To search for the protective actions of blumea flavanones (BFs) on hepatocytes and hepatic subcellular organelle against lipid peroxidation, monkey′s hepatocytes were isolated and cultured with or without blumea flav...To search for the protective actions of blumea flavanones (BFs) on hepatocytes and hepatic subcellular organelle against lipid peroxidation, monkey′s hepatocytes were isolated and cultured with or without blumea flavanones, then damaged by FeSO 4 cysteine or CCl 4. The lipid peroxidation (malondialdehyde production) and alteration in hepatocyte membrane (leakage of GPT) were estimated. Hepatic subcellular organelles were also isolated and incubated with or without blumea flavanones, then injured by FeSO 4 ascorbate. The generation of malondialdehyde(MDA) was measured. It was found that BFs 10 and 100 μmol·L 1 inhibited the MDA generation and GPT (glutamic pyruvic transaminase) leakage out of hepatocytes that were induced by CCl 4 or FeSO 4 cysteine. BFs could prevent lipid peroxidation initiated by FeSO 4 ascorbate in subcellular organelle suspension. Among BFs, BF 2 possessed the strongest activity. Conclusion: Blumea flavanones possess antioxidation activities that protect monkey′s hepatocytes and hepatic subcellular organelle against injuries induced by FeSO4 or CCl 4.展开更多
Two new lavandulylated flavanones,（2R, 3R）-8-1avandulyl-2＇-methoxy-5, 7, 4＇-trihydroxyflavanonol （1） and 8-1avandulyl-5,7, 4＇-trihydroxyflavonol （2）,were isolated from the dry roots of S opharaflavescens.Thei...Two new lavandulylated flavanones,（2R, 3R）-8-1avandulyl-2＇-methoxy-5, 7, 4＇-trihydroxyflavanonol （1） and 8-1avandulyl-5,7, 4＇-trihydroxyflavonol （2）,were isolated from the dry roots of S opharaflavescens.Their structures were eiucidated on the basis of spectroscopic data. Compounds 1 and 2 exhibited significant antibacterial activities.展开更多
The influence of different alcohol modifiers in mobile phase on the chiral separation of 4-methoxyl flavanone, 5-methoxyl flavanone and 6-methoxyl flavanone on cellulose tris (3, 5-dimethylphenylcarbamate) (CDMPC) col...The influence of different alcohol modifiers in mobile phase on the chiral separation of 4-methoxyl flavanone, 5-methoxyl flavanone and 6-methoxyl flavanone on cellulose tris (3, 5-dimethylphenylcarbamate) (CDMPC) column was studied and the chiral recognition mechanism was discussed. Using hexane-tert-butanol (1.31 mol L-1) as the mobile phase, those three methoxyl flavanones were excellently separated on CDMPC chiral column.展开更多
In the present study,synthetic chalcones,flavanones and Schiff bases were prepared starting from paraceamol,and evaluated their anticipated anti-inflammatory activity.Chalcones were synthesized by reacting 3-acetyl-4-...In the present study,synthetic chalcones,flavanones and Schiff bases were prepared starting from paraceamol,and evaluated their anticipated anti-inflammatory activity.Chalcones were synthesized by reacting 3-acetyl-4-hydroxy acetanilide and aromatic aldehydes in alcoholic potassium hydroxide(KOH) solution under Claisen-Schmidt condensation conditions.The chalcones were cyclized in the presence of piperidine in isoamyl alcohol to obtain flavonone derivatives.Schiff bases were synthesized by condensing 3-acetyl-4-hydroxy anilines with aromatic aldehydes in the presence of HCl.These Schiff bases were further reacted with other aromatic aldehydes in alcoholic KOH solution.PASS cheminformatics software was used to predict the anti-inflammatory activity of synthesized compounds.PASS software predicted that chalcone-based Schiff bases 6a–d contained structural features that can exhibit anti-inflammatory activity.All the prepared derivatives of acetaminophen exhibited moderate to excellent in vivo anti-inflammatory activity in carrageenan-induced edema in rat paw.All the Schiff bases coupled chalcones showed good anti-inflammatory activity compared with the reference drug,diclofenac.Further evaluation of their therapeutic potential and safety profile is required in the future study.展开更多
