A new alkaloid, named sessilistemonamine D, was isolated from the roots of Stemona sessilifolia and the structure and relative configuration were determined on the basis of NMR and MS spectrometric data analysis.
As a part of the ongoing search for new constituents of Stemona species in China, chemical investigation of Stemona sessilifolia, a plant used in the traditional Chinese medicine to treat respiratory disorders, was ca...As a part of the ongoing search for new constituents of Stemona species in China, chemical investigation of Stemona sessilifolia, a plant used in the traditional Chinese medicine to treat respiratory disorders, was carried out. To identify the chemical components rapidly, a selected sample of S. sessilifolia containing bibenzyls was tested using LC-ESIMS and analyzed further using stop-flow LC-UV-NMR, which was sensitive for the detection of the main constituents. LC microfractions were collected using the LC-UV-NMR technique and HR-EIMS off-line analysis was cartied out on the collected fractions. This chemical screening strategy allowed for the on-line identification of the main constituents of S. sessilifolia and provided information that was useful for a further peak-guided isolation procedure. Using these methods, four bibenzyls were isolated: two known compounds, 3,5-dihydroxy-4-methyl bibenzyl(1) and 3, 5-dihydroxy-2'-methoxy-4-methyl bibenzyl ( 2 ), and two novel compounds, 3,3'-dihydroxy-5, 6'-dimethoxy bibenzyl(3) and 3,5-dihydroxy-2', 5'-dimethoxy bibenzyl (4).展开更多
Four new alkaloids, didehydroprotostemonine, isoprotostemonine, neostemonine and stemodiol, were isolated from the roots of a Chinese medicinal plant, Stemona japonica, collected form Zhejiang Province, southern China...Four new alkaloids, didehydroprotostemonine, isoprotostemonine, neostemonine and stemodiol, were isolated from the roots of a Chinese medicinal plant, Stemona japonica, collected form Zhejiang Province, southern China. Their structures were elucidated by extensive spectral analyses.展开更多
Two new alkaloids, maistemonine and oxymaistemonine were isolated from the roots of $temona mairei collected from Yunnan Province, southwest of China. Their structures were elucidated by 2D-NMR techniques including ~1...Two new alkaloids, maistemonine and oxymaistemonine were isolated from the roots of $temona mairei collected from Yunnan Province, southwest of China. Their structures were elucidated by 2D-NMR techniques including ~1H-~1H COSY, ^(13)C-~1H-COSY, NOESY and other spectral analyses.展开更多
A novel alkaloid was isolated from the stems and leaves of Stemona parviflora Wright. Based on the spectral methods, its structure was elucidated as parvineostemonine.
Three hitherto undescribed Stemona alkaloids,named stemajapines A-C(1-3),along with six known alkaloids(4-9),were isolated and identified from the roots of Stemona japonica(Blume)Miq.(Stemonaceae).Their structures wer...Three hitherto undescribed Stemona alkaloids,named stemajapines A-C(1-3),along with six known alkaloids(4-9),were isolated and identified from the roots of Stemona japonica(Blume)Miq.(Stemonaceae).Their structures were established by the analysis of the mass data,NMR spectra,and computational chemistry.Stemjapines A and B were degraded maistemonines without spiro-lactone ring and skeletal methyl from maistemonine.Concurrence of alkaloids 1 and 2 revealed an undescribed way to form diverse Stemona alkaloids.Bioassay results disclosed the anti-inflammatory natural constituents stemjapines A and C with IC_(50) values of 19.7 and 13.8μM,respectively,compared to positive control dexamethasone with 11.7μM.The findings may point out a new direction of Stemona alkaloids inaddition to its traditional antitussive and insecticide activities.展开更多
Two new alkaloids namely tuberostemoninal and tuberostemoamide as minor components were isolated from the roots of Stemona tubeross.Their structures were determined by various 2D NMR and other spectra and finally conf...Two new alkaloids namely tuberostemoninal and tuberostemoamide as minor components were isolated from the roots of Stemona tubeross.Their structures were determined by various 2D NMR and other spectra and finally confirmed by X-ray analysis.展开更多
文摘A new alkaloid, named sessilistemonamine D, was isolated from the roots of Stemona sessilifolia and the structure and relative configuration were determined on the basis of NMR and MS spectrometric data analysis.
