Aqueous ethanol extracts of powdered stems of Dendrobium loddigesii afforded three new phenolics including threo-7-Oethyl-9-O-(4-hydroxyphenyl)propionyl-guaiacylglycerol(1),(R)-4,5,4ʹ-trihydroxy-3,3ʹ,α-trimethoxybibe...Aqueous ethanol extracts of powdered stems of Dendrobium loddigesii afforded three new phenolics including threo-7-Oethyl-9-O-(4-hydroxyphenyl)propionyl-guaiacylglycerol(1),(R)-4,5,4ʹ-trihydroxy-3,3ʹ,α-trimethoxybibenzyl(2)and(S)-5,5′,7-trihydroxy-3′,4′-dimethoxyflavanone(3),together with eleven known analogues.Their structures were determined by extensive spectroscopic analysis.To identify natural antioxidants,whitening,and anti-aging agents,the abilities of these phenolics were assessed to scavenge the 1,2-diphenyl-2-picrylhydrazyl(DPPH)radical,their abilities to inhibit tyrosinase production,and their abilities to stimulate collagen production by human dermal fibroblasts-adult(HDFa)assay.It was found that compounds 1,4-8,13 and 14 exhibited significant DPPH radical scavenging activities,compound 10 exhibited tyrosinase inhibitory activity(IC_(50)37.904μg/mL),and compound 9 showed significant collagen production with an EC_(50)value of 3.182μg/mL.These results suggest that phenolic constituents from D.loddigesii may be candidate antioxidants,skin-whitening and/or anti-aging agents.展开更多
A phytochemical investigation on the stems and rhizomes of Sinomenium acutum led to the isolation of 19 compounds, including three phenanthrenes, six anthraquinones, and ten phenolic derivatives. The structures of the...A phytochemical investigation on the stems and rhizomes of Sinomenium acutum led to the isolation of 19 compounds, including three phenanthrenes, six anthraquinones, and ten phenolic derivatives. The structures of the isolated compounds were elucidated by analysis of the MS and NMR spectroscopic data and comparison with the literature. Compounds 1 and 2 are two new natural products, and their 1H and 13C NMR spectral data were fully assigned for the first time, with the help of2D NMR. All of the isolates were obtained from genus Sinomenium for the first time and the phenanthrene and anthraquinone are the structure type first reported from this genus plants.展开更多
基金This project was supported financially by the Yunnan Provincial Science and Technology Department(Nos.2017ZF003-04,2015HB093 and 2019HA001).Authors are grateful to the staff of the analytical group of the State Key Laboratory of Phytochemistry and Plant Resources in West China,Kunming Institute of Botany,Chinese Academy of Sciences,for measurements of all spectra.
文摘Aqueous ethanol extracts of powdered stems of Dendrobium loddigesii afforded three new phenolics including threo-7-Oethyl-9-O-(4-hydroxyphenyl)propionyl-guaiacylglycerol(1),(R)-4,5,4ʹ-trihydroxy-3,3ʹ,α-trimethoxybibenzyl(2)and(S)-5,5′,7-trihydroxy-3′,4′-dimethoxyflavanone(3),together with eleven known analogues.Their structures were determined by extensive spectroscopic analysis.To identify natural antioxidants,whitening,and anti-aging agents,the abilities of these phenolics were assessed to scavenge the 1,2-diphenyl-2-picrylhydrazyl(DPPH)radical,their abilities to inhibit tyrosinase production,and their abilities to stimulate collagen production by human dermal fibroblasts-adult(HDFa)assay.It was found that compounds 1,4-8,13 and 14 exhibited significant DPPH radical scavenging activities,compound 10 exhibited tyrosinase inhibitory activity(IC_(50)37.904μg/mL),and compound 9 showed significant collagen production with an EC_(50)value of 3.182μg/mL.These results suggest that phenolic constituents from D.loddigesii may be candidate antioxidants,skin-whitening and/or anti-aging agents.
基金National Natural Sciences Foundation of Chin(NS FCGrant Nos.81222051 and 81473106)National Key Technology R&D Program"New Drug Innovation"of China(Gran No s.2012ZX09301002-002-002 and 2012ZX09304-005)
文摘A phytochemical investigation on the stems and rhizomes of Sinomenium acutum led to the isolation of 19 compounds, including three phenanthrenes, six anthraquinones, and ten phenolic derivatives. The structures of the isolated compounds were elucidated by analysis of the MS and NMR spectroscopic data and comparison with the literature. Compounds 1 and 2 are two new natural products, and their 1H and 13C NMR spectral data were fully assigned for the first time, with the help of2D NMR. All of the isolates were obtained from genus Sinomenium for the first time and the phenanthrene and anthraquinone are the structure type first reported from this genus plants.
