Chemical constituents of the whole herb of Bidens pilosa L. were investigated. By using various column chromatography （CC） and spectroscopic methods, 13 flavonoids were isolated and identified as follows： 2′-hydro...Chemical constituents of the whole herb of Bidens pilosa L. were investigated. By using various column chromatography （CC） and spectroscopic methods, 13 flavonoids were isolated and identified as follows： 2′-hydroxy-4,4′-dimethoxy-chalcone （1）, isoliquiritigenin （2）, 3,2′,4′-trihydroxy-4-methoxy-chalcone （3）, licochalcone A （4）,4′-O-β-D-glucopyranosyl-2′,3-dihydroxy-4-methoxy-chalcone （5）, butein （6）, apigenin （7）, luteolin （8）, diosmetin （9）, chrysoeriol （10）, 3,5,6,7,3′,4′,5′-heptamethoxyflavone （11）, 7-O-β-D-glucopyranosyt-5,3′dihydroxy-3,6,4′-trimethoxyfiavone （12）, sulfuretin （13）. Compounds 1-5, 9, 11 were obtained from the genus Bidens for the first time.展开更多
Stomach and colorectal cancers are common cancers and leading causes of cancer deaths.Because the alimentary tract can interact directly with dietary components,stomach and colorectal cancer may be closely related to ...Stomach and colorectal cancers are common cancers and leading causes of cancer deaths.Because the alimentary tract can interact directly with dietary components,stomach and colorectal cancer may be closely related to dietary intake.We systematically searched published literature written in English via PubMed by searching for terms related to stomach and colorectal cancer risk and dietary flavonoids up to June 30,2012.Twenty-three studies out of 209 identified articles were finally selected for the analysis.Log point effect estimates and the corresponding standard errors were calculated using covariate-adjusted point effect estimates and 95%CIs from the selected studies.Total dietary flavonoid intake was not associated with a reduced risk of colorectal or stomach cancer [odds ratio(OR)(95%CI) = 1.00(0.90-1.11) and 1.07(0.70-1.61),respectively].Among flavonoid subclasses,the intake of flavonols,flavan-3-ols,anthocyanidins,and proanthocyanidins showed a significant inverse association with colorectal cancer risk [OR(95%CI) = 0.71(0.63-0.81),0.88(0.79-0.97),0.68(0.56-0.82),and 0.72(0.61-0.85),respectively].A significant association was found only between flavonols and stomach cancer risk based on a limited number of selected studies [OR(95%CI) = 0.68(0.46-0.99)].In the summary estimates from casecontrol studies,all flavonoid subclasses except flavones and flavanones were inversely associated with colorectal cancer risk,whereas neither total flavonoids nor any subclasses of flavonoids were associated with colorectal cancer risk in the summary estimates based on the cohort studies.The significant association between flavonoid subclasses and cancer risk might be closely related to bias derived from the case-control design.There was no clear evidence that dietary flavonoids are associated with reduced risk of stomach and colorectal cancer.展开更多
Although there was a strong steric effect,isopentenyl and geranyl moieties were successfully introduced into C3 position in flavone skeleton so as to synthesize the 3-isopentenyl flavone and 3-geranyl flavone under tw...Although there was a strong steric effect,isopentenyl and geranyl moieties were successfully introduced into C3 position in flavone skeleton so as to synthesize the 3-isopentenyl flavone and 3-geranyl flavone under two cyclization conditions（AcOH/HCl and concentrated H 2 SO 4 /MeOH） in this report.It was found that the optimum cyclization conditions for 3-isopentenyl flavone and 3-geranyl flavone were,respectively,AcOH/HCl and H 2 SO 4 /MeOH.Furthermore,the donating electron ability is in the sequence 3-geranyl flavone3-isopentenyl flavone according to the density functional theory（DFT） calculations,suggesting the longer alkyl chain at 3-position would be more favorable for enhancing the donating electron ability.The present synthetic routes might reveal potential applicability in our continued studies on the total syntheses of other natural 3-alkyl flavonoids.展开更多