Six novel compounds,comprising three quinolones(1a,1b,and 2)and three flavanones(3-5),along with seven known analogs(6-13),were isolated from the 95%EtOH extract of the stems and leaves of Glycosmis craibii var.glabra...Six novel compounds,comprising three quinolones(1a,1b,and 2)and three flavanones(3-5),along with seven known analogs(6-13),were isolated from the 95%EtOH extract of the stems and leaves of Glycosmis craibii var.glabra.The structures of the new compounds were elucidated using HR-ESI-MS,UV,and 1D and 2D nuclear magnetic resonance(NMR)data analysis.The ab-solute configurations were determined through Mosher ester and electronic circular dichroism(ECD)spectral analysis.Compounds 2,6,9,and 10 demonstrated inhibition of nitric oxide(NO)production stimulated by lipopolysaccharide in BV-2 microglial cells,with IC50 values ranging from 13.5 to 20.1 μmol·L^(-1),comparable to the positive control,dexamethasone.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
Syzygium campanulatum Korth is a plant, which is a rich source of secondary metabolites （especially flavanones, chalcone, and triterpenoids）. In our present study, three conventional solvent extraction （CSE） techn...Syzygium campanulatum Korth is a plant, which is a rich source of secondary metabolites （especially flavanones, chalcone, and triterpenoids）. In our present study, three conventional solvent extraction （CSE） techniques and supercritical fluid extraction （SFE） techniques were performed to achieve a maximum recovery of two flavanones, chalcone, and two triterpenoids from S. campanulatum leaves. Furthermore, a Box-Behnken design was constructed for the SFE technique using pressure, temperature, and particle size as independent variables, and yields of crude extract, individual and total secondary metabolites as the dependent variables. In the CSE procedure, twenty extracts were produced using ten different solvents and three techniques （maceration, soxhletion, and reflux）. An enriched extract of five secondary metabolites was collected using n-hexane：methanol （1：1） soxhletion. Using food-grade ethanol as a modifier, the SFE methods produced a higher recovery （25.5%-84.9%） of selected secondary metabo- lites as compared to the CSE techniques （0.92%-66.00%）.展开更多
To identify bioactive compound in pigeon pea leaves (Cajanus cajan) that inhibits Salmonella thypi (S. thypi).MethodsThe leaf sample was powdered and macerated with methanol and fractioned by liquid-liquid extrac...To identify bioactive compound in pigeon pea leaves (Cajanus cajan) that inhibits Salmonella thypi (S. thypi).MethodsThe leaf sample was powdered and macerated with methanol and fractioned by liquid-liquid extraction using ethyl acetate. The fraction was chromatographed and the isolates were identified for major component with liquid chromatography-mass spectrometry and the antibacterial activity was tested against S. thypi by Kirby-Bauer method.ResultsSubfraction 1 from the ethyl acetate fraction formed a yellowish solid with m/z 272, identified as naringenin. The naringenin-rich fraction shows fairly well inhibitory toward S. thypi in comparison with chloramphenicol.ConclusionsNaringenin shows antibacterial activity and can be developed to treat typhoid.展开更多
In this overview,the current knowledge of the constituents of flavonoids isolated from the roots of Sophora flavescens(kushen)is updated.Flavonoids consist of several classes,such as flavanones,flavonols,chalcones,iso...In this overview,the current knowledge of the constituents of flavonoids isolated from the roots of Sophora flavescens(kushen)is updated.Flavonoids consist of several classes,such as flavanones,flavonols,chalcones,isoflavones,biflavonoids,flavanols,and flavones.The most common compounds are kurarinone(KRN),sophoraflavanone G(SFG),2′-methoxykurarinone,kuraridine,isoxanthohumol,and formononetin.KRN and SFG are two major flavanones with more vital anticancer properties than other flavonoids.From the literature,the cytotoxic values of KRN and SFG are variable and depend on the type of cancer cells tested.The anticancer activities of these two flavonoids involve different molecular mechanisms.Clinical trials are needed before anticancer drugs from KRN and SFG can be developed.展开更多
