Homoisoflavonoids are in the subclass of the larger family of flavonoids having one more alkyl carbon than flavonoids. Among them, 8-C-Methylated homoisoflavones have not been extensively studied for synthesis and bio...Homoisoflavonoids are in the subclass of the larger family of flavonoids having one more alkyl carbon than flavonoids. Among them, 8-C-Methylated homoisoflavones have not been extensively studied for synthesis and biological evaluation. Author’s current objective is to synthesize 8-C-Methylated homoisoflavones by the reaction of 3-C-methylated dihydrochalcones with N,N’-dimethyl (chloromethylene) ammonium chloride generated<em> in situ</em> from DMF and PCl<sub>5</sub> for one carbon extension at about room temperature. The 3-C-methylated dihydrochalcones were synthesized by the reduction of 3-C-methylated chalcones, which were prepared from 3-C-methylated acetophenones and aromatic aldehydes in the presence of base. All the synthesized novel homoisoflavones’s structures were characterized by NMR and Tandem Mass Spectrometry.展开更多
A novel phenylpropanoid-substituted catechin glycoside glabraoside A 1 and a new dihydrochalcone 3＇-（7＂-allylphenyl）-2＇,4＇,4＂-trihydroxy-6＇-methoxydihydrochalcone 2 were isolated from the herbs of Sarcandra gl...A novel phenylpropanoid-substituted catechin glycoside glabraoside A 1 and a new dihydrochalcone 3＇-（7＂-allylphenyl）-2＇,4＇,4＂-trihydroxy-6＇-methoxydihydrochalcone 2 were isolated from the herbs of Sarcandra glabra. Their structures were elucidated on the basis of spectroscopic analyses and chiroptical methods.展开更多
Objective:To isolate and identify the major bioactive components from the leaves of Lysiphyllum strychnifolium,an indigenous herb used in traditional Thai medicine for detoxification,longevity,and some other health re...Objective:To isolate and identify the major bioactive components from the leaves of Lysiphyllum strychnifolium,an indigenous herb used in traditional Thai medicine for detoxification,longevity,and some other health related issues.Methods:Comparative HPLC analyses of the crude extracts from three provenances were carried out for an overview of characteristic compound profiles.Isolation of the major compounds was undertaken with chromatographic methods.Chemical structures were elucidated by NMR spectroscopic techniques and mass spectrometry.DPPH scavenging assay was carried out to determine the free radical scavenging activity of isolated compounds.Results:Yanangdaengin(3),a dihydrochalcone glucoside galloyl ester,has been isolated together with its corresponding dihydrochalcone glucoside trilobatin(2)as major compounds from the leaves of L.strychnifolium.Additionally,gallic acid(1)was co-chromatographically identified.Free radical scavenging activity of isolated compounds were determined.Compound 3 exhibited higher free radical scavenging activities in comparison to Trolox and quercetin.Conclusion:The isolated compounds could be used as chemical markers for quality assessment.The present work could promote the quality control and herbal medicinal product development of this plant.展开更多
文摘Homoisoflavonoids are in the subclass of the larger family of flavonoids having one more alkyl carbon than flavonoids. Among them, 8-C-Methylated homoisoflavones have not been extensively studied for synthesis and biological evaluation. Author’s current objective is to synthesize 8-C-Methylated homoisoflavones by the reaction of 3-C-methylated dihydrochalcones with N,N’-dimethyl (chloromethylene) ammonium chloride generated<em> in situ</em> from DMF and PCl<sub>5</sub> for one carbon extension at about room temperature. The 3-C-methylated dihydrochalcones were synthesized by the reduction of 3-C-methylated chalcones, which were prepared from 3-C-methylated acetophenones and aromatic aldehydes in the presence of base. All the synthesized novel homoisoflavones’s structures were characterized by NMR and Tandem Mass Spectrometry.
基金the National Natural Science Foundation of China （No. 20432030） for financial support.
文摘A novel phenylpropanoid-substituted catechin glycoside glabraoside A 1 and a new dihydrochalcone 3＇-（7＂-allylphenyl）-2＇,4＇,4＂-trihydroxy-6＇-methoxydihydrochalcone 2 were isolated from the herbs of Sarcandra glabra. Their structures were elucidated on the basis of spectroscopic analyses and chiroptical methods.
基金financial support provided by Thammasat University Research Fund under the TU Research Scholar,Contract No.2/29/2561。
文摘Objective:To isolate and identify the major bioactive components from the leaves of Lysiphyllum strychnifolium,an indigenous herb used in traditional Thai medicine for detoxification,longevity,and some other health related issues.Methods:Comparative HPLC analyses of the crude extracts from three provenances were carried out for an overview of characteristic compound profiles.Isolation of the major compounds was undertaken with chromatographic methods.Chemical structures were elucidated by NMR spectroscopic techniques and mass spectrometry.DPPH scavenging assay was carried out to determine the free radical scavenging activity of isolated compounds.Results:Yanangdaengin(3),a dihydrochalcone glucoside galloyl ester,has been isolated together with its corresponding dihydrochalcone glucoside trilobatin(2)as major compounds from the leaves of L.strychnifolium.Additionally,gallic acid(1)was co-chromatographically identified.Free radical scavenging activity of isolated compounds were determined.Compound 3 exhibited higher free radical scavenging activities in comparison to Trolox and quercetin.Conclusion:The isolated compounds could be used as chemical markers for quality assessment.The present work could promote the quality control and herbal medicinal product development of this plant.
