A facile ndxture of the C-11 isomeric 3 - oxo-7αH-eudes ma-4-en- 9β, 1 2-diol has been achieved ffom oxycarvone. The C-11 configuration of natural product is established through comparison of IHNMR spectra between ...A facile ndxture of the C-11 isomeric 3 - oxo-7αH-eudes ma-4-en- 9β, 1 2-diol has been achieved ffom oxycarvone. The C-11 configuration of natural product is established through comparison of IHNMR spectra between synthatic 1b, or the mixture of 1a and 1b, and natural diol.展开更多
2β,3α--Dihydroxyurs-12-en-28-oic acid （6） is a naturally occurring diastereoisomer of corosolic acid with glycogen phosphorylase inhibitory activity. A new strategy for the semi-synthesis of 6 was developed. Using...2β,3α--Dihydroxyurs-12-en-28-oic acid （6） is a naturally occurring diastereoisomer of corosolic acid with glycogen phosphorylase inhibitory activity. A new strategy for the semi-synthesis of 6 was developed. Using the commercially available ursolic acid （1） as the starting materials, 6 was synthesized through five facile reactions with a high stereoselectivity and an overall yield of 47,3%, The structure of 6 was confirmed by optical rotation, ESI-MS, 1H NMR and 13C NMR data,展开更多
From the fruit of Rosa davidii Crep., eleven compounds were isolated and identified by spectral evidence, viz. 2 alpha, 3 beta, 19 beta -trihydroxyl-olean-12-en-28-oic acid (1), 2 alpha, 3 beta -dihydroxyl-urs-28 (13)...From the fruit of Rosa davidii Crep., eleven compounds were isolated and identified by spectral evidence, viz. 2 alpha, 3 beta, 19 beta -trihydroxyl-olean-12-en-28-oic acid (1), 2 alpha, 3 beta -dihydroxyl-urs-28 (13)-lactone (2), arjunic acid (3), euscaphic acid (4), 2 alpha, 3 beta -dihydroxyl-urs-12-en-28-oic acid (5), oleanolic acid (6), kaempferol (7), tiliroside (8), quercetin (9), daucosterol (10) and beta -sitosterol (11). Among them, 1 and 2 were new compounds.展开更多
Two new pentacyclic triterpene acids, 1a, 3b-dihydroxyl-olean-12-en-28-oic acid and 1a, 2a, 3b-trihydroxyl-olean-12-en-28-oic acid, were isolated from the arial parts of Sabia parviflora.
A new oleanane-type triterpene was isolated from the roots of Doellingeria scaber. Its structure was identified as 3-oxo-16a-hydroxy-olean-12-en-28-oic acid based on 1D and 2D NMR spectroscopy and X-ray analysis.
Two new triterpenes, 2α,3β-dihydroxyurs- 12-en- 18,19-epoxy-28-oic acid （1） and 18,19-seco, 2α, 2α-dihydroxyl-19-oxo-urs- 11,13（18）-dien-28-oic acid （2） were isolated from the herbaceous part of Duchesnea in...Two new triterpenes, 2α,3β-dihydroxyurs- 12-en- 18,19-epoxy-28-oic acid （1） and 18,19-seco, 2α, 2α-dihydroxyl-19-oxo-urs- 11,13（18）-dien-28-oic acid （2） were isolated from the herbaceous part of Duchesnea indica. Their structures were elucidated by spectroscopic analysis, including 2D NMR technique. The isolated compounds exhibited moderate cytotoxic activities against HeLa and L929 cell lines.展开更多
Urease enzyme(UE)has been reported to be a potent virulence factor for Helicobacter pylori(HP)bacteria indicated to be responsible for various gastrointestinal diseases.Therefore,the spread of HP,currently regarded by...Urease enzyme(UE)has been reported to be a potent virulence factor for Helicobacter pylori(HP)bacteria indicated to be responsible for various gastrointestinal diseases.Therefore,the spread of HP,currently regarded by the World Health Organization as a class 1 carcinogen,could be better controlled by targeting UE.It is in this line that we have synthesized three new derivatives(2–4)of the naturally occurring olean-12-en-3-one(1),which was previously isolated from the figs of Ficus vallis-choudae Delile(Moraceae).Among the synthesized compounds,3 and 4 contain an indole moiety.Their structures were unambiguously assigned by spectroscopic and spectrometric techniques(1D-NMR,2D-NMR and MS).The starting material and the synthesized compounds were screened for UE inhibition activity,and showed significant activities with IC50 values ranging from 14.5 to 24.6 lM,with compound(1)being the most potent as compared to the positive control thiourea(IC50=21.6 lM).Amongst the synthetic derivatives,compound 4 was the most potent(IC50-=17.9 lM),while the others showed activities close to that of the control.In addition,molecular docking study of target compounds 2–4 was performed in an attempt to explore their binding mode for the design of more potent UE inhibitors.展开更多
As a part of our interest in biologically active germacranolides from the genus Carpesium （Compositae）, we have investigated the constituents of Carpesium cernuum. This paper reports the isolation and structural elu...As a part of our interest in biologically active germacranolides from the genus Carpesium （Compositae）, we have investigated the constituents of Carpesium cernuum. This paper reports the isolation and structural elucidation of a new germacranolide, cernolide A （Compound 1）, from the herb. The structure of Compound 1 was determined as 2α,3β-dihydroxy-9-angeloxygermacra-4-en-6,12-olide on the basis of spectral evidence. The skeleton of Compound 1 was elucidation by IR, MS, ^1H and ^13C NMR, COSY, HMQC and HMBC experiments. The stereochemistry of Compound 1 was deduced by ROESY spectral data. Finally, the procedures of extraction and isolation were described in detail.展开更多
文摘A facile ndxture of the C-11 isomeric 3 - oxo-7αH-eudes ma-4-en- 9β, 1 2-diol has been achieved ffom oxycarvone. The C-11 configuration of natural product is established through comparison of IHNMR spectra between synthatic 1b, or the mixture of 1a and 1b, and natural diol.