A new flavanone was isolated from the roots of Desmos cochinchinensis Lour Its chemical structure was elucidated by spectral analysis as 7 hydroxy 5 methoxy 8 formyl 6 methylflavanone, named desmosflavanone Ⅱ
The total synthesis of （±）-abyssinoflavanone V was first achieved through C-prenylation, selective protection of phenolic hydroxyl group, aldol condensation, cyclization and deprotection starting from cheap 4-h...The total synthesis of （±）-abyssinoflavanone V was first achieved through C-prenylation, selective protection of phenolic hydroxyl group, aldol condensation, cyclization and deprotection starting from cheap 4-hydroxybenzaldehyde and 2,4,6- trihydroxyacetophenone, with total yield 24%. All structures of new compounds were confirmed by IR, 1^H NMR and MS.展开更多
Flavonoids are important bioactive components in Dendrobium officinale,a medicinal orchid.They are involved in many biological activities,including protecting plants against biotic and abiotic stresses.Research on the...Flavonoids are important bioactive components in Dendrobium officinale,a medicinal orchid.They are involved in many biological activities,including protecting plants against biotic and abiotic stresses.Research on the key genes related to flavonoid biosynthesis in D.officinale is limited.In this study,one of the key flavonoid biosynthesis genes,flavanone 3-hydroxylase(F3H),was characterized from D.officinale.The open reading frame of DoF3H was 1134 bp long and it encoded a 377-amino acid protein.The DoF3H protein showed considerably high homology with F3H proteins from other plant species and shared a common evolutionary ancestor with other F3Hs.DoF3H transcripts were detected in different organs of adult plants and mainly accumulated in flowers,followed by roots,stems and leaves,a pattern that was similar to the content of flavonoids.Recombinant DoF3H protein,which was localized in the cytosol,could convert naringenin to dihydrokaempferol.The mRNA levels of DoF3H were significantly induced by salt and cold stresses.Furthermore,the heterologous expression of DoF3H in Escherichia coli conferred it higher tolerance to salt and cold stresses.These results provide insight into the molecular function of DoF3H in the biosynthesis of flavonoids,and provide a new application for improvement of abiotic tolerance in D.officinale.展开更多
A new flavanone （2S）-5, 7, 2＇, 5＇-tetrahydroxy-flavanone 1 together with a new flavanone glycoside （2S）-5, 7, 2＇, 5＇-tetrahydroxy-flavanone 7-O-13-D-glucopyranoside 2, were isolated from the dry roots of Scute...A new flavanone （2S）-5, 7, 2＇, 5＇-tetrahydroxy-flavanone 1 together with a new flavanone glycoside （2S）-5, 7, 2＇, 5＇-tetrahydroxy-flavanone 7-O-13-D-glucopyranoside 2, were isolated from the dry roots of Scutellaria baicalensis. Their structures were elucidated on the basis of spectroscopic data.展开更多
A facile approach for the first total synthesis of two naturally occurring geranylated flavonoids,（±）-puyanin 1 and（±）-4＇-O- methylbonannione 2 has been obtained with total yield 27%and 21%,respectively...A facile approach for the first total synthesis of two naturally occurring geranylated flavonoids,（±）-puyanin 1 and（±）-4＇-O- methylbonannione 2 has been obtained with total yield 27%and 21%,respectively.The key steps were regioselective cyclization of geranylated trihydroxychalcone and regioselective geranylation of 2,4,6-trihydroxyacetophenone.展开更多
The title compound of sakuranetin, a main active flavanone component, was first isolated from Populus tomentosa Carr. and characterized by X-ray single-crystal diffraction analysis It crystallizes in the monoclinic la...The title compound of sakuranetin, a main active flavanone component, was first isolated from Populus tomentosa Carr. and characterized by X-ray single-crystal diffraction analysis It crystallizes in the monoclinic lattice, space group P21/c with a = 12.8531（12）, b = 5.7141（3）, c = 18.0355（12） A, β = 97.333（8）°, V = 1313.77（16） A^3, Z= 4, Mr = 286.27, C16H14O5,μ（MoKa） = 0.108 mm^-1, Dc = 1.447 g/cm^3, F（000） = 600, the final R = 0.0350 and wR = 0.0859 for 2571 independent reflections （Rint = 0.0246） which were used in all calculations. The molecular crystal structure of sakuranetin shows relative stereochemistry of 5,4′-dihydroxy-7-methoxyflavanone. Intermolecular hydrogen bonds together with the continuous π-π interactions construct the three-dimensional architecture of the title compound. The preliminary bioassay reveals that the title compound exhibits moderate anti-inflammatory activity in vitro against the nitric oxide release.展开更多
