Ten novel xanthones,garpedunxanthones A-G(1-5,6a/6b,7a/7b) and nujiangxanthone Q(8),along with sixteen known analogs(9-24),were isolated from Garcinia pedunculata and G.nujiangensis.Their structures were elucidated th...Ten novel xanthones,garpedunxanthones A-G(1-5,6a/6b,7a/7b) and nujiangxanthone Q(8),along with sixteen known analogs(9-24),were isolated from Garcinia pedunculata and G.nujiangensis.Their structures were elucidated through high-resolution electrospray ionization mass spectrometry(HR-ESI-MS) data,comprehensive nuclear magnetic resonance(NMR) spectroscopic analyses,and electronic circular dichroism(ECD) calculations.All compounds without cytotoxicity were assessed for anti-inflammatory properties by measuring the inhibition of nitric oxide(NO) production in lipopolysaccharide(LPS)-induced RAW264.7cells.Structure-activity relationships are also discussed.Compounds 7b,19,and 21 exhibited significant anti-inflammatory activity with IC_(50) values of 16.44±0.69,14.28±0.78,and 10.67±3.28 μmol·L^(-1),respectively.Enzyme-linked immunosorbent assay(ELISA) demonstrated that compounds 7b,19,and 21 inhibited the expression of pro-inflammatory cytokines TNF-α and IL-6 in a dose-dependent manner.The inhibitory effect of compo und 21 on IL-6 at 20 μmol·L^(-1)was comparable to that of the positive control.In network pharmacology studies,potential targets of compounds and inflammation were identified from PharmMapper and GeneCards databases.Gene Ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) enrichment analysis revealed that the overlapped targets were intricately associated with major pathogenic processes linked to inflammation,including positive regulation of mitogen-activated protein kinase(MAPK) cascade,protein kinase activity,NO synthase regulator activity,MAPK signaling pathway,and EGFR tyrosine kinase inhibitor resistance.展开更多
Plants have so much to offer as far as the discovery of new bioactive molecules is concerned.Among the several classes of phytochemicals,xanthones offer greater structural diversity and pharmacological value.They are ...Plants have so much to offer as far as the discovery of new bioactive molecules is concerned.Among the several classes of phytochemicals,xanthones offer greater structural diversity and pharmacological value.They are variable but definitely antioxidant in nature.Thus they are attractive targets for natural product and medicinal chemists.Xanthones and their glycosides possess broad spectrum interesting biological activities,such as cytotoxic,anti-inflammatory,antioxidant,anti-bacterial,neuroprotective,anti-HIV,enzyme inhibition,and hypoglycemic.The radical scavenging ability of these molecules accounts for most of their added therapeutic values.This paper intended to serve as a guide for future endeavors in quest for these molecules.Structure-Activity Relationship(SAR)and mechanism of action is given for better understanding of their role as pharmacological agents.The most recent advances in the isolation of bioactive xanthones and their glycosides were presented here.This paper will assist in directed approaches towards the discovery of analogues of xanthones.展开更多
From the CHCl3 part of Swertia decora Franch., a traditional medicinal herb of China, two new xanthones, swertiadecoraxanthone-I and swertiadecoraxanthone-II along with four known compounds have been isolated and iden...From the CHCl3 part of Swertia decora Franch., a traditional medicinal herb of China, two new xanthones, swertiadecoraxanthone-I and swertiadecoraxanthone-II along with four known compounds have been isolated and identified on the basis of spectral analysis and chemical evidence.展开更多
The present study was designed to investigate the chemical constituents of the roots of Cudrania fruticosa Wight. Compounds were isolated by various column chromatographic methods including silica gel, polyamide, seph...The present study was designed to investigate the chemical constituents of the roots of Cudrania fruticosa Wight. Compounds were isolated by various column chromatographic methods including silica gel, polyamide, sephadex LH-20, and semi-preparative HPLC. Their structures were elucidated by a combination of 1D and 2D NMR techniques, mass spectrometry, and chemical methods. Two new xanthones, Cudraxanthone T and U(1-2), along with four known compounds(3-6) were isolated from the roots of Cudrania fruticosa Wight.展开更多