基金Financial support from the Fundamental Research Funds for the Central Universities(No.DUT12JB08)
文摘2β,3α--Dihydroxyurs-12-en-28-oic acid （6） is a naturally occurring diastereoisomer of corosolic acid with glycogen phosphorylase inhibitory activity. A new strategy for the semi-synthesis of 6 was developed. Using the commercially available ursolic acid （1） as the starting materials, 6 was synthesized through five facile reactions with a high stereoselectivity and an overall yield of 47,3%, The structure of 6 was confirmed by optical rotation, ESI-MS, 1H NMR and 13C NMR data,
文摘利用硅胶柱色谱反复层析从黄背越橘的乙酸乙酯部分分得7个化合物,根据理化性质和光谱数据鉴定,分别为β-谷甾醇(β-sitosterol,Ⅰ),熊果酸(ursolic acid,Ⅱ),蒲公英萜醇(taraxerol,Ⅲ),蒲公英萜酮(taraxerone,Ⅳ),木栓酮(friedelin,Ⅴ),木栓醇(friedelinol,Ⅵ),19,24-d ihydroxyurs-12-en-3-one-28-oic ac id(Ⅶ).
文摘Two new pentacyclic triterpene acids, 1a, 3b-dihydroxyl-olean-12-en-28-oic acid and 1a, 2a, 3b-trihydroxyl-olean-12-en-28-oic acid, were isolated from the arial parts of Sabia parviflora.
文摘A new oleanane-type triterpene was isolated from the roots of Doellingeria scaber. Its structure was identified as 3-oxo-16a-hydroxy-olean-12-en-28-oic acid based on 1D and 2D NMR spectroscopy and X-ray analysis.
基金sponsored by the Scientific Research Foundation of Tianjin Medical University,Tianjin,China.
文摘Two new triterpenes, 2α,3β-dihydroxyurs- 12-en- 18,19-epoxy-28-oic acid （1） and 18,19-seco, 2α, 2α-dihydroxyl-19-oxo-urs- 11,13（18）-dien-28-oic acid （2） were isolated from the herbaceous part of Duchesnea indica. Their structures were elucidated by spectroscopic analysis, including 2D NMR technique. The isolated compounds exhibited moderate cytotoxic activities against HeLa and L929 cell lines.
基金BKJJ acknowledges The World Academy of Sciences(TWAS)and the International Center for Chemical and Biological Sciences(ICCBS),University of Karachi,Pakistan for their financial and technical support through the ICCBS-TWAS Postdoctoral Fellowship number 3240280476CVS also acknowl-edges financial support from the German Academic Exchange Ser-vices(DAAD)for doctoral candidates.
文摘Urease enzyme(UE)has been reported to be a potent virulence factor for Helicobacter pylori(HP)bacteria indicated to be responsible for various gastrointestinal diseases.Therefore,the spread of HP,currently regarded by the World Health Organization as a class 1 carcinogen,could be better controlled by targeting UE.It is in this line that we have synthesized three new derivatives(2–4)of the naturally occurring olean-12-en-3-one(1),which was previously isolated from the figs of Ficus vallis-choudae Delile(Moraceae).Among the synthesized compounds,3 and 4 contain an indole moiety.Their structures were unambiguously assigned by spectroscopic and spectrometric techniques(1D-NMR,2D-NMR and MS).The starting material and the synthesized compounds were screened for UE inhibition activity,and showed significant activities with IC50 values ranging from 14.5 to 24.6 lM,with compound(1)being the most potent as compared to the positive control thiourea(IC50=21.6 lM).Amongst the synthetic derivatives,compound 4 was the most potent(IC50-=17.9 lM),while the others showed activities close to that of the control.In addition,molecular docking study of target compounds 2–4 was performed in an attempt to explore their binding mode for the design of more potent UE inhibitors.
文摘As a part of our interest in biologically active germacranolides from the genus Carpesium （Compositae）, we have investigated the constituents of Carpesium cernuum. This paper reports the isolation and structural elucidation of a new germacranolide, cernolide A （Compound 1）, from the herb. The structure of Compound 1 was determined as 2α,3β-dihydroxy-9-angeloxygermacra-4-en-6,12-olide on the basis of spectral evidence. The skeleton of Compound 1 was elucidation by IR, MS, ^1H and ^13C NMR, COSY, HMQC and HMBC experiments. The stereochemistry of Compound 1 was deduced by ROESY spectral data. Finally, the procedures of extraction and isolation were described in detail.
