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.

A Bioactive Diterpene from the Chinese Herb Aster souliei

Aster souliei Franch, (Compositae) is a. herbaceous plant distributed innorth China. It has been used in folk medicine as antipyretic, detoxicant, expectorant andantitussive. In an effort to find biologically active components from Chinese medicinal plants ' ,we have examined the aerial parts of this herb, leading to the isolation of a clerodane-typediterpene, 18, 19-dihydroxy-5α, 10β-neo-cleroda-3, 13 (l4)-dien-16, 15-butenolide (1). In thispaper we report the structural elucidation, and the antitumor and antibacterial activities of thiscompound. It was found that 1 possesses moderate cytotoxicity against human leukemia cells (HL-60)and activity against microorganisms.

Kiridine, A C18-Diterpene Alkaloid from Aconitum kirinense

Kiridine, a new C18-diterpenoid alkaloid, was isolated from the roots of Aconitum kirinense. Its structure was elucidated by MS, 1D- and 2D- NMR, and mono-crystal X-ray analysis. It is the first norditerpene alkaloid containing a 9,14-methylenedioxy group and the substituent at C-14 is (-configuration.

An Abietane Diterpene and a Sterol from Fungus Phellinus igniarius

A new abietane diterpene 12-hydroxy-7-oxo-5, 8, 11, 13-tetraene-18, 6-abietanolide, together with a new natural sterol stigmasta-7, 22-diene-3β, 5α 6α-triol have been isolated from the fruiting body of the fungus Phellinus igniarius. Their structures were elucidated by spectroscopic methods including 2D NMR techniques.

Diterpene Alkaloids of Aconitum kirinense Nakai I.Lepe-nine and Kirinine A

wo diterpene alkaloids, lepenine and kirinine A were isolated for the first time from the roots of Aconitum kirinense Nakai. Their structures have been established by IR, HRMS, NMR analysis and chemical reactions, and kininine A was found to be a new C 20 diterpene alkaloid.

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.

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 (Ericaccae). Its structure was elucidated on the basis of spectral analysis.

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.

A New Diterpene Acid from the Flowers of Heteropappus altaicus

A new compound, named heteraltaic acid was isolated from the flowers of Heteropappus altaicus (willd) Novopokr.. The compound was elucidated as (5R, 6S, 8aS) –5- [2-(3-furyl ) ethyl-5, 6, 8a-trimethyl-4a, 5, 6, 7, 8, 8a -hexahydro-1-naphthalenecarboxylic acid] by the combination of 1D and 2D NMR techniques (HSQC, HMBC) and X-ray analysis.

A new lathyrane diterpene glycoside from Euphorbia helioscopia L.

A new lathyrane diterpene glycoside,named 3β,7β,15β-trihydroxy-14-oxolathyra-5E,12E-dienyl-16-O-β-D-glucopyranoside, was isolated from Euphorbia helioscopia L.Its structure was established by spectroscopic techniques including 2D NMR.

Structural elucidation of a new cembranoid diterpene from the Chinese soft coral Sarcophyton sp.

To investigate the cembranoid diterpenes from the soft coral Sarcophyton sp. collected in the South China Sea. Repeatedly column chromatography was performed for the isolation and purification. The structures were elucidated