A new flavan named 4α; 5-dimethoxy-8-formyl-7-hydroxy-6-methylflavan （1） was isolated from Sinacalia tangutica. Its structure was determined using spectroscopic methods and X-ray diffraction experiments.
Two new compounds 7-hydroxy-5-O-（β-D-glucopyranoside） flavan （1） and （Z）-4＇,6＇-dihydroxy-2＇-O-（β-D-glucopyranoside） chalcone （2）, along with eight known compounds, were isolated from the stem bark of Dr...Two new compounds 7-hydroxy-5-O-（β-D-glucopyranoside） flavan （1） and （Z）-4＇,6＇-dihydroxy-2＇-O-（β-D-glucopyranoside） chalcone （2）, along with eight known compounds, were isolated from the stem bark of Drypetes parvifolia （Euphorbiaceae）. Their structures were established on the basis of spectroscopic analysis and chemical evidence.展开更多
Objective Flavans are a set of naturally occurring flavonoids possessing a 2-phenylchroman nucleus,which are widely distributed in the plant kingdom.A number of flavan compounds exhibit antitumor activities.In our pre...Objective Flavans are a set of naturally occurring flavonoids possessing a 2-phenylchroman nucleus,which are widely distributed in the plant kingdom.A number of flavan compounds exhibit antitumor activities.In our previous report,a straightforward synthetic procedure for 2(±)-7,8,3',4',5'-pentamethoxyflavan(PMF)was developed.To be more important,PMF showed growth inhibitory effect on various human tumor cell lines,especially against HL60 cells.In the present study,we aim to investigate the molecular mechanisms of action of PMF in HL60 cells.This is the first report of the molecular mechanisms on anti-tumor effect of flavan compounds.Methods Trypan blue exclusion experiment was used for cell growth inhibition assay.Cell apoptosis,cell cycle distribution and the mitochondrial membrane potential(MMP)were assessed by flowcytometric analysis after AO/EB,PI and Rh123 flurescence staining,respectively.Cell cycle-and apoptosis-related proteins were detected using western blotting analysis.Results PMF(1-30 μM)inhibited the growth of HL60 cells in a time-and concentration-dependent manner.Antiproliferative effect of PMF on HL60 cells was associated with G2/M cell cycle arrest,which was mediated by regulating the expression of p21,Cdc25C and cyclin A proteins and inhibiting the phosphorylation of Cdc2 at Thr161.The prolonged PMF treatment also induced apoptosis of HL60 cells,which was characterized by DNA fragmentation,cleavage of poly(ADP-ribose)polymerase,caspase-3,caspase-8 and caspase-9,changes of Bcl-2 and Bax expression and a decrease in the mitochondrial membrane potential(MMP).Furthermore,caspase-3 inhibitor,not caspase-8 inhibitor and caspase-9 inhibitor,completely blocked PMF-caused apoptosis.Conclusions PMF inhibited the growth of HL60 cells via induction of G2/M arrest and apoptosis.Blockade of cell cycle was associated with the downregulation of Cdc2 complex activity.Both death receptor and mitochondrial apoptotic pathways explained PMF-caused apoptosis.展开更多
A novel phenylpropanoid-substituted catechin glycoside glabraoside A 1 and a new dihydrochalcone 3＇-（7＂-allylphenyl）-2＇,4＇,4＂-trihydroxy-6＇-methoxydihydrochalcone 2 were isolated from the herbs of Sarcandra gl...A novel phenylpropanoid-substituted catechin glycoside glabraoside A 1 and a new dihydrochalcone 3＇-（7＂-allylphenyl）-2＇,4＇,4＂-trihydroxy-6＇-methoxydihydrochalcone 2 were isolated from the herbs of Sarcandra glabra. Their structures were elucidated on the basis of spectroscopic analyses and chiroptical methods.展开更多
Objective To study the chemical constituents of Pronephrium triphyllum.Methods The chemical constituents in the plant were isolated and purified with silica gel and Sephadex LH-20.Their structures were identified by a...Objective To study the chemical constituents of Pronephrium triphyllum.Methods The chemical constituents in the plant were isolated and purified with silica gel and Sephadex LH-20.Their structures were identified by analyses of spectral data and physicochemical properties.Results Six compounds were isolated and identified as shelincaoide A(1),n-butyl-β-D-fructopyranoside(2),triphyllin A(3),6,7-di-hydroxycoumarin(4),daucosterol(5),and β-sitosterol(6),respectively.Conclusion Compound 1 is found to be a new compound.Compounds 2 and 4 are firstly isolated from the plants in Pronephrium Presl.and all compounds except 3 are obtained from the species for the first time.展开更多
文摘A new flavan named 4α; 5-dimethoxy-8-formyl-7-hydroxy-6-methylflavan （1） was isolated from Sinacalia tangutica. Its structure was determined using spectroscopic methods and X-ray diffraction experiments.