Two new xanthone glycosides, polygalaxanthone IV and V were isolated from the roots of Polygala tenuifolia Willd. Their structures were established as 6-O-[a-L-rhamnopyranosyl- (12)-b-D-glucopyranosyl]-1-hydroxy-3, 7...Two new xanthone glycosides, polygalaxanthone IV and V were isolated from the roots of Polygala tenuifolia Willd. Their structures were established as 6-O-[a-L-rhamnopyranosyl- (12)-b-D-glucopyranosyl]-1-hydroxy-3, 7-dimethoxyxanthone (polygalaxanthone IV), and 6-O- [a-L-rhamnopyranosyl-(12)-b-D-glucopyranosyl]-1, 3-dihydroxy-7-methoxyxanthone (polyga- laxanthone V), respectively, on the basis of chemical and spectral evidence.展开更多
Eight known compounds were isolated from the whole plants ofArenaria serpyllifolia L. by solvent fractionation and subsequent separations with silica gel, ODS, Sephadex LH-20 and semi-preparative HPLC chromatography. ...Eight known compounds were isolated from the whole plants ofArenaria serpyllifolia L. by solvent fractionation and subsequent separations with silica gel, ODS, Sephadex LH-20 and semi-preparative HPLC chromatography. Their structures were determined by spectroscopic analysis and identified as quercetin （1）, quercetin 7-O-α-L-rhamnoside （2）, quercetin 3-O-α-L- rhamnoside （3）, 3-O-methyl quercetin （4）, 1,5-dihydroxyxanthone （5）, 1,5-dihydroxyxanthone-6-O-β-D-glucoside （6）, 5-hydroxy- l-methoxyxanthone （7） and 6-deoxyisojacareubin （8）. All these compounds were isolated from this title plant for the first time, and compounds 5-8 were obtained from genus Arenaria for the first time.展开更多
In an attempt to identify bioactive compounds from a Tibetan medicinal herb Halenia elliptica, four known compounds were isolated. The crystal structure of the title compound 1-hydroxy-2,3,4,7-tetramethoxyxanthone was...In an attempt to identify bioactive compounds from a Tibetan medicinal herb Halenia elliptica, four known compounds were isolated. The crystal structure of the title compound 1-hydroxy-2,3,4,7-tetramethoxyxanthone was characterized by X-ray single-crystal structure analysis. The crystal belongs to monoclinic, space group P21/n with a = 7.155(2), b = 13.232(1), c = 16.037(2) ? b = 95.06(2), V = 1512.4(5) 3, C17H16O7, Mr = 332.30, Z = 4, Dc = 1.459 g/cm3, l(MoKa) = 0.71073 ? m(MoKa) = 1.15 cm-1 and F(000) = 696. It exhibits a characteristic approximate plane structure consisting of 13 carbon atoms (C(1) to C(13)) and all of the seven oxygen atoms (O(1) to O(7)). An intra-hydrogen bond was formed between O(6) and O(5)H(5).展开更多
As a widely used traditional Chinese medicine （TCM）, Swertia punicea Hemsl has exhibited effects on anti-hepatitis B virus （HBV）, liver protection, hypoglycemic activity and cholecystitis. In this study, we confir...As a widely used traditional Chinese medicine （TCM）, Swertia punicea Hemsl has exhibited effects on anti-hepatitis B virus （HBV）, liver protection, hypoglycemic activity and cholecystitis. In this study, we confirmed that xanthone extract from Swertia punicea Hemsl （XSPH） improved the motor deficit, increased the levels of striatal dopamine （DA） and homovanilic acid （HVA）, and alleviated the loss of tyrosine hydroxylase （TH）-positive neurons located in substantia nigra pars compacta （SNpc） in MPTP-induced mouse model of Parkinson＇s disease （PD）. In conclusion, the present results indicated that XSPH offered neuroprotective effects against the neurotoxicity of MPTP and it might be a potential treatment for PD.展开更多