A new flavone glycoside, 5,8-dihydroxy-4',6,7-trimethoxyflavone 8-O-(-D-glucopyranoside 1, together with three known flavonoids, pedalitin 2, cirsimartin 3 and genkwanin 4, were isolated from the aerial parts of I...A new flavone glycoside, 5,8-dihydroxy-4',6,7-trimethoxyflavone 8-O-(-D-glucopyranoside 1, together with three known flavonoids, pedalitin 2, cirsimartin 3 and genkwanin 4, were isolated from the aerial parts of Isodon enanderianus. Their structures were determined on the basis of spectral data.展开更多
[Objective] The aim was to study the flavonoid content of Fagopyrum megaspartanium leaves by water bath and ultrasonic extractions.[Method] By using water bath extraction and ultrasonic extraction,the total flavonoid ...[Objective] The aim was to study the flavonoid content of Fagopyrum megaspartanium leaves by water bath and ultrasonic extractions.[Method] By using water bath extraction and ultrasonic extraction,the total flavonoid content in buckwheat leaves was measured with UV spectrophotometer.[Result] The optimum wavelength for determination of the content of flavonoid extracted from buckwheat leaves was 420 nm;the content of total flavonoid extracted by ultrasonic extraction and water bath extraction from buckwheat were 5.26% and 5.40% respectively;and the average total flavonoid content by water bath extraction was significantly higher than that by ultrasonic extraction.[Conclusion] The result is significant for the improvement of flavonoid content measurement of buckwheat.展开更多
From the ethanol extract of Selaginella moellendorffii Hieron., a new flavone O-glycoside and three known flavone C-glycosides have been isolated and identified as 5-carboxymethyl-4′-hydroxyflavone-7-O-β-D-glucopyra...From the ethanol extract of Selaginella moellendorffii Hieron., a new flavone O-glycoside and three known flavone C-glycosides have been isolated and identified as 5-carboxymethyl-4′-hydroxyflavone-7-O-β-D-glucopyranoside 1, 6,8-di-C-β-D-glueopyranosylapigenin 2, 6-C-[3-D-glucopyranosyl-8-C-β-D-xylopyranosyl apigenin 3, 6-C-B-D-xylopyranosyl-8-C-β-glucopyranosylapigenin 4, respectively. Their structures were elucidated by spectroscopic methods.展开更多
A new Diels-Alder type adduct mongolicin G （1） and a new flavone 5＇-（1＂, 1＂-dimethylallyl）-5,7,2＇,4＇-tetrahydroxyflavone （2） were isolated from the stem and root bark of Morus mongolica. Their structures we...A new Diels-Alder type adduct mongolicin G （1） and a new flavone 5＇-（1＂, 1＂-dimethylallyl）-5,7,2＇,4＇-tetrahydroxyflavone （2） were isolated from the stem and root bark of Morus mongolica. Their structures were determined by spectroscopic analysis and chiroptical methods.展开更多
Flavonoids are widely used in industry for the prevention of various diseases. In daily life we are directly in touch with flavonoids due to their presence in different beverages, fruits and vegetables. Flavonoids are...Flavonoids are widely used in industry for the prevention of various diseases. In daily life we are directly in touch with flavonoids due to their presence in different beverages, fruits and vegetables. Flavonoids are mainly used as a coloring agent in plants, antioxidant and nutritional food for human. Flavonoids have explicit role in UV filtration, symbiotic nitrogen fixation and floral pigmentation. Flavonoids have potential for different biological activities like chelation of metals, decreasing platelets aggregation and cell signaling etc.展开更多
The new flavone, 5,4′-dihydroxy-6,7-methylenedioxy-3′-methoxyflavone, and one new isoflavone glycoside, 3′,5′-dimethoxy irisolone-4′-O-β-d-glucoside were isolated from the rhizomes of Belamcanda chinensis. Their...The new flavone, 5,4′-dihydroxy-6,7-methylenedioxy-3′-methoxyflavone, and one new isoflavone glycoside, 3′,5′-dimethoxy irisolone-4′-O-β-d-glucoside were isolated from the rhizomes of Belamcanda chinensis. Their structures were established based on the spectroscopic methods.展开更多
A new flavone, 6, 2-dihydroxy-5, 7, 8, 6-tetramethoxyflavone, was isolated from the roots of Scutellaria baicalensis. Its structure was established on the basis of spectral evidences.
