Study on the regulatory effect of liver X receptor in HEK293 cells by six main diterpene esters in Semen Euphorbiae

Background:To study the effects of the main diterpene esters in Euphorbia factor L_(1),L_(2),L_(3),L_(7a),L_(7b)and L_(8)on the transcriptional activity and protein expression of liver X receptor(LXR).Methods:The effect of the main diterpene ester components in Semen Euphorbiae on the viability of HEK293 cells were studied by MTT assay.The LXR-Luc plasmid vector was transfected into HEK293 cells and treated with Euphorbia factor L_(1),L_(2),L_(3),L_(7a),L_(7b)and L_(8)for 24 h.The effect of the main diterpene ester components of Semen Euphorbiae on LXR-Luc luciferase activity was investigated by dual luciferase reporter gene system,and the expression of LXRαprotein was detected by Western Blot.Results:Euphorbia factor L_(1),L_(2),L_(3),L_(7a),L_(7b)and L_(8)could significantly reduce the relative luciferase activity(RLU)of LXRα,and the expression level of LXRαprotein was significantly down-regulated.Conclusion:Euphorbia factor L_(1),L_(2),L_(3),L_(7a),L_(7b)and L_(8)can inhibit the expression of LXR protein level,which may be achieved by inhibiting the transcriptional activity of LXR.

Two Novel Myrinsol Diterpenes from Euphorbia prolifera

Two novel diterpenes, Euphorprolitherin A (1) and Euphorprolitherin B (2), were isolated from the roots of Euphorbia prolifera. Their structures were elucidated on the basis of spectroscopic methods.

Crystal Structure of a New Cembranolide Diterpene

A new cembranoide deterpene was isolated from the soft coral Sinularia Tenella . The crystal and chemical structure of the title compound were determined by means of spectroscopic methods and X ray diffraction analysis as ( 1R *,4R *,5S *,12S *,12R * ) 9 acetoxy cembr 8\%E\%,15(17) dien 16,4 olide. It shows a moderate cytotoxicity against P 388 and L 1210 cell lines.

Two new antitumor diterpenes from Pinus sylvestris

Two new diterpenes, 15-ethyl-18-methyl pinifolate （1） and 18-hydroxy-labda-8（17）, 13E-dien-15-acetate （2）, were isolated from the needles of Pinus sylvestris. Their structures were elucidated by spectroscopic methods, including 2D-NMR spectra. Compound 1 exhibited the significant cytotoxic activity against the human carcinoma cell lines Hela, SK-N-SH and BEL-7402 in vitro.

One New Diterpene Glucoside from the Roots of Rhododendron molle

One new grayanane diterpene glucoside, rhodomoside A 1 was isolated from the roots of Rhododendron molle G. Don (Ericaceae). Its structure was elucidated on the basis of spectral analysis.

Two new diterpene alkaloids from Delphinium chrysotrichum

Chemical investigation on the ethanol extract from the whole plants of Delphinium chrysotrichum resulted in the isolation of two new diterpene alkaloids named delphatisine A （1） and delphatisine B （2）, respectively. The structures of the new compounds were deduced on the basis of their spectral data （IR, HREIMS, EIMS, 1 D, 2D-NMR）. This is the first report on the isolation of diterpenoid alkaloids from the D. chrysotrichum.

A New Isopimarane Diterpene from Nepeta prattii

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).

Characterization of phloroglucinol derivatives and diterpenes in Euphorbia ebracteolata Hayata by utilizing ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry

Euphorbia ebracteolata Hayata （E. ebracteolata） is a Chinese herbal medicine used for the treatment of tumor diseases. An ultra-performance liquid chromatography/quadrupole time-of-flight mass spectrometry （UPLC-Q-TOF/MS） based chemical profiling approach was established for the rapid separation and characterization on phloroglucinol derivatives and diterpenes in E. ebracteolata. Three phloroglucinol derivatives and nine diterpenes were identified by exact mass measurement and were further confirmed by Ms2 data. In addition, the chemical profiles of six compounds were acquired by reference standards. Furthermore, the fragmentation rules of phloroglucinol derivatives and diterpenes of E. ebracteolata were analyzed, and each chromatographic peak was classified.

Two New Diterpene Alkaloids from the Roots of Spiraea japonica var.Acuta

Chemical investigation on the ethanol extract from the roots of Spiraea japonica var. acuta resulted in the isolation of two new diterpene alkaloids named spiratines A and B (1-2), respectively.