AIM: To develop and validate a high performance liquid chromatography(HPLC) coupled with diode array and evaporative light scattering detectors(DAD-ELSD) method for the quantitative determination and fingerprint analy...AIM: To develop and validate a high performance liquid chromatography(HPLC) coupled with diode array and evaporative light scattering detectors(DAD-ELSD) method for the quantitative determination and fingerprint analysis of ten active constituents in three chemical classes(namely, xanthone glycosides, steroidal saponins, and alkaloids) in Zhimu-Huangbai herb pair(ZB). METHOD: Chromatographic separation was performed on a Diamonsil C18 column(4.6 mm × 250 mm, 5 μm, Dikma) by gradient elution using acetic acid in acetonitrile solution at a flow rate of 1.0 mL·min–1 at 260 nm. The drift tube temperature of ELSD was set to 60 ℃ and nebulizer gas pressure was 4.0 Bar. Method validation was performed to assure its linearity, limits of detection and quantification, precision, repeatability, stability, and accuracy. RESULTS: The HPLC-DAD-ELSD method allowed the quantification of ten compounds(phellodendrine, jatrorrhizine, palmatine, berberine, neomangiferin, mangiferin, timosaponin E-I, timosaponin B-II, timosaponin B, and timosaponin A-III), and was successfully applied to fingerprint analysis for ten batches of ZB samples. CONCLUSION: This was the first time to apply the combination of DAD and ELSD for the simultaneous determination of ten active ingredients in ZB. The results showed that the combination of quantitative analysis for marker ingredients and chemical fingerprint for the TCM herb pair provides a potentially powerful, widely introduced, and internationally accepted strategy for assessment of complex TCM formulas.展开更多
Metabolism study has been carried out on 1-hydroxy-2,3,5-trimethoxyxanthone （HM-1） and 1-hydroxy-2,3,4,7- tetramethoxyxanthone （HM-2）, which are two biologically active ingredients isolated from the Tibetan herb, ...Metabolism study has been carried out on 1-hydroxy-2,3,5-trimethoxyxanthone （HM-1） and 1-hydroxy-2,3,4,7- tetramethoxyxanthone （HM-2）, which are two biologically active ingredients isolated from the Tibetan herb, Halenia elliptica D. Don., in rat liver microsomes in vitro. A method of high performance liquid chromatography coupled to ion trap time-of-flight mass spectrometry （LCMSn-ESI-IT-TOF） was applied to analyze metabolites of HM-1 and HM-2 on line, and five metabolites were identified containing 1,5-dihydroxy-2,3-dimethoxyxanthone （HM-5）, 1,7-dihydroxy-2,3,4-trimethoxyxanthone （HM-9）, 1,4, 7- trihydroxy-2,3-dimethoxyxanthone （HM-10）, 1,4-dihydroxy-2,3,7-trimethoxyxanthone （HM-11） and 1,2-dilaydroxy-3,4,7- trimethoxyxanthone （HM-12）. Among these metabolites, HM-9, HM-11, and HM-12 were isomers mutually. The results indicated that HM-1 and HM-2 occurred Phase I metabolic reaction of demethylation in rat microsomes in vitro.展开更多
In order to study the relationship between biological and pharmacological activities with their structures, a series of tri- and tetra-oxygenated xanthones including 1-hydroxyl-2,3,4,7- tetramethoxy xanthone 1, 1-hydr...In order to study the relationship between biological and pharmacological activities with their structures, a series of tri- and tetra-oxygenated xanthones including 1-hydroxyl-2,3,4,7- tetramethoxy xanthone 1, 1-hydroxyl-2,3,4,5-tetramethoxyl xanthone 2, 1-hydroxyl-3,5-dimethoxy- xanthone 3, 1,8-dihydroxyl-3,5-dimethoxyl xanthone 4 and 1,5,8-trihydroxyl-3-methoxy xanthone 5 have been isolated from Swertia chirayita. Their structures were established on the basis of spectral and chemical evidences. The crystal structure of 5 was also investigated by single-crystal X-ray diffraction analysis. It crystallizes in the triclinic system, space group P?with a = 7.1540(10), b = 7.520(2), c = 10.671(2) , V = 562.7(2) 3 , α = 86.50(3), β = 80.06(3) , γ = 85.00(3), Z = 2, Dc = 1.618 g/m3, R = 0.0405, wR = 0.1028 and F(000) = 284. The molecular structure of 5 is nearly planar and four substituents are much closer to the plane. Compound 5 contains three intermolecular hydro- gen bonds. A recent study shows that phenolic hydroxyls in xanthones are the main active groups capable of scavenging OH and O2.展开更多