[Objective] The aim was to establish a rapid method for the determination of the content of total flavonoids in the honey comb. [Method] The content of total flavonoids weas determined based on samples including comb ...[Objective] The aim was to establish a rapid method for the determination of the content of total flavonoids in the honey comb. [Method] The content of total flavonoids weas determined based on samples including comb honey, propolis, royal jelly, linden tree honey, with a polyamide column chromatography by spectrophotometry at 360 nm wavelength. [Result] The recovery rate of the method was above 90%, and the variation coefficient was lower than 2%. Compared with the traditional method, this method has less reagent consumption, simple operation and so on.[Conclusion] The content of total flavonoids in comb honey was 14.97 mg/100 g, although is only 0.87% of the total flavone content in propolis. The contained total flavonoids at least doubled than that of others and comb honey is more valuable in the content of flavonoids.展开更多
A new flavone glycoside, named mahuangchiside, was isolated from the root of Chirita fimbrisepala Hand.-Mazz. The structure was elucidated as 5,4'-dihydroxy-6-methoxyflavone-7-O-beta-D-xylopyranosyl(1-->2)-beta...A new flavone glycoside, named mahuangchiside, was isolated from the root of Chirita fimbrisepala Hand.-Mazz. The structure was elucidated as 5,4'-dihydroxy-6-methoxyflavone-7-O-beta-D-xylopyranosyl(1-->2)-beta-D-xylopyranoside on the basis of spectral analysis (H-1-H-1 COSY. C-13-H-1 HETCOR and HMBC) and chemical evidence.展开更多
A simple,rapid and sensitive method for the quantification of camellianin B in Cephalotaxus sinensis（C.sinensis）a natural plant with anti-hyperglycemic effect,was developed and validated by reversed phase liquid chr...A simple,rapid and sensitive method for the quantification of camellianin B in Cephalotaxus sinensis（C.sinensis）a natural plant with anti-hyperglycemic effect,was developed and validated by reversed phase liquid chromatography.Chromatographic separation was achieved on a C18 column and an isocratic elution was carried out at a flow-rate of 1.0 mL·min-1 with the acetonitrile-water containing0.1%formic acid（19∶81,v/v）.The detection wavelength was set at 330 nm.The calibration curve was linear over the concentration range of 0.25-50μg·mL-1 with correlation coefficients larger than0.999 5.The limit of detection and limit of quantification were 0.09μg·mL-1and 0.25μg·mL-1,respectively.The precisions and accuracy for all samples were acceptable.The validated method has been successfully applied for the quantification of camellianin B in C.sinensis harvested in different months and may also be used as the quality evaluation of this herb medicine.展开更多
[Objective] The aim was to analyze content of flavones in honey of pomegranate flowers. [Method] Contents of total flavones in 24 honey samples of pomegranate flowers from Mengzi City in 2011 and 2012 were measured as...[Objective] The aim was to analyze content of flavones in honey of pomegranate flowers. [Method] Contents of total flavones in 24 honey samples of pomegranate flowers from Mengzi City in 2011 and 2012 were measured as per- spectrophotometry method with acetone as an extractant and rutin as a control. [Result] The average content of flavones in honey of pomegranate flowers was at （2.36±1.36）mg/100 g in 2011 and significantly higher than that in 2012 at （1.71± 0.53）mg/100 g. Analysis was conducted on flavones content in different batches and the results indicated that content of flavones in honey in different batches changed from increasing to decreasing, namely, the content was maximal in peak flowering stage, followed by late flowering stage and initial flowering stage. [Conclusion] The research provides references for development, use and function exploration of the honey of pomegranate flowers.展开更多
Synthesis of 4'-methoxyflavone, first by the reaction of 4 - methoxy acetophenone enamine with heptanedioyl chloride, then by dehydrogenation, is described.