基金One of the authors(J.Wandji)is grateful for grant(No.F/2624-3F)from the International Foundation for Science(Sweden)the sponsorship of the"UniversitéParis Descartes,France"during his multiple research visits in Paris.
文摘Two new compounds 7-hydroxy-5-O-（β-D-glucopyranoside） flavan （1） and （Z）-4＇,6＇-dihydroxy-2＇-O-（β-D-glucopyranoside） chalcone （2）, along with eight known compounds, were isolated from the stem bark of Drypetes parvifolia （Euphorbiaceae）. Their structures were established on the basis of spectroscopic analysis and chemical evidence.
文摘Objective Flavans are a set of naturally occurring flavonoids possessing a 2-phenylchroman nucleus,which are widely distributed in the plant kingdom.A number of flavan compounds exhibit antitumor activities.In our previous report,a straightforward synthetic procedure for 2(±)-7,8,3',4',5'-pentamethoxyflavan(PMF)was developed.To be more important,PMF showed growth inhibitory effect on various human tumor cell lines,especially against HL60 cells.In the present study,we aim to investigate the molecular mechanisms of action of PMF in HL60 cells.This is the first report of the molecular mechanisms on anti-tumor effect of flavan compounds.Methods Trypan blue exclusion experiment was used for cell growth inhibition assay.Cell apoptosis,cell cycle distribution and the mitochondrial membrane potential(MMP)were assessed by flowcytometric analysis after AO/EB,PI and Rh123 flurescence staining,respectively.Cell cycle-and apoptosis-related proteins were detected using western blotting analysis.Results PMF(1-30 μM)inhibited the growth of HL60 cells in a time-and concentration-dependent manner.Antiproliferative effect of PMF on HL60 cells was associated with G2/M cell cycle arrest,which was mediated by regulating the expression of p21,Cdc25C and cyclin A proteins and inhibiting the phosphorylation of Cdc2 at Thr161.The prolonged PMF treatment also induced apoptosis of HL60 cells,which was characterized by DNA fragmentation,cleavage of poly(ADP-ribose)polymerase,caspase-3,caspase-8 and caspase-9,changes of Bcl-2 and Bax expression and a decrease in the mitochondrial membrane potential(MMP).Furthermore,caspase-3 inhibitor,not caspase-8 inhibitor and caspase-9 inhibitor,completely blocked PMF-caused apoptosis.Conclusions PMF inhibited the growth of HL60 cells via induction of G2/M arrest and apoptosis.Blockade of cell cycle was associated with the downregulation of Cdc2 complex activity.Both death receptor and mitochondrial apoptotic pathways explained PMF-caused apoptosis.
基金the National Natural Science Foundation of China （No. 20432030） for financial support.
文摘A novel phenylpropanoid-substituted catechin glycoside glabraoside A 1 and a new dihydrochalcone 3＇-（7＂-allylphenyl）-2＇,4＇,4＂-trihydroxy-6＇-methoxydihydrochalcone 2 were isolated from the herbs of Sarcandra glabra. Their structures were elucidated on the basis of spectroscopic analyses and chiroptical methods.
基金Science and Technology Project of Zhongshan,China (20071A036)
文摘Objective To study the chemical constituents of Pronephrium triphyllum.Methods The chemical constituents in the plant were isolated and purified with silica gel and Sephadex LH-20.Their structures were identified by analyses of spectral data and physicochemical properties.Results Six compounds were isolated and identified as shelincaoide A(1),n-butyl-β-D-fructopyranoside(2),triphyllin A(3),6,7-di-hydroxycoumarin(4),daucosterol(5),and β-sitosterol(6),respectively.Conclusion Compound 1 is found to be a new compound.Compounds 2 and 4 are firstly isolated from the plants in Pronephrium Presl.and all compounds except 3 are obtained from the species for the first time.
