A simple and efficient method has been developed;benzil/benzoin undergoes smooth condensation with various substituted aldehyde and ammonium acetate in the presence of potassium dihydrogen phosphate（KH;PO;） under mi...A simple and efficient method has been developed;benzil/benzoin undergoes smooth condensation with various substituted aldehyde and ammonium acetate in the presence of potassium dihydrogen phosphate（KH;PO;） under mild reaction conditions to afford the corresponding trisubstituted imidazole in excellent yields.The method for synthesis of product,the reaction mixture was reflux in ethanol for 40-90 min.The present method is simple,efficient,and cost-effective.展开更多
The asymmetric synthesis of （-）-（4R, 5R）-4-[5-（benzo[1, 3]dioxol-5-yl）-4-hydroxyl-1- （pyridin-2-yl）-4,5-dihydro-lH-pyrazol-3-yl]-benzamide with improved Juliá-Colonna asymmetric epoxidation procedure as k...The asymmetric synthesis of （-）-（4R, 5R）-4-[5-（benzo[1, 3]dioxol-5-yl）-4-hydroxyl-1- （pyridin-2-yl）-4,5-dihydro-lH-pyrazol-3-yl]-benzamide with improved Juliá-Colonna asymmetric epoxidation procedure as key step was described.展开更多
A new benzylisoquinoline alkaloid, 1, 2, 3, 4-tetrahydro-5-hydroxyl-8-methoxyl-2- methyl-4'-methoxyl-benzylisoquinoline, was isolated from the arial parts of Sabia parviflora. Its structure was established on the...A new benzylisoquinoline alkaloid, 1, 2, 3, 4-tetrahydro-5-hydroxyl-8-methoxyl-2- methyl-4'-methoxyl-benzylisoquinoline, was isolated from the arial parts of Sabia parviflora. Its structure was established on the basis of spectral analysis.展开更多
A new bicyclic spiroketone was isolated from the bud of Chrysanthemum indicum L. The chemical structure was elucidated as （1R, 9S, 10S）-10-hydroxyl-8 （2＇, 4＇-diynehexylidene）- 9-isovaleryloxy-2, 7-dioxaspiro [5,...A new bicyclic spiroketone was isolated from the bud of Chrysanthemum indicum L. The chemical structure was elucidated as （1R, 9S, 10S）-10-hydroxyl-8 （2＇, 4＇-diynehexylidene）- 9-isovaleryloxy-2, 7-dioxaspiro [5, 4] decane based on the X-ray crystallography.展开更多
Objective To study the constituents in the twigs and leaves of Rhododendron primulaeflorum. Methods The constituents were separated and purified with chromatographic methods. Their structures were elucidated by spectr...Objective To study the constituents in the twigs and leaves of Rhododendron primulaeflorum. Methods The constituents were separated and purified with chromatographic methods. Their structures were elucidated by spectroscopic methods (1D, 2D NMR, IR, and HR-ESI-MS) and chemical analyses. Results One new phenylpropanol glycoside, 4-hydroxyl-5-methoxyl-phenylpropanol-3-O-β-D-glucopyranoside (1), and its aglycone (2) were successfully isolated from the twigs and leaves of R. primulaeflorum. Conclusion Compound 1 is a new phenylpropanol glycoside. Compounds 1 and 2 are isolated from this plant for the first time.展开更多
文摘A simple and efficient method has been developed;benzil/benzoin undergoes smooth condensation with various substituted aldehyde and ammonium acetate in the presence of potassium dihydrogen phosphate（KH;PO;） under mild reaction conditions to afford the corresponding trisubstituted imidazole in excellent yields.The method for synthesis of product,the reaction mixture was reflux in ethanol for 40-90 min.The present method is simple,efficient,and cost-effective.
基金This work was supported by Chinese National Basic Developing Project(973 project:2004CB518908).
文摘The asymmetric synthesis of （-）-（4R, 5R）-4-[5-（benzo[1, 3]dioxol-5-yl）-4-hydroxyl-1- （pyridin-2-yl）-4,5-dihydro-lH-pyrazol-3-yl]-benzamide with improved Juliá-Colonna asymmetric epoxidation procedure as key step was described.
基金We are greatly indebted to Professor X. H. Hu for his help in identification of the plant material and to Professors B. R. Bai and P. Su for measuring NMR spectra.
文摘A new benzylisoquinoline alkaloid, 1, 2, 3, 4-tetrahydro-5-hydroxyl-8-methoxyl-2- methyl-4'-methoxyl-benzylisoquinoline, was isolated from the arial parts of Sabia parviflora. Its structure was established on the basis of spectral analysis.
文摘A new bicyclic spiroketone was isolated from the bud of Chrysanthemum indicum L. The chemical structure was elucidated as （1R, 9S, 10S）-10-hydroxyl-8 （2＇, 4＇-diynehexylidene）- 9-isovaleryloxy-2, 7-dioxaspiro [5, 4] decane based on the X-ray crystallography.
基金National Natural Science Foundation, China (20872122, 21142004)the New Century Talents Scheme of the Ministry of Education, China(NECT-08-0820)+1 种基金the Fundamental Research Funds for the Central Universities, China (SWJTU2010ZT09)SWJTU Science Research Funds (2008A17)
文摘Objective To study the constituents in the twigs and leaves of Rhododendron primulaeflorum. Methods The constituents were separated and purified with chromatographic methods. Their structures were elucidated by spectroscopic methods (1D, 2D NMR, IR, and HR-ESI-MS) and chemical analyses. Results One new phenylpropanol glycoside, 4-hydroxyl-5-methoxyl-phenylpropanol-3-O-β-D-glucopyranoside (1), and its aglycone (2) were successfully isolated from the twigs and leaves of R. primulaeflorum. Conclusion Compound 1 is a new phenylpropanol glycoside. Compounds 1 and 2 are isolated from this plant for the first time.