The title compounds are prepared in good yields by iodination of the corresponding flavones, thioflavones and thiochromones respectively using I_2-CAN(ceric ammonium nitrate) system. The compounds thus prepared are po...The title compounds are prepared in good yields by iodination of the corresponding flavones, thioflavones and thiochromones respectively using I_2-CAN(ceric ammonium nitrate) system. The compounds thus prepared are potentially useful precursors for the synthesis of C-3 linked binuclear compounds.展开更多
The enthalpies of bond dissociations of the hydroxyl groups, the energy of the highest occupied molecular orbitals and the corresponding radicals spin densities of all possible ten isomeric mono-hydroxyl flavones are ...The enthalpies of bond dissociations of the hydroxyl groups, the energy of the highest occupied molecular orbitals and the corresponding radicals spin densities of all possible ten isomeric mono-hydroxyl flavones are calculated by means of 3-parameter Becke, Lee, Yang and Parr functional. The structural factors affecting these descriptors of radical-scavenging activity are outlined. The results obtained show that the hydroxyl groups in ring A and C are more involved in the process of a radical-capturing than recently believed.展开更多
Two novel flavone glycosides, 3′_hydroxy_5,4′_dimethoxy_6,7_methylenedioxyflavone_3_O_[β_D_xylopyranosyl(1→6)]_β_D_glucopyranoside (1) and 5,4′_dimethoxy_3′_isopropenylacetyl_6,7_methylenedioxyflavone_3_O_[β_D...Two novel flavone glycosides, 3′_hydroxy_5,4′_dimethoxy_6,7_methylenedioxyflavone_3_O_[β_D_xylopyranosyl(1→6)]_β_D_glucopyranoside (1) and 5,4′_dimethoxy_3′_isopropenylacetyl_6,7_methylenedioxyflavone_3_O_[β_D_xylopyranoxyl(1→6)]_β_D_glucopyranoside (2), were isolated from Polygonum sphaerostachyum Meisn., and their structures were deduced by spectral and chemical methods. This is the first report on the isolation of flavone glycosides from P. sphaerostachyum.展开更多
Genus Codonopsis comprises more than 40 species in China. The roots of these plants have been used as traditional Chinese medicines or folk love herbs. Codonopsis xundianensis Wang ZT et Xu GJ grows in Yunnan Province...Genus Codonopsis comprises more than 40 species in China. The roots of these plants have been used as traditional Chinese medicines or folk love herbs. Codonopsis xundianensis Wang ZT et Xu GJ grows in Yunnan Province and its roots are often used as a tonic. In this paper, we report the isolation and structural elucidation of chrysoeriol (1), tricin (2), wogonin (3) and luteolin (4) from the roots of Codonopsis xundianensis. Compounds 1-3 were found in Codonopsis for the first time.展开更多
A new series of sulfonamide flavone derivatives are designed as non-covalent inhibitors of proteasome assisted with computer-aided drug design （CADD）. The desired compounds were synthesized successfully and the biol...A new series of sulfonamide flavone derivatives are designed as non-covalent inhibitors of proteasome assisted with computer-aided drug design （CADD）. The desired compounds were synthesized successfully and the biological evaluation was subsequently accomplished. The results showed negligible improvement from our lead compound （IC50 for β5 subunit was 14.0 μM）. Thus, these flavone derivatives might be improved as potential 20S proteasome inhibitors.展开更多
基金Research Platform for Quality Standard of TCM and Information System Building(Grant No.2009ZX09308-04)National S&T Major Project-Created Major New Drugs Projects (Grant No.2009ZX09311-004)
文摘Chemical constituents of the whole herb of Bidens pilosa L. were investigated. By using various column chromatography （CC） and spectroscopic methods, 13 flavonoids were isolated and identified as follows： 2′-hydroxy-4,4′-dimethoxy-chalcone （1）, isoliquiritigenin （2）, 3,2′,4′-trihydroxy-4-methoxy-chalcone （3）, licochalcone A （4）,4′-O-β-D-glucopyranosyl-2′,3-dihydroxy-4-methoxy-chalcone （5）, butein （6）, apigenin （7）, luteolin （8）, diosmetin （9）, chrysoeriol （10）, 3,5,6,7,3′,4′,5′-heptamethoxyflavone （11）, 7-O-β-D-glucopyranosyt-5,3′dihydroxy-3,6,4′-trimethoxyfiavone （12）, sulfuretin （13）. Compounds 1-5, 9, 11 were obtained from the genus Bidens for the first time.