Two novel xanthones, 1,6-dihydroxy-4,5-dimethoxyxanthone （1） and 1,5,6-trihydroxy-7,8-di（3-methyl-2-butenyl）-6＇,6＇-dimethylpyrano（2＇,3＇：3,4）xanthone （2） were isolated from the bark of Garcinia xanthochymu...Two novel xanthones, 1,6-dihydroxy-4,5-dimethoxyxanthone （1） and 1,5,6-trihydroxy-7,8-di（3-methyl-2-butenyl）-6＇,6＇-dimethylpyrano（2＇,3＇：3,4）xanthone （2） were isolated from the bark of Garcinia xanthochymus by normal phase and reverse phase silica gel column chromatography. Their structures were elucidated by spectroscopic methods, especially 2D-NMR techniques.展开更多
Chemical examination of an EtOAc extract of cultured Aspergillus versicolor fungus from deep-sea sediments resulted in the isolation of four xanthones, eight anthraquinones and five alkaloids, including a new xanthone...Chemical examination of an EtOAc extract of cultured Aspergillus versicolor fungus from deep-sea sediments resulted in the isolation of four xanthones, eight anthraquinones and five alkaloids, including a new xanthone, oxisterigmatocystin D （1） and a new alkaloid, aspergillusine A （13）. High resolution electron impact mass spectrometry （HR-EI-MS）, FT-IR spectroscopy, and NMR techniques were used to elucidate the structures of these compounds, and the absolute configuration of compound 1 was established by its NMR features and coupling constant. Furthermore, the biosynthesis pathway of these xanthones and anthraquinones were deduced, and their antioxidant activity and cytotoxicity in human cancer cell lines （HTC-8, Bel-7420, BGC-823, A549, and A2780） were evaluated. The trolox equivalent antioxidant capacity （TEAC） assay indicated most of the xanthones and anthraquinones possessing moderate antioxidant activities. The Nrf2-dependent luciferase reporter gene assay revealed that compounds 6, 7, 9, and 12 potentially activated the expression of Nrf2-regulated gene. In addition, compounds 5 and 11 showed weak cytotoxicity on A549 with the ICs0 values of 25.97 and 25.60 gmol·L^-1, respectively.展开更多
A new caged polyprenylated xanthone, gambogic aldehyde （1）, was isolated from the resin of Garcinia hanburyi. Its structure was elucidated on the basis of spectral data including 1D and 2D NMR data. In addition, the...A new caged polyprenylated xanthone, gambogic aldehyde （1）, was isolated from the resin of Garcinia hanburyi. Its structure was elucidated on the basis of spectral data including 1D and 2D NMR data. In addition, the antiproliferative ability of compound 1 was determined in mouse leukemia P388 and P388/ADR cells.展开更多
文摘Ten novel xanthones,garpedunxanthones A-G(1-5,6a/6b,7a/7b) and nujiangxanthone Q(8),along with sixteen known analogs(9-24),were isolated from Garcinia pedunculata and G.nujiangensis.Their structures were elucidated through high-resolution electrospray ionization mass spectrometry(HR-ESI-MS) data,comprehensive nuclear magnetic resonance(NMR) spectroscopic analyses,and electronic circular dichroism(ECD) calculations.All compounds without cytotoxicity were assessed for anti-inflammatory properties by measuring the inhibition of nitric oxide(NO) production in lipopolysaccharide(LPS)-induced RAW264.7cells.Structure-activity relationships are also discussed.Compounds 7b,19,and 21 exhibited significant anti-inflammatory activity with IC_(50) values of 16.44±0.69,14.28±0.78,and 10.67±3.28 μmol·L^(-1),respectively.Enzyme-linked immunosorbent assay(ELISA) demonstrated that compounds 7b,19,and 21 inhibited the expression of pro-inflammatory cytokines TNF-α and IL-6 in a dose-dependent manner.The inhibitory effect of compo und 21 on IL-6 at 20 μmol·L^(-1)was comparable to that of the positive control.In network pharmacology studies,potential targets of compounds and inflammation were identified from PharmMapper and GeneCards databases.Gene Ontology(GO) and Kyoto Encyclopedia of Genes and Genomes(KEGG) enrichment analysis revealed that the overlapped targets were intricately associated with major pathogenic processes linked to inflammation,including positive regulation of mitogen-activated protein kinase(MAPK) cascade,protein kinase activity,NO synthase regulator activity,MAPK signaling pathway,and EGFR tyrosine kinase inhibitor resistance.