基金Supported by Science and Technology Committee of Shanghai, P R China(No 036505003)
文摘As a part of the ongoing search for new constituents of Stemona species in China, chemical investigation of Stemona sessilifolia, a plant used in the traditional Chinese medicine to treat respiratory disorders, was carried out. To identify the chemical components rapidly, a selected sample of S. sessilifolia containing bibenzyls was tested using LC-ESIMS and analyzed further using stop-flow LC-UV-NMR, which was sensitive for the detection of the main constituents. LC microfractions were collected using the LC-UV-NMR technique and HR-EIMS off-line analysis was cartied out on the collected fractions. This chemical screening strategy allowed for the on-line identification of the main constituents of S. sessilifolia and provided information that was useful for a further peak-guided isolation procedure. Using these methods, four bibenzyls were isolated: two known compounds, 3,5-dihydroxy-4-methyl bibenzyl(1) and 3, 5-dihydroxy-2'-methoxy-4-methyl bibenzyl ( 2 ), and two novel compounds, 3,3'-dihydroxy-5, 6'-dimethoxy bibenzyl(3) and 3,5-dihydroxy-2', 5'-dimethoxy bibenzyl (4).
文摘Four new alkaloids, didehydroprotostemonine, isoprotostemonine, neostemonine and stemodiol, were isolated from the roots of a Chinese medicinal plant, Stemona japonica, collected form Zhejiang Province, southern China. Their structures were elucidated by extensive spectral analyses.
文摘Two new alkaloids, maistemonine and oxymaistemonine were isolated from the roots of $temona mairei collected from Yunnan Province, southwest of China. Their structures were elucidated by 2D-NMR techniques including ~1H-~1H COSY, ^(13)C-~1H-COSY, NOESY and other spectral analyses.
基金supported by the National Natural Science Foundation of China (No. 30123005) and Bicoll Biotechnology Shanghai Co Ltd. Authors thank Professor Qiong Xin ZHONG (Department of Biological Science Hainan Normal University) for collecting Stemona parviflora
文摘A novel alkaloid was isolated from the stems and leaves of Stemona parviflora Wright. Based on the spectral methods, its structure was elucidated as parvineostemonine.
文摘Three hitherto undescribed Stemona alkaloids,named stemajapines A-C(1-3),along with six known alkaloids(4-9),were isolated and identified from the roots of Stemona japonica(Blume)Miq.(Stemonaceae).Their structures were established by the analysis of the mass data,NMR spectra,and computational chemistry.Stemjapines A and B were degraded maistemonines without spiro-lactone ring and skeletal methyl from maistemonine.Concurrence of alkaloids 1 and 2 revealed an undescribed way to form diverse Stemona alkaloids.Bioassay results disclosed the anti-inflammatory natural constituents stemjapines A and C with IC_(50) values of 19.7 and 13.8μM,respectively,compared to positive control dexamethasone with 11.7μM.The findings may point out a new direction of Stemona alkaloids inaddition to its traditional antitussive and insecticide activities.
文摘Two new alkaloids namely tuberostemoninal and tuberostemoamide as minor components were isolated from the roots of Stemona tubeross.Their structures were determined by various 2D NMR and other spectra and finally confirmed by X-ray analysis.
文摘目的:研究直立百部Stemona sessilifolia(Miq.) Miq.根中的化学成分.方法:运用各种色谱方法进行分离纯化,根据理化性质和波谱数据鉴定化合物的结构.结果:从直立百部中分离得到9个化合物,分别鉴定为Protostemotinine (1)、Stemospironine (2)、Stilbostemin B (3)、Stilbostemin D (4)、4'-Methylpinosylvin(5)、芝麻素(6)、28-羟基-正二十八烷酸-3'-甘油单酯(7)、26-羟基-正二十六烷酸-3'-甘油单酯(8)及β-谷甾醇(9).结论:化合物2~8为首次从该植物中分离得到.