文摘Stomach and colorectal cancers are common cancers and leading causes of cancer deaths.Because the alimentary tract can interact directly with dietary components,stomach and colorectal cancer may be closely related to dietary intake.We systematically searched published literature written in English via PubMed by searching for terms related to stomach and colorectal cancer risk and dietary flavonoids up to June 30,2012.Twenty-three studies out of 209 identified articles were finally selected for the analysis.Log point effect estimates and the corresponding standard errors were calculated using covariate-adjusted point effect estimates and 95%CIs from the selected studies.Total dietary flavonoid intake was not associated with a reduced risk of colorectal or stomach cancer [odds ratio(OR)(95%CI) = 1.00(0.90-1.11) and 1.07(0.70-1.61),respectively].Among flavonoid subclasses,the intake of flavonols,flavan-3-ols,anthocyanidins,and proanthocyanidins showed a significant inverse association with colorectal cancer risk [OR(95%CI) = 0.71(0.63-0.81),0.88(0.79-0.97),0.68(0.56-0.82),and 0.72(0.61-0.85),respectively].A significant association was found only between flavonols and stomach cancer risk based on a limited number of selected studies [OR(95%CI) = 0.68(0.46-0.99)].In the summary estimates from casecontrol studies,all flavonoid subclasses except flavones and flavanones were inversely associated with colorectal cancer risk,whereas neither total flavonoids nor any subclasses of flavonoids were associated with colorectal cancer risk in the summary estimates based on the cohort studies.The significant association between flavonoid subclasses and cancer risk might be closely related to bias derived from the case-control design.There was no clear evidence that dietary flavonoids are associated with reduced risk of stomach and colorectal cancer.
基金Supported by the National Natural Science Foundation of China(No.20062001)the Natural Science Foundation of Guangxi Zhuang Autonomous Region,China(Nos.0991009 and 0447036)
文摘Although there was a strong steric effect,isopentenyl and geranyl moieties were successfully introduced into C3 position in flavone skeleton so as to synthesize the 3-isopentenyl flavone and 3-geranyl flavone under two cyclization conditions（AcOH/HCl and concentrated H 2 SO 4 /MeOH） in this report.It was found that the optimum cyclization conditions for 3-isopentenyl flavone and 3-geranyl flavone were,respectively,AcOH/HCl and H 2 SO 4 /MeOH.Furthermore,the donating electron ability is in the sequence 3-geranyl flavone3-isopentenyl flavone according to the density functional theory（DFT） calculations,suggesting the longer alkyl chain at 3-position would be more favorable for enhancing the donating electron ability.The present synthetic routes might reveal potential applicability in our continued studies on the total syntheses of other natural 3-alkyl flavonoids.
文摘A new flavone glycoside, 5,8-dihydroxy-4',6,7-trimethoxyflavone 8-O-(-D-glucopyranoside 1, together with three known flavonoids, pedalitin 2, cirsimartin 3 and genkwanin 4, were isolated from the aerial parts of Isodon enanderianus. Their structures were determined on the basis of spectral data.
基金Supported by National Key Technology Research and Development Program(2006BAD02B06)National Natural Science Foundation of China(31060207)+1 种基金Agricultural Research Project of Guizhou Province[NY(2010)3094]Special Program of Plant and Animal Breeding of Guizhou Province[No.(2010)023]~~
文摘[Objective] The aim was to study the flavonoid content of Fagopyrum megaspartanium leaves by water bath and ultrasonic extractions.[Method] By using water bath extraction and ultrasonic extraction,the total flavonoid content in buckwheat leaves was measured with UV spectrophotometer.[Result] The optimum wavelength for determination of the content of flavonoid extracted from buckwheat leaves was 420 nm;the content of total flavonoid extracted by ultrasonic extraction and water bath extraction from buckwheat were 5.26% and 5.40% respectively;and the average total flavonoid content by water bath extraction was significantly higher than that by ultrasonic extraction.[Conclusion] The result is significant for the improvement of flavonoid content measurement of buckwheat.