基金funding support from the National Natural Science Foundation of China (No. 81673579)Hunan Province Universities 2011 Collaborative Innovation Center of Protection and Utilization of Hu-Xiang Chinese Medicine ResourcesHunan Provincial Key Laboratory of Diagnostics in Chinese Medicine
文摘Plants have so much to offer as far as the discovery of new bioactive molecules is concerned.Among the several classes of phytochemicals,xanthones offer greater structural diversity and pharmacological value.They are variable but definitely antioxidant in nature.Thus they are attractive targets for natural product and medicinal chemists.Xanthones and their glycosides possess broad spectrum interesting biological activities,such as cytotoxic,anti-inflammatory,antioxidant,anti-bacterial,neuroprotective,anti-HIV,enzyme inhibition,and hypoglycemic.The radical scavenging ability of these molecules accounts for most of their added therapeutic values.This paper intended to serve as a guide for future endeavors in quest for these molecules.Structure-Activity Relationship(SAR)and mechanism of action is given for better understanding of their role as pharmacological agents.The most recent advances in the isolation of bioactive xanthones and their glycosides were presented here.This paper will assist in directed approaches towards the discovery of analogues of xanthones.
基金This work was supported in part by Shanghai Municipal Educational Committee (grants S970204).
文摘From the CHCl3 part of Swertia decora Franch., a traditional medicinal herb of China, two new xanthones, swertiadecoraxanthone-I and swertiadecoraxanthone-II along with four known compounds have been isolated and identified on the basis of spectral analysis and chemical evidence.
基金supported by the National Natural Science Foundation of China(No.81172949)the Program for Excellent Talents of Liaoning Province of China(No.LR2013058)
文摘The present study was designed to investigate the chemical constituents of the roots of Cudrania fruticosa Wight. Compounds were isolated by various column chromatographic methods including silica gel, polyamide, sephadex LH-20, and semi-preparative HPLC. Their structures were elucidated by a combination of 1D and 2D NMR techniques, mass spectrometry, and chemical methods. Two new xanthones, Cudraxanthone T and U(1-2), along with four known compounds(3-6) were isolated from the roots of Cudrania fruticosa Wight.
文摘Two new xanthone glycosides, polygalaxanthone IV and V were isolated from the roots of Polygala tenuifolia Willd. Their structures were established as 6-O-[a-L-rhamnopyranosyl- (12)-b-D-glucopyranosyl]-1-hydroxy-3, 7-dimethoxyxanthone (polygalaxanthone IV), and 6-O- [a-L-rhamnopyranosyl-(12)-b-D-glucopyranosyl]-1, 3-dihydroxy-7-methoxyxanthone (polyga- laxanthone V), respectively, on the basis of chemical and spectral evidence.
基金National Key Technology R&D Program"New Drug Innovation"of China(Grant No.2012ZX09301002-002-002,2012ZX09304-005)
文摘Eight known compounds were isolated from the whole plants ofArenaria serpyllifolia L. by solvent fractionation and subsequent separations with silica gel, ODS, Sephadex LH-20 and semi-preparative HPLC chromatography. Their structures were determined by spectroscopic analysis and identified as quercetin （1）, quercetin 7-O-α-L-rhamnoside （2）, quercetin 3-O-α-L- rhamnoside （3）, 3-O-methyl quercetin （4）, 1,5-dihydroxyxanthone （5）, 1,5-dihydroxyxanthone-6-O-β-D-glucoside （6）, 5-hydroxy- l-methoxyxanthone （7） and 6-deoxyisojacareubin （8）. All these compounds were isolated from this title plant for the first time, and compounds 5-8 were obtained from genus Arenaria for the first time.