Benzyl and anthracenemethyl groups were respectively bonded to the N atoms of 3-aminopropyl functionalized mesoporous SBA-15（APS-SBA-15） to obtain two new base catalysts over which the condensation reaction of benza...Benzyl and anthracenemethyl groups were respectively bonded to the N atoms of 3-aminopropyl functionalized mesoporous SBA-15（APS-SBA-15） to obtain two new base catalysts over which the condensation reaction of benzaldehyde and 2＇-hydroxyacetophenone was studied.Good catalytic activities and high selectivities for flavanones were obtained in solvent-free reactions,which is attributed to the effect of benzyl and anthracenemetyl groups on the base sites of catalysts and the steric hindrance of futher reaction of flavanone with benzaldehyde.展开更多
Using naturally colored cotton(NCC)can eliminate dyeing,printing and industrial processing,and reduce sewage discharge and energy consumption.Proanthocyanidins(PAs),the primary coloration components in brown fibers,ar...Using naturally colored cotton(NCC)can eliminate dyeing,printing and industrial processing,and reduce sewage discharge and energy consumption.Proanthocyanidins(PAs),the primary coloration components in brown fibers,are polyphenols formed by oligomers or polymers of flavan-3-ol units derived from anthocyanidins.Three essential structural genes for flavanone and flavonoid hydroxylation encoding flavanone-3-hydroxylase(F3H),flavonoid 3’-hydroxylase(F3’H)and flavonoid 3’5’-hydroxylase(F3’5’H)are initially committed in the flavonoid biosynthesis pathway to produce common precursors.The three genes were all expressed predominantly in developing fibers of NCCs,and their expression patterns varied temporally and spatially among NCC varieties.In GhF3Hi,GhF3’Hi and GhF3’5’Hi silenced lines of NCC varieties XC20 and ZX1,the expression level of the three genes decreased in developing cotton fiber,negatively correlated with anthocyanidin content and fiber color depth.Fiber color depth and type in RNAi lines changed with endogenous gene silencing efficiency and expression pattern,the three hydroxylase genes functioned in fiber color formation.GhF3H showed functional differentiation among NCC varieties and GhF3’H acted in the accumulation of anthocyanin in fiber.Compared with GhF3’H,GhF3’5’H was expressed more highly in brown fiber with a longer duration of expression and caused lighter color of fibers in GhF3’5’H silenced lines.These three genes regulating fiber color depth and type could be used to improve these traits by genetic manipulation.展开更多
A series of new flavanone derivatives of farrerol was designed and synthesized as a potent inhibitor of vascular smooth muscle cells（VSMCs） vegetation according to a convenient method. The structures of all the synt...A series of new flavanone derivatives of farrerol was designed and synthesized as a potent inhibitor of vascular smooth muscle cells（VSMCs） vegetation according to a convenient method. The structures of all the synthesized compounds were confirmed by 1H NMR, 13C NMR and EIHR-MS. The biological activities of these compounds against VSMCs in vitro were evaluated. The assay results indicate that two compounds, 5,7-dihydroxy-6,8-dimethyl- 2-（2-nitrophenyl）chroman-4-one（7f） and 2,3-dibromo-4,5-dihydroxydiphenylmethanone（7j） exhibited high activity against VSMCs in vitro with IC50 values of 9.9 and 6.7 μmol/L, respectively, and the preliminary structure-activity relationship（SAR） was described.展开更多