基金supported by the National Natural Science Foundation of China (No.30470193).
文摘From the ethanol extract of Selaginella moellendorffii Hieron., a new flavone O-glycoside and three known flavone C-glycosides have been isolated and identified as 5-carboxymethyl-4′-hydroxyflavone-7-O-β-D-glucopyranoside 1, 6,8-di-C-β-D-glueopyranosylapigenin 2, 6-C-[3-D-glucopyranosyl-8-C-β-D-xylopyranosyl apigenin 3, 6-C-B-D-xylopyranosyl-8-C-β-glucopyranosylapigenin 4, respectively. Their structures were elucidated by spectroscopic methods.
基金the National Natural Science Foundation of China(NO.20432030)for financial support.
文摘A new Diels-Alder type adduct mongolicin G （1） and a new flavone 5＇-（1＂, 1＂-dimethylallyl）-5,7,2＇,4＇-tetrahydroxyflavone （2） were isolated from the stem and root bark of Morus mongolica. Their structures were determined by spectroscopic analysis and chiroptical methods.
文摘Flavonoids are widely used in industry for the prevention of various diseases. In daily life we are directly in touch with flavonoids due to their presence in different beverages, fruits and vegetables. Flavonoids are mainly used as a coloring agent in plants, antioxidant and nutritional food for human. Flavonoids have explicit role in UV filtration, symbiotic nitrogen fixation and floral pigmentation. Flavonoids have potential for different biological activities like chelation of metals, decreasing platelets aggregation and cell signaling etc.
文摘The new flavone, 5,4′-dihydroxy-6,7-methylenedioxy-3′-methoxyflavone, and one new isoflavone glycoside, 3′,5′-dimethoxy irisolone-4′-O-β-d-glucoside were isolated from the rhizomes of Belamcanda chinensis. Their structures were established based on the spectroscopic methods.
基金This work was support by the National Natural Science Foundation of China.
文摘A new flavone, 6, 2-dihydroxy-5, 7, 8, 6-tetramethoxyflavone, was isolated from the roots of Scutellaria baicalensis. Its structure was established on the basis of spectral evidences.
基金Supported by Guangzhou Municipal Colleges and Universities with Research Base Project in 2014(14CXY07)Institute of Scientific Research Projects in 2014(LK14002)the Transverse Research Project in 2014(w14001)~~
文摘[Objective] The aim was to establish a rapid method for the determination of the content of total flavonoids in the honey comb. [Method] The content of total flavonoids weas determined based on samples including comb honey, propolis, royal jelly, linden tree honey, with a polyamide column chromatography by spectrophotometry at 360 nm wavelength. [Result] The recovery rate of the method was above 90%, and the variation coefficient was lower than 2%. Compared with the traditional method, this method has less reagent consumption, simple operation and so on.[Conclusion] The content of total flavonoids in comb honey was 14.97 mg/100 g, although is only 0.87% of the total flavone content in propolis. The contained total flavonoids at least doubled than that of others and comb honey is more valuable in the content of flavonoids.
文摘A new flavone glycoside, named mahuangchiside, was isolated from the root of Chirita fimbrisepala Hand.-Mazz. The structure was elucidated as 5,4'-dihydroxy-6-methoxyflavone-7-O-beta-D-xylopyranosyl(1-->2)-beta-D-xylopyranoside on the basis of spectral analysis (H-1-H-1 COSY. C-13-H-1 HETCOR and HMBC) and chemical evidence.
基金Supported by the Opening Foundation of the State Key Laboratory of Space Medicine Fundamentals and Application,Chinese Astronaut Research and Training Center(SMFA15K04)
文摘A simple,rapid and sensitive method for the quantification of camellianin B in Cephalotaxus sinensis（C.sinensis）a natural plant with anti-hyperglycemic effect,was developed and validated by reversed phase liquid chromatography.Chromatographic separation was achieved on a C18 column and an isocratic elution was carried out at a flow-rate of 1.0 mL·min-1 with the acetonitrile-water containing0.1%formic acid（19∶81,v/v）.The detection wavelength was set at 330 nm.The calibration curve was linear over the concentration range of 0.25-50μg·mL-1 with correlation coefficients larger than0.999 5.The limit of detection and limit of quantification were 0.09μg·mL-1and 0.25μg·mL-1,respectively.The precisions and accuracy for all samples were acceptable.The validated method has been successfully applied for the quantification of camellianin B in C.sinensis harvested in different months and may also be used as the quality evaluation of this herb medicine.