文摘In an attempt to identify bioactive compounds from a Tibetan medicinal herb Halenia elliptica, four known compounds were isolated. The crystal structure of the title compound 1-hydroxy-2,3,4,7-tetramethoxyxanthone was characterized by X-ray single-crystal structure analysis. The crystal belongs to monoclinic, space group P21/n with a = 7.155(2), b = 13.232(1), c = 16.037(2) ? b = 95.06(2), V = 1512.4(5) 3, C17H16O7, Mr = 332.30, Z = 4, Dc = 1.459 g/cm3, l(MoKa) = 0.71073 ? m(MoKa) = 1.15 cm-1 and F(000) = 696. It exhibits a characteristic approximate plane structure consisting of 13 carbon atoms (C(1) to C(13)) and all of the seven oxygen atoms (O(1) to O(7)). An intra-hydrogen bond was formed between O(6) and O(5)H(5).
基金National key foundation for exploring scientific ins trument of China(Grant No.2013YQ030651)National Natural Sci ence Foundation of China(Grant No.81202937)
文摘As a widely used traditional Chinese medicine （TCM）, Swertia punicea Hemsl has exhibited effects on anti-hepatitis B virus （HBV）, liver protection, hypoglycemic activity and cholecystitis. In this study, we confirmed that xanthone extract from Swertia punicea Hemsl （XSPH） improved the motor deficit, increased the levels of striatal dopamine （DA） and homovanilic acid （HVA）, and alleviated the loss of tyrosine hydroxylase （TH）-positive neurons located in substantia nigra pars compacta （SNpc） in MPTP-induced mouse model of Parkinson＇s disease （PD）. In conclusion, the present results indicated that XSPH offered neuroprotective effects against the neurotoxicity of MPTP and it might be a potential treatment for PD.
基金supported by the Natural Science Foundation of Shanghai City,China(No.10411969800)the National Nature Science Foundation of China(Nos.81202866 and 81302856)
文摘AIM: To develop and validate a high performance liquid chromatography(HPLC) coupled with diode array and evaporative light scattering detectors(DAD-ELSD) method for the quantitative determination and fingerprint analysis of ten active constituents in three chemical classes(namely, xanthone glycosides, steroidal saponins, and alkaloids) in Zhimu-Huangbai herb pair(ZB). METHOD: Chromatographic separation was performed on a Diamonsil C18 column(4.6 mm × 250 mm, 5 μm, Dikma) by gradient elution using acetic acid in acetonitrile solution at a flow rate of 1.0 mL·min–1 at 260 nm. The drift tube temperature of ELSD was set to 60 ℃ and nebulizer gas pressure was 4.0 Bar. Method validation was performed to assure its linearity, limits of detection and quantification, precision, repeatability, stability, and accuracy. RESULTS: The HPLC-DAD-ELSD method allowed the quantification of ten compounds(phellodendrine, jatrorrhizine, palmatine, berberine, neomangiferin, mangiferin, timosaponin E-I, timosaponin B-II, timosaponin B, and timosaponin A-III), and was successfully applied to fingerprint analysis for ten batches of ZB samples. CONCLUSION: This was the first time to apply the combination of DAD and ELSD for the simultaneous determination of ten active ingredients in ZB. The results showed that the combination of quantitative analysis for marker ingredients and chemical fingerprint for the TCM herb pair provides a potentially powerful, widely introduced, and internationally accepted strategy for assessment of complex TCM formulas.
基金the supports of the National Natural Science Foundation of China(No.30873115)National Science and Technology Special Projects(Nos.2009zx09301-003-5-1 and 2009zx09301-003-7-1)supported by the analytical center of the Peking branch of Japanese Shimadzu Corporation to provide the LCMS~n-IT-TOF system
文摘Metabolism study has been carried out on 1-hydroxy-2,3,5-trimethoxyxanthone （HM-1） and 1-hydroxy-2,3,4,7- tetramethoxyxanthone （HM-2）, which are two biologically active ingredients isolated from the Tibetan herb, Halenia elliptica D. Don., in rat liver microsomes in vitro. A method of high performance liquid chromatography coupled to ion trap time-of-flight mass spectrometry （LCMSn-ESI-IT-TOF） was applied to analyze metabolites of HM-1 and HM-2 on line, and five metabolites were identified containing 1,5-dihydroxy-2,3-dimethoxyxanthone （HM-5）, 1,7-dihydroxy-2,3,4-trimethoxyxanthone （HM-9）, 1,4, 7- trihydroxy-2,3-dimethoxyxanthone （HM-10）, 1,4-dihydroxy-2,3,7-trimethoxyxanthone （HM-11） and 1,2-dilaydroxy-3,4,7- trimethoxyxanthone （HM-12）. Among these metabolites, HM-9, HM-11, and HM-12 were isomers mutually. The results indicated that HM-1 and HM-2 occurred Phase I metabolic reaction of demethylation in rat microsomes in vitro.