A facile approach for the first total synthesis of naturally occurring geranylated flavanoids sepicanin A has been obtained with total yield 16%starting from 2,4,6-trihydroxyacetophenone after four steps.The key step ...A facile approach for the first total synthesis of naturally occurring geranylated flavanoids sepicanin A has been obtained with total yield 16%starting from 2,4,6-trihydroxyacetophenone after four steps.The key step was the protic acids（HCl or p-TsOH）-catalyzed benzopyrone formation in a protic polar solvent by deprotection and cycUzation of chalcone in one step.展开更多
Two new flavanone glycosides 1 and 2 were isolated from the aerial parts of Macrothelypteris torresiana （Gaud.） Ching. The structures of two products were identified as （2S）-5,7,2＇,5＇-tetrahydroxyflavanone-2＇-O...Two new flavanone glycosides 1 and 2 were isolated from the aerial parts of Macrothelypteris torresiana （Gaud.） Ching. The structures of two products were identified as （2S）-5,7,2＇,5＇-tetrahydroxyflavanone-2＇-O-β-D-6＂-O-acetylglucopyranoside and （2S）- 5,7,2＇,5＇-tetrahydroxyflavanone-2＇-O-β-D-glucopyranoside on the basis of their chemical and spectral analysis, respectively.展开更多
文摘To search for the protective actions of blumea flavanones (BFs) on hepatocytes and hepatic subcellular organelle against lipid peroxidation, monkey′s hepatocytes were isolated and cultured with or without blumea flavanones, then damaged by FeSO 4 cysteine or CCl 4. The lipid peroxidation (malondialdehyde production) and alteration in hepatocyte membrane (leakage of GPT) were estimated. Hepatic subcellular organelles were also isolated and incubated with or without blumea flavanones, then injured by FeSO 4 ascorbate. The generation of malondialdehyde(MDA) was measured. It was found that BFs 10 and 100 μmol·L 1 inhibited the MDA generation and GPT (glutamic pyruvic transaminase) leakage out of hepatocytes that were induced by CCl 4 or FeSO 4 cysteine. BFs could prevent lipid peroxidation initiated by FeSO 4 ascorbate in subcellular organelle suspension. Among BFs, BF 2 possessed the strongest activity. Conclusion: Blumea flavanones possess antioxidation activities that protect monkey′s hepatocytes and hepatic subcellular organelle against injuries induced by FeSO4 or CCl 4.
文摘Two new lavandulylated flavanones,（2R, 3R）-8-1avandulyl-2＇-methoxy-5, 7, 4＇-trihydroxyflavanonol （1） and 8-1avandulyl-5,7, 4＇-trihydroxyflavonol （2）,were isolated from the dry roots of S opharaflavescens.Their structures were eiucidated on the basis of spectroscopic data. Compounds 1 and 2 exhibited significant antibacterial activities.
文摘The influence of different alcohol modifiers in mobile phase on the chiral separation of 4-methoxyl flavanone, 5-methoxyl flavanone and 6-methoxyl flavanone on cellulose tris (3, 5-dimethylphenylcarbamate) (CDMPC) column was studied and the chiral recognition mechanism was discussed. Using hexane-tert-butanol (1.31 mol L-1) as the mobile phase, those three methoxyl flavanones were excellently separated on CDMPC chiral column.
文摘In the present study,synthetic chalcones,flavanones and Schiff bases were prepared starting from paraceamol,and evaluated their anticipated anti-inflammatory activity.Chalcones were synthesized by reacting 3-acetyl-4-hydroxy acetanilide and aromatic aldehydes in alcoholic potassium hydroxide(KOH) solution under Claisen-Schmidt condensation conditions.The chalcones were cyclized in the presence of piperidine in isoamyl alcohol to obtain flavonone derivatives.Schiff bases were synthesized by condensing 3-acetyl-4-hydroxy anilines with aromatic aldehydes in the presence of HCl.These Schiff bases were further reacted with other aromatic aldehydes in alcoholic KOH solution.PASS cheminformatics software was used to predict the anti-inflammatory activity of synthesized compounds.PASS software predicted that chalcone-based Schiff bases 6a–d contained structural features that can exhibit anti-inflammatory activity.All the prepared derivatives of acetaminophen exhibited moderate to excellent in vivo anti-inflammatory activity in carrageenan-induced edema in rat paw.All the Schiff bases coupled chalcones showed good anti-inflammatory activity compared with the reference drug,diclofenac.Further evaluation of their therapeutic potential and safety profile is required in the future study.