基金Supported by Youth Entrepreneurship Foundation of Institute of Sericulture and Apiculture,Yunnan Academy of Agricultural Sciences (QC2010002)Special Funds of National Modern Agricultural and bee industry Technology System (CARS-45-SYZ17)Science&Technology Department Project of Yunnan Province (2011BB012)~~
文摘[Objective] The aim was to analyze content of flavones in honey of pomegranate flowers. [Method] Contents of total flavones in 24 honey samples of pomegranate flowers from Mengzi City in 2011 and 2012 were measured as per- spectrophotometry method with acetone as an extractant and rutin as a control. [Result] The average content of flavones in honey of pomegranate flowers was at （2.36±1.36）mg/100 g in 2011 and significantly higher than that in 2012 at （1.71± 0.53）mg/100 g. Analysis was conducted on flavones content in different batches and the results indicated that content of flavones in honey in different batches changed from increasing to decreasing, namely, the content was maximal in peak flowering stage, followed by late flowering stage and initial flowering stage. [Conclusion] The research provides references for development, use and function exploration of the honey of pomegranate flowers.
文摘Synthesis of 4'-methoxyflavone, first by the reaction of 4 - methoxy acetophenone enamine with heptanedioyl chloride, then by dehydrogenation, is described.
文摘The title compounds are prepared in good yields by iodination of the corresponding flavones, thioflavones and thiochromones respectively using I_2-CAN(ceric ammonium nitrate) system. The compounds thus prepared are potentially useful precursors for the synthesis of C-3 linked binuclear compounds.
文摘The enthalpies of bond dissociations of the hydroxyl groups, the energy of the highest occupied molecular orbitals and the corresponding radicals spin densities of all possible ten isomeric mono-hydroxyl flavones are calculated by means of 3-parameter Becke, Lee, Yang and Parr functional. The structural factors affecting these descriptors of radical-scavenging activity are outlined. The results obtained show that the hydroxyl groups in ring A and C are more involved in the process of a radical-capturing than recently believed.
基金The National Natural Science Foundation of China(29572064)
文摘Two novel flavone glycosides, 3′_hydroxy_5,4′_dimethoxy_6,7_methylenedioxyflavone_3_O_[β_D_xylopyranosyl(1→6)]_β_D_glucopyranoside (1) and 5,4′_dimethoxy_3′_isopropenylacetyl_6,7_methylenedioxyflavone_3_O_[β_D_xylopyranoxyl(1→6)]_β_D_glucopyranoside (2), were isolated from Polygonum sphaerostachyum Meisn., and their structures were deduced by spectral and chemical methods. This is the first report on the isolation of flavone glycosides from P. sphaerostachyum.
文摘Genus Codonopsis comprises more than 40 species in China. The roots of these plants have been used as traditional Chinese medicines or folk love herbs. Codonopsis xundianensis Wang ZT et Xu GJ grows in Yunnan Province and its roots are often used as a tonic. In this paper, we report the isolation and structural elucidation of chrysoeriol (1), tricin (2), wogonin (3) and luteolin (4) from the roots of Codonopsis xundianensis. Compounds 1-3 were found in Codonopsis for the first time.
基金The National Natural Science Foundation of China(Grant No.21202003)the National Basic Research Program of China(Grant No.2012CB518000)the Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.20120001110010)
文摘A new series of sulfonamide flavone derivatives are designed as non-covalent inhibitors of proteasome assisted with computer-aided drug design （CADD）. The desired compounds were synthesized successfully and the biological evaluation was subsequently accomplished. The results showed negligible improvement from our lead compound （IC50 for β5 subunit was 14.0 μM）. Thus, these flavone derivatives might be improved as potential 20S proteasome inhibitors.