基金The project was supported by the Key Laboratory for Natural Medicine of Gansu Province and Foundation of Lanzhou University of Technology
文摘In order to study the relationship between biological and pharmacological activities with their structures, a series of tri- and tetra-oxygenated xanthones including 1-hydroxyl-2,3,4,7- tetramethoxy xanthone 1, 1-hydroxyl-2,3,4,5-tetramethoxyl xanthone 2, 1-hydroxyl-3,5-dimethoxy- xanthone 3, 1,8-dihydroxyl-3,5-dimethoxyl xanthone 4 and 1,5,8-trihydroxyl-3-methoxy xanthone 5 have been isolated from Swertia chirayita. Their structures were established on the basis of spectral and chemical evidences. The crystal structure of 5 was also investigated by single-crystal X-ray diffraction analysis. It crystallizes in the triclinic system, space group P?with a = 7.1540(10), b = 7.520(2), c = 10.671(2) , V = 562.7(2) 3 , α = 86.50(3), β = 80.06(3) , γ = 85.00(3), Z = 2, Dc = 1.618 g/m3, R = 0.0405, wR = 0.1028 and F(000) = 284. The molecular structure of 5 is nearly planar and four substituents are much closer to the plane. Compound 5 contains three intermolecular hydro- gen bonds. A recent study shows that phenolic hydroxyls in xanthones are the main active groups capable of scavenging OH and O2.
基金the National Natural Science Foundation of China （No. 30670215）
文摘Two novel xanthones, 1,6-dihydroxy-4,5-dimethoxyxanthone （1） and 1,5,6-trihydroxy-7,8-di（3-methyl-2-butenyl）-6＇,6＇-dimethylpyrano（2＇,3＇：3,4）xanthone （2） were isolated from the bark of Garcinia xanthochymus by normal phase and reverse phase silica gel column chromatography. Their structures were elucidated by spectroscopic methods, especially 2D-NMR techniques.
基金supported by the Knowledge Innovation Program of Shenzhen(JCYJ20160428181415376 andJCYJ20150529153646078)
文摘Chemical examination of an EtOAc extract of cultured Aspergillus versicolor fungus from deep-sea sediments resulted in the isolation of four xanthones, eight anthraquinones and five alkaloids, including a new xanthone, oxisterigmatocystin D （1） and a new alkaloid, aspergillusine A （13）. High resolution electron impact mass spectrometry （HR-EI-MS）, FT-IR spectroscopy, and NMR techniques were used to elucidate the structures of these compounds, and the absolute configuration of compound 1 was established by its NMR features and coupling constant. Furthermore, the biosynthesis pathway of these xanthones and anthraquinones were deduced, and their antioxidant activity and cytotoxicity in human cancer cell lines （HTC-8, Bel-7420, BGC-823, A549, and A2780） were evaluated. The trolox equivalent antioxidant capacity （TEAC） assay indicated most of the xanthones and anthraquinones possessing moderate antioxidant activities. The Nrf2-dependent luciferase reporter gene assay revealed that compounds 6, 7, 9, and 12 potentially activated the expression of Nrf2-regulated gene. In addition, compounds 5 and 11 showed weak cytotoxicity on A549 with the ICs0 values of 25.97 and 25.60 gmol·L^-1, respectively.
文摘A new caged polyprenylated xanthone, gambogic aldehyde （1）, was isolated from the resin of Garcinia hanburyi. Its structure was elucidated on the basis of spectral data including 1D and 2D NMR data. In addition, the antiproliferative ability of compound 1 was determined in mouse leukemia P388 and P388/ADR cells.