基金supported by National Natural Science Foundation of China(Nos.81973199,82173949,and 81773864)the Key Research and Development Project of Shandong Province(No.2021CXGC010507)。
文摘Six novel compounds,comprising three quinolones(1a,1b,and 2)and three flavanones(3-5),along with seven known analogs(6-13),were isolated from the 95%EtOH extract of the stems and leaves of Glycosmis craibii var.glabra.The structures of the new compounds were elucidated using HR-ESI-MS,UV,and 1D and 2D nuclear magnetic resonance(NMR)data analysis.The ab-solute configurations were determined through Mosher ester and electronic circular dichroism(ECD)spectral analysis.Compounds 2,6,9,and 10 demonstrated inhibition of nitric oxide(NO)production stimulated by lipopolysaccharide in BV-2 microglial cells,with IC50 values ranging from 13.5 to 20.1 μmol·L^(-1),comparable to the positive control,dexamethasone.
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.
文摘Syzygium campanulatum Korth is a plant, which is a rich source of secondary metabolites （especially flavanones, chalcone, and triterpenoids）. In our present study, three conventional solvent extraction （CSE） techniques and supercritical fluid extraction （SFE） techniques were performed to achieve a maximum recovery of two flavanones, chalcone, and two triterpenoids from S. campanulatum leaves. Furthermore, a Box-Behnken design was constructed for the SFE technique using pressure, temperature, and particle size as independent variables, and yields of crude extract, individual and total secondary metabolites as the dependent variables. In the CSE procedure, twenty extracts were produced using ten different solvents and three techniques （maceration, soxhletion, and reflux）. An enriched extract of five secondary metabolites was collected using n-hexane：methanol （1：1） soxhletion. Using food-grade ethanol as a modifier, the SFE methods produced a higher recovery （25.5%-84.9%） of selected secondary metabo- lites as compared to the CSE techniques （0.92%-66.00%）.
文摘To identify bioactive compound in pigeon pea leaves (Cajanus cajan) that inhibits Salmonella thypi (S. thypi).MethodsThe leaf sample was powdered and macerated with methanol and fractioned by liquid-liquid extraction using ethyl acetate. The fraction was chromatographed and the isolates were identified for major component with liquid chromatography-mass spectrometry and the antibacterial activity was tested against S. thypi by Kirby-Bauer method.ResultsSubfraction 1 from the ethyl acetate fraction formed a yellowish solid with m/z 272, identified as naringenin. The naringenin-rich fraction shows fairly well inhibitory toward S. thypi in comparison with chloramphenicol.ConclusionsNaringenin shows antibacterial activity and can be developed to treat typhoid.
文摘In this overview,the current knowledge of the constituents of flavonoids isolated from the roots of Sophora flavescens(kushen)is updated.Flavonoids consist of several classes,such as flavanones,flavonols,chalcones,isoflavones,biflavonoids,flavanols,and flavones.The most common compounds are kurarinone(KRN),sophoraflavanone G(SFG),2′-methoxykurarinone,kuraridine,isoxanthohumol,and formononetin.KRN and SFG are two major flavanones with more vital anticancer properties than other flavonoids.From the literature,the cytotoxic values of KRN and SFG are variable and depend on the type of cancer cells tested.The anticancer activities of these two flavonoids involve different molecular mechanisms.Clinical trials are needed before anticancer drugs from KRN and SFG can be developed.
文摘A new flavanone was isolated from the roots of Desmos cochinchinensis Lour Its chemical structure was elucidated by spectral analysis as 7 hydroxy 5 methoxy 8 formyl 6 methylflavanone, named desmosflavanone Ⅱ
基金We thank the National Natural Science Foundation （No. 20562010）；Ministry of National Education （No.203143）for financial support.
文摘The total synthesis of （±）-abyssinoflavanone V was first achieved through C-prenylation, selective protection of phenolic hydroxyl group, aldol condensation, cyclization and deprotection starting from cheap 4-hydroxybenzaldehyde and 2,4,6- trihydroxyacetophenone, with total yield 24%. All structures of new compounds were confirmed by IR, 1^H NMR and MS.
