Two racemic pairs of new stilbenoid dimers,(±)-heterosmilaxones A(1)and B(2),with unique 6/6/6and 6/5/7 tricyclic core systems,respectively,were isolated from the rhizomes of Heterosmilax yunnanensis.Their struct...Two racemic pairs of new stilbenoid dimers,(±)-heterosmilaxones A(1)and B(2),with unique 6/6/6and 6/5/7 tricyclic core systems,respectively,were isolated from the rhizomes of Heterosmilax yunnanensis.Their structures were elucidated through comprehensive spectroscopic analyses,quantum chemical calculations and X-ray diffraction crystallography.Compound(+)-1,initially reported as syagrusin A with a 1,4,4a,9a-tetrahydrofluoren-9-one skeleton,is now revised to a new structure characteristic with a benzo bicyclo[3.3.1]nonene scaffold.And compound 2 bears an unprecedented carbon skeleton with four continuous chiral centers in the central benzo bicyclo[4.2.1]nonene motif.Biogenetically,both 1 and2 were proposed to derive from 3,3',4,5,5'-pentahydroxy stilbene and could be generated through key inverse-electron-demand[4+2]and[5+2]cycloadditions,respectively.Interestingly,both(±)-1 and(±)-2 showed significant inhibition againstα-glucosidase.(±)-1 and its pure enantiomers could modulate protein tyrosine phosphatase-1B(PTP1B)enzyme activities and increased glucose consumption in HepG2 cells in a dose-dependent manner.展开更多
Two new stilbenoids, cis-e-viniferin (3) and 2b,14b-dehydro-bisresveratrol (4) were synthesized by photooxida-tion reaction of trans-e-viniferin (2) prepared from trans-resveratrol (1). Pentamethoxyl trans-e-viniferin...Two new stilbenoids, cis-e-viniferin (3) and 2b,14b-dehydro-bisresveratrol (4) were synthesized by photooxida-tion reaction of trans-e-viniferin (2) prepared from trans-resveratrol (1). Pentamethoxyl trans-e-viniferin (5) and pentamethoxyl cis-e-viniferin (6) were also obtained by methylation of trans-e-viniferin (2) with (MeO)2SO2. Their structures were elucidated on the basis of spectral evidence. Compounds 3 and 4 showed potent inhibition of TNF-a at concentrations of 10-5 molL-1 with inhibitory ratios of 51.43% and 36.64%, respectively.展开更多
The objective was to isolate,elucidate and analyze the bioactive chemicals from the tuber of Arundina graminifolia(Dai Monority Medicine).The compounds were extracted by 95%alcohol and isolated by column chromatograph...The objective was to isolate,elucidate and analyze the bioactive chemicals from the tuber of Arundina graminifolia(Dai Monority Medicine).The compounds were extracted by 95%alcohol and isolated by column chromatography on silica gel,Sephedax LH-20 and ODS.The structures were determined by UV,IR,NMR and MS spectra.展开更多
基金financially supported by the CAMS Innovation Fund for Medical Sciences(CIFMS,No.2021-I2M-1-028)。
文摘Two racemic pairs of new stilbenoid dimers,(±)-heterosmilaxones A(1)and B(2),with unique 6/6/6and 6/5/7 tricyclic core systems,respectively,were isolated from the rhizomes of Heterosmilax yunnanensis.Their structures were elucidated through comprehensive spectroscopic analyses,quantum chemical calculations and X-ray diffraction crystallography.Compound(+)-1,initially reported as syagrusin A with a 1,4,4a,9a-tetrahydrofluoren-9-one skeleton,is now revised to a new structure characteristic with a benzo bicyclo[3.3.1]nonene scaffold.And compound 2 bears an unprecedented carbon skeleton with four continuous chiral centers in the central benzo bicyclo[4.2.1]nonene motif.Biogenetically,both 1 and2 were proposed to derive from 3,3',4,5,5'-pentahydroxy stilbene and could be generated through key inverse-electron-demand[4+2]and[5+2]cycloadditions,respectively.Interestingly,both(±)-1 and(±)-2 showed significant inhibition againstα-glucosidase.(±)-1 and its pure enantiomers could modulate protein tyrosine phosphatase-1B(PTP1B)enzyme activities and increased glucose consumption in HepG2 cells in a dose-dependent manner.
基金Project supported by the National Natural Science Foundation of China (No. 30070889).
文摘Two new stilbenoids, cis-e-viniferin (3) and 2b,14b-dehydro-bisresveratrol (4) were synthesized by photooxida-tion reaction of trans-e-viniferin (2) prepared from trans-resveratrol (1). Pentamethoxyl trans-e-viniferin (5) and pentamethoxyl cis-e-viniferin (6) were also obtained by methylation of trans-e-viniferin (2) with (MeO)2SO2. Their structures were elucidated on the basis of spectral evidence. Compounds 3 and 4 showed potent inhibition of TNF-a at concentrations of 10-5 molL-1 with inhibitory ratios of 51.43% and 36.64%, respectively.
基金supported by National Natural Science Foundation of China(No.81473422)the Fundamental Research Funds for the Central Universities(SCUT-2015zz051)
文摘The objective was to isolate,elucidate and analyze the bioactive chemicals from the tuber of Arundina graminifolia(Dai Monority Medicine).The compounds were extracted by 95%alcohol and isolated by column chromatography on silica gel,Sephedax LH-20 and ODS.The structures were determined by UV,IR,NMR and MS spectra.
