

Eleven benzofuran dimers, (+)-dieupachinins A-E, (-)-dieupachinins A-E and dieupachinin F, a benzofuran trimer trieupachinin A, as well as seven known compounds were isolated from the roots of Eupatorium chinense. The enantiomers of racemates dieupachinins A-E were separated by chiral HPLC. The structures with absolute configurations were elucidated on the basis of spectroscopic data, X-ray diffraction analysis, and circular dichroism experiments. The isolated compounds were evaluated for their in vitro antiviral activities against respiratory syncytial virus (RSV).

Antipyretic Effects of Eupatorium chinense and Its Mechanism / 中草药·英文版

Objective: To investigate the antipyretic effect of Eupatorium chinense and its mechanism. Methods: The content of arginine vasopressin (AVP) in ventral septal area (VSA) and blood plasma, and cyclic adenosine monophosphate (cAMP) levels of hypothalamus and blood plasma were determined by enzyme linked immunosorbent assay. Results: The body temperature (Tb) was decreased at 1 h after administration of E. chinense (3 and 6 g/kg) and Aspirin (0.3 g/kg) respectively, which was significantly different from the temperature of fever model group. The antipyretic effect of Aspirin and E. chinense lasted for longer time. Aspirin (0.3 g/kg) and E. chinense (3 and 6 g/kg) reduced the level of cAMP in hypothalamus of fever rats and increased AVP content in plasma. The changes in cAMP content in plasma of all drug treatment groups were not obvious. Conclusion: E. chinense has strong antipyretic effect and may affect the production of AVP and cAMP in fever rats.

Study on the Flavonoids in She Medicine Eupatorium chinense / 中国药房

OBJECTIVE:To study the flavonoids in She medicine Eupatorium chinense. METHODS:Silica gel,ODS and Sep-hadex LH-20 column chromatography were conducted to isolate and purify the flavonoids in She medicine E. chinense,and com-pound structures were analyzed and identified based on the physicochemical properties and spectral data. RESULTS:From the ethyl acetate extract of E. chinense,10 flavonoids were isolated as tricin (1),quercetin(2),kaempferol(3),luteolin(4),luteo-lin-7-O-β-D-glucoside (5),4-methoxyctricin (6),quercetin-3-O-β-D-glucoside(7),kaempferol-3-O-β-D-glucoside(8),kaempfer-ol-3-O-rutinoside(9)and rutin(10). CONCLUSIONS:Compound 1-10 are isolated from E. chinense for the first time. The study provides certain basis for the quality evaluation of E. chinense.

Fingerprint of Eupatorium chinense by HPLC / 中草药

Objective To establish the HPLC fingerprint of Eupatorium chinense.Methods The ana-lysis was performed on a Kromasil C18 column(250 mm?4.6 mm,5 ?m) with acetonitrile-water as mobile phase in a gradient mode.The flow rate was 1.0 mL/min.The column temperature was 25 ℃ and the detection wavelength was 230 nm.Results The fingerprint of E.chinense with common 13 peaks was established.The relative retention time and the ranges of relative area of the common peaks were determined.Conclusion The established fingerprint could be used for the quality control of E.chinense.

Effects of virus infection on demographic traits of an agamospermous population of Eupatorium chinense (Asteraceae).

There are few studies of the interaction between wild plants and viruses. In this paper, the incidence of a geminivirus (tobacco leaf curl virus, TLCV) infection, and its effects on mortality, growth and reproduction of its host-plant, Eupatorium chinense, are reported. A total of 221 plants of an agamospermous population of E. chinense were chosen and their demographic behaviour followed over 2 years (1991-1992). The proportion of infected plants differed between years, with fewer plants infected in 1991 than in 1992. Under low virus incidence (35.3% in 1991), infection was significantly associated with taller plants (>80 cm). However, when the incidence of infected plants increased by almost two times (69.1%) in 1992, this tendency disappeared and small plants were also infected. Virus infection had significant effects on mortality of agamospermous plants. Almost half of the initial number of marked plants (n=221) died after 1 year of observations. Of those dead plants (n=105), 86 plants (82%) were infected in 1991, indicating that virus infection was an important, but not the sole cause of mortality. In 1992, 116 plants were alive, and of these, 40% were infected in 1991, indicating that some infected plants survived 1 year. Agamospermous plants were classified in three groups according to the extent of virus infection (plants infected in 2 years, infected in 1 year and uninfected plants) to detect the effect of virus infection on growth of plants of E. chinense. Infected plants had significantly lower growth rates than healthy plants. Infected plants also produced significantly fewer seeds than uninfected plants. Virus infection, however, had no significant effect on the probability of reproduction in plants of E. chinense, suggesting that infected plants may reproduce but with a lower seed output. In this study, we showed that virus infection may have a strong effect on demographic traits and, as a consequence, on fitness components of plants of E. chinense. These effects were higher than those sometimes observed in other plant-herbivore or plant-pathogen interactions.