An efficient and feasible synthetic approach was developed for the synthesis of an array of new flavane derivafives from the substituted benzaldehyde with the reduction of chalcones and subsequent cyclization as the k...An efficient and feasible synthetic approach was developed for the synthesis of an array of new flavane derivafives from the substituted benzaldehyde with the reduction of chalcones and subsequent cyclization as the key steps. The purity and structure of the products were confirmed by the elemental analysis and a combination of its IR, ^1H and ^13C NMR, and mass spectra. These synthetic compounds were tested for xanthine oxidase （XO） inhibitions and antifungal actions against Candida albicans, Cryptococcus neoformans, Aspergillus sp. and Trichophyton rubrum. 7-Hydrazinocarbonylmethoxy-4＇-methoxyflavane （9） was found to be the most XO inhibitory with IC50=76.4 μmol/L, and the most potent antifungal compound was 4＇-hydrazinocarbonylmethoxyflavane （12） with minimal inhibition concentration MIC=8 μg/mL against Trichophyton rubrum.展开更多
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.
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 convenient cyclization method for the flavans synthesis is described. BF3 was used for the first time as an efficient catalyst to effect the cyclization of 1,3-diarylpropan-1-ols.
基金Project supported by the Key Project of the Ministry of Education of China （No. 03013）, the National Natural Science Foundation of China （No. 20372010） and Trans-century Training Program Foundation for the Talents, Ministry of Education of China and Chinese Academy of Medical Sciences.
文摘An efficient and feasible synthetic approach was developed for the synthesis of an array of new flavane derivafives from the substituted benzaldehyde with the reduction of chalcones and subsequent cyclization as the key steps. The purity and structure of the products were confirmed by the elemental analysis and a combination of its IR, ^1H and ^13C NMR, and mass spectra. These synthetic compounds were tested for xanthine oxidase （XO） inhibitions and antifungal actions against Candida albicans, Cryptococcus neoformans, Aspergillus sp. and Trichophyton rubrum. 7-Hydrazinocarbonylmethoxy-4＇-methoxyflavane （9） was found to be the most XO inhibitory with IC50=76.4 μmol/L, and the most potent antifungal compound was 4＇-hydrazinocarbonylmethoxyflavane （12） with minimal inhibition concentration MIC=8 μg/mL against Trichophyton rubrum.
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.
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.
文摘A convenient cyclization method for the flavans synthesis is described. BF3 was used for the first time as an efficient catalyst to effect the cyclization of 1,3-diarylpropan-1-ols.