基金supported by the National Natural Science Foundation of China(Grant No.31871547)。
文摘Flavonoids are important bioactive components in Dendrobium officinale,a medicinal orchid.They are involved in many biological activities,including protecting plants against biotic and abiotic stresses.Research on the key genes related to flavonoid biosynthesis in D.officinale is limited.In this study,one of the key flavonoid biosynthesis genes,flavanone 3-hydroxylase(F3H),was characterized from D.officinale.The open reading frame of DoF3H was 1134 bp long and it encoded a 377-amino acid protein.The DoF3H protein showed considerably high homology with F3H proteins from other plant species and shared a common evolutionary ancestor with other F3Hs.DoF3H transcripts were detected in different organs of adult plants and mainly accumulated in flowers,followed by roots,stems and leaves,a pattern that was similar to the content of flavonoids.Recombinant DoF3H protein,which was localized in the cytosol,could convert naringenin to dihydrokaempferol.The mRNA levels of DoF3H were significantly induced by salt and cold stresses.Furthermore,the heterologous expression of DoF3H in Escherichia coli conferred it higher tolerance to salt and cold stresses.These results provide insight into the molecular function of DoF3H in the biosynthesis of flavonoids,and provide a new application for improvement of abiotic tolerance in D.officinale.
文摘A new flavanone （2S）-5, 7, 2＇, 5＇-tetrahydroxy-flavanone 1 together with a new flavanone glycoside （2S）-5, 7, 2＇, 5＇-tetrahydroxy-flavanone 7-O-13-D-glucopyranoside 2, were isolated from the dry roots of Scutellaria baicalensis. Their structures were elucidated on the basis of spectroscopic data.
基金financially supported by the National Natural Science Foundation(Nos.20562010,20962016)Ningxia Natural Science Foundation,Program for New Century Excellent Talents in University(No.NCET-09-0860)the National Basic Research Program 973 of China(No.2010CB534916)
文摘A facile approach for the first total synthesis of two naturally occurring geranylated flavonoids,（±）-puyanin 1 and（±）-4＇-O- methylbonannione 2 has been obtained with total yield 27%and 21%,respectively.The key steps were regioselective cyclization of geranylated trihydroxychalcone and regioselective geranylation of 2,4,6-trihydroxyacetophenone.
基金Supported by the Special Research Foundation of Beijing Municipal Bureau of Landscape and Forestry (No.Jingyuanlu 201005)the public welfareresearch special project in State Administration for Quality Supervision and Inspection and Quarantine (No. 201210209)
文摘The title compound of sakuranetin, a main active flavanone component, was first isolated from Populus tomentosa Carr. and characterized by X-ray single-crystal diffraction analysis It crystallizes in the monoclinic lattice, space group P21/c with a = 12.8531（12）, b = 5.7141（3）, c = 18.0355（12） A, β = 97.333（8）°, V = 1313.77（16） A^3, Z= 4, Mr = 286.27, C16H14O5,μ（MoKa） = 0.108 mm^-1, Dc = 1.447 g/cm^3, F（000） = 600, the final R = 0.0350 and wR = 0.0859 for 2571 independent reflections （Rint = 0.0246） which were used in all calculations. The molecular crystal structure of sakuranetin shows relative stereochemistry of 5,4′-dihydroxy-7-methoxyflavanone. Intermolecular hydrogen bonds together with the continuous π-π interactions construct the three-dimensional architecture of the title compound. The preliminary bioassay reveals that the title compound exhibits moderate anti-inflammatory activity in vitro against the nitric oxide release.
基金Supported by the Research Startup Fund of Jilin University,China(Nos.4305050102H8,4305050102B5)the Basic Research and Operational Costs of Jilin University,China(Nos.421031196604,450060445293)
文摘Benzyl and anthracenemethyl groups were respectively bonded to the N atoms of 3-aminopropyl functionalized mesoporous SBA-15（APS-SBA-15） to obtain two new base catalysts over which the condensation reaction of benzaldehyde and 2＇-hydroxyacetophenone was studied.Good catalytic activities and high selectivities for flavanones were obtained in solvent-free reactions,which is attributed to the effect of benzyl and anthracenemetyl groups on the base sites of catalysts and the steric hindrance of futher reaction of flavanone with benzaldehyde.
