A new isopimarane diterpene, isopimar-15-en-3 beta,8 beta,20-triol, was isolated from Nepeta prattii. Its structure was elucidated by spectral methods (EIMS, 1D and 2D NMR).
In view of the exploration cases of immature coal-associated hydrocarbons in the world, it can be seen that resinite and exudatinite are important macerals in Huangxian and Baise brown coals on the basis of a random s...In view of the exploration cases of immature coal-associated hydrocarbons in the world, it can be seen that resinite and exudatinite are important macerals in Huangxian and Baise brown coals on the basis of a random sampling investigation from twelve Chinese Tertiary coal-bearing basins, and resin-genetlc compounds, i.e. isopimarane, abietane, simonellite, retene, etc., account for 60% and more of total hydrocarbon fractions in the soluble parts of both the brown coals. Owing to the effect of redox environmental factors during sedimentary and diagenetic phases, the aromaticity of resin-genetic compounds is apparently different in both kinds of brown coals, it probably is one of the important reasons why naphthenic base or aromatic base oils have resulted.展开更多
A new isopimarane-type diterpene （liwariverol, 1） and eight known compounds were isolated and characterized from the EtOAc extract of the whole plant of Potamogeton crispus. The structure of 1 was elucidated to be 1...A new isopimarane-type diterpene （liwariverol, 1） and eight known compounds were isolated and characterized from the EtOAc extract of the whole plant of Potamogeton crispus. The structure of 1 was elucidated to be 17-hydroxy-8c^H-isopimara-9（11）,15- diene by means of spectroscopic methods. Among the isolates, crenulatoside A （2）, an acyclic sesquiterpene glycoside, was found to have anti-oxidative activity with enhancement of the expression of the NAD（P）H：quinone oxidoreductase 1 （NQO1） in human neuroblastoma SH-SY5Y cells at 100 μmol/L after a 24-h incubation.展开更多
A phytochemical investigation was carried out on the extract of a medicinal plant Callicarpa nudiflora,resulting in the characterization of five new 3,4-seco-isopimarane(1-5)and one new 3,4-seco-pimarane diterpenoid(6...A phytochemical investigation was carried out on the extract of a medicinal plant Callicarpa nudiflora,resulting in the characterization of five new 3,4-seco-isopimarane(1-5)and one new 3,4-seco-pimarane diterpenoid(6),together with four known compounds.The structures of the new compounds were fully elucidated by extensive analysis of MS,1 D and 2 D NMR spectroscopic data,and time-dependent density functional theory(TDDFT)calculation of electronic circular dichroism(ECD)spectra,and DFT calculations for NMR chemical shifts and optical rotations.展开更多
文摘A new isopimarane diterpene, isopimar-15-en-3 beta,8 beta,20-triol, was isolated from Nepeta prattii. Its structure was elucidated by spectral methods (EIMS, 1D and 2D NMR).
基金Project was funded by both the Chinese National Scientific Foundationthe Bio- and Gas geochemisiry Laboratary,Lanzhou Institute of Petroleum Geology,Academia Sinica
文摘In view of the exploration cases of immature coal-associated hydrocarbons in the world, it can be seen that resinite and exudatinite are important macerals in Huangxian and Baise brown coals on the basis of a random sampling investigation from twelve Chinese Tertiary coal-bearing basins, and resin-genetlc compounds, i.e. isopimarane, abietane, simonellite, retene, etc., account for 60% and more of total hydrocarbon fractions in the soluble parts of both the brown coals. Owing to the effect of redox environmental factors during sedimentary and diagenetic phases, the aromaticity of resin-genetic compounds is apparently different in both kinds of brown coals, it probably is one of the important reasons why naphthenic base or aromatic base oils have resulted.
基金supported by an NSFC grant(No90713040)STCSM grants(Nos06DZ19002,07DZ22006, and 11DZ1921203)
文摘A new isopimarane-type diterpene （liwariverol, 1） and eight known compounds were isolated and characterized from the EtOAc extract of the whole plant of Potamogeton crispus. The structure of 1 was elucidated to be 17-hydroxy-8c^H-isopimara-9（11）,15- diene by means of spectroscopic methods. Among the isolates, crenulatoside A （2）, an acyclic sesquiterpene glycoside, was found to have anti-oxidative activity with enhancement of the expression of the NAD（P）H：quinone oxidoreductase 1 （NQO1） in human neuroblastoma SH-SY5Y cells at 100 μmol/L after a 24-h incubation.
基金supported from the China National Key R&D Program(Nos.2017YFE0195100 and 2018YFC.707000)the National Natural Science Foundation of China(Nos.21920102003 and 81903485)。
文摘A phytochemical investigation was carried out on the extract of a medicinal plant Callicarpa nudiflora,resulting in the characterization of five new 3,4-seco-isopimarane(1-5)and one new 3,4-seco-pimarane diterpenoid(6),together with four known compounds.The structures of the new compounds were fully elucidated by extensive analysis of MS,1 D and 2 D NMR spectroscopic data,and time-dependent density functional theory(TDDFT)calculation of electronic circular dichroism(ECD)spectra,and DFT calculations for NMR chemical shifts and optical rotations.