Tangutidines A-C,Three Amphoteric Diterpene Alkaloids from Aconitum tanguticum

Three new diterpene alkaloids,tangutidines A-C(1-3),and four known alkaloids(4-7)were isolated from the whole plant of Aconitum tanguticum,from which amphoteric diterpene alkaloids(1-3)were obtained for the first time.The structures of 1-3 were elucidated by detailed interpretation of spectroscopic data,including MS and NMR data.All of them were evaluated for their cytotoxic activities.

Isolation and Crystal Structure of Ent-kaurane Diterpenes from Rubus corchorifolius L. f.

In this study, ent-Kaurane-3β,16β,17-trioi （1） and ent-kaurane-2a,16β,17-triol （2）, were isolated from the leaves ofRubus corchorifolius L. f. Their structures were elucidated based on extensive spectroscopic analysis. NMR experiments identified the two compounds and X-ray crystallographic analysis confirmed their crystal structures. The crystal of 1 belongs to monoclinic with space group P21 and a = 10.7641（3）, b = 7.2789（3）, c = 11.7862（4） A, β = 95.275（3）°, V = 919.55（6） A3, Z = 2, C20H34O4, Mr = 322.49 g/mol, Dc = 1.230 g/m3, F（000） = 376, 2 = 1.54178 A,μ = 0.661 mm-1, R = 0.0319, and wR = 0.0811 for 10889 observed reflections （I〉 2σ（I））. The crystal of 2 is classified as orthorhombic with space group P212121 and a = 10.7641（3）, b = 12.72224（19）, c = 21.3929（3） A, V= 1748.94（4） A3, Z= 4, C20H3404, Mr = 322.47, De = 1.225 Mg/m3 F（000） = 712, λ = 1.54184 A,μ = 0.625 mm-1, R = 0.0303 and wR = 0.0759 for 10470 observed reflections （1〉 2σ（I））. Meanwhile, the compound revealed low inhibitory activities toward HepG2, MCF-7, and SCG-7901 cells.

FIVE NEW DITERPENES FROM EUPHORBIA SIEBOLDIANA

Five new diterpenes were isolated from Euphorbia sieboldiana and identified as atis-16-en-13(S)-hydroxy-3,14-dione(Ⅰ),atis-16-en- 14-oxo-13(S),3 β-diol(Ⅱ),atisane-3-oxo-16α,17-diol(Ⅳ),atisane-3β ,16α,17-triol(Ⅴ)and atisane-3β-acetyl-16α,17-diol(Ⅵ)based on the chemical,spectral evidences and X-ray diffraction.

SWINANINE C＆D，TWO NEW DITERPENE ALKALOIDS FROM DELPHINIUM SWINANENSE VAR LEPTOPOGON

s: Two new diterpene alkaloids named swinanine C and D were isolated from Delphinium swinanense var leptopogon (H. -M. ) W. T. Wang. Their structures were elucidated by means of spectral methods , principally 1H-NHR, DEPT and 13CNMR techniques.

Studies on Antibacterial QSAR of Diterpene Quinones from Sclvic Przewalskii Maxim

The antibacierial (staphylococcus aureus) activities of 23 diterpene quinones from the Salvia przewalskii Maxim, the artificial synthesis ones and that of the metabolism in pigs were examined in an effort to study the quantitative structure activity relationship with the Free-Wilson method. With the application of the multipiy regression, the Free-Wilson pattern was established by the dummy (indicator) variable of the structural fragments or substituents. The results showed: (1) The diketone moiety played the fundamental role in antibacterial activities, ortho-quinones was higher active than para-quinones. (2) The single bond existed between the C15 and the C16 at D-ring led to higher activity. (3) The saturation at the A-ring led to higher activity. (4) The components adjacent to nitrogen substituents at C15 led to higher activity. (5)The hydroxylation or dehydrogenation at A-ring led to less activity. The research results can provide the theoretical basis for developing a new antibacterial drug from the Salvia diterpene quinones.

Two New Diterpene Acetylxylosides from Aster veitchianus

Two new acetylxylosides, ent-manool-13-O-β-D-2'-acetylxylopyranoside (1) and ent-manool-13-O-β-D-2', 4'-diacetylxylopyranoside (2) were isolated from Aster veitchianus. Their structures were elucidated by spectroscopic methods.