基金supported by the Natural Science Foundation of Zhejiang Province(LZ21C130004)the National Natural Science Foundation of China(U1903204)he Fundamental Research Funds of Shaoxing Keqiao Research Institute of Zhejiang Sci-Tech University(KYY2021004S)。
文摘Using naturally colored cotton(NCC)can eliminate dyeing,printing and industrial processing,and reduce sewage discharge and energy consumption.Proanthocyanidins(PAs),the primary coloration components in brown fibers,are polyphenols formed by oligomers or polymers of flavan-3-ol units derived from anthocyanidins.Three essential structural genes for flavanone and flavonoid hydroxylation encoding flavanone-3-hydroxylase(F3H),flavonoid 3’-hydroxylase(F3’H)and flavonoid 3’5’-hydroxylase(F3’5’H)are initially committed in the flavonoid biosynthesis pathway to produce common precursors.The three genes were all expressed predominantly in developing fibers of NCCs,and their expression patterns varied temporally and spatially among NCC varieties.In GhF3Hi,GhF3’Hi and GhF3’5’Hi silenced lines of NCC varieties XC20 and ZX1,the expression level of the three genes decreased in developing cotton fiber,negatively correlated with anthocyanidin content and fiber color depth.Fiber color depth and type in RNAi lines changed with endogenous gene silencing efficiency and expression pattern,the three hydroxylase genes functioned in fiber color formation.GhF3H showed functional differentiation among NCC varieties and GhF3’H acted in the accumulation of anthocyanin in fiber.Compared with GhF3’H,GhF3’5’H was expressed more highly in brown fiber with a longer duration of expression and caused lighter color of fibers in GhF3’5’H silenced lines.These three genes regulating fiber color depth and type could be used to improve these traits by genetic manipulation.
基金Supported by the National High-Tech Research and Development Program of China(No.2006AA09Z446)the Fund of State Key Laboratory of Natural and Biomimetic Drags+7 种基金 Peking UniversityChina(No.20080210)the Shanxi Provincial Foundation for Overseas Returned China(No.2009021005)the Program for the Top Young and Middle-aged Innovative Talents of Higher Learning Institutions of Shanxi Province China(No.20091041-1)the Innovative Program of Shanxi Medical University China (No.38)
文摘A series of new flavanone derivatives of farrerol was designed and synthesized as a potent inhibitor of vascular smooth muscle cells（VSMCs） vegetation according to a convenient method. The structures of all the synthesized compounds were confirmed by 1H NMR, 13C NMR and EIHR-MS. The biological activities of these compounds against VSMCs in vitro were evaluated. The assay results indicate that two compounds, 5,7-dihydroxy-6,8-dimethyl- 2-（2-nitrophenyl）chroman-4-one（7f） and 2,3-dibromo-4,5-dihydroxydiphenylmethanone（7j） exhibited high activity against VSMCs in vitro with IC50 values of 9.9 and 6.7 μmol/L, respectively, and the preliminary structure-activity relationship（SAR） was described.
基金supported by the National Natural Science Foundation(No20962016)Ningxia Natura Science Foundation(NoNZ1006)Program for New Century Excellent Talents in University(NoNCET- 09-0860)
文摘A facile approach for the first total synthesis of naturally occurring geranylated flavanoids sepicanin A has been obtained with total yield 16%starting from 2,4,6-trihydroxyacetophenone after four steps.The key step was the protic acids（HCl or p-TsOH）-catalyzed benzopyrone formation in a protic polar solvent by deprotection and cycUzation of chalcone in one step.
文摘Two new flavanone glycosides 1 and 2 were isolated from the aerial parts of Macrothelypteris torresiana （Gaud.） Ching. The structures of two products were identified as （2S）-5,7,2＇,5＇-tetrahydroxyflavanone-2＇-O-β-D-6＂-O-acetylglucopyranoside and （2S）- 5,7,2＇,5＇-tetrahydroxyflavanone-2＇-O-β-D-glucopyranoside on the basis of their chemical and spectral analysis, respectively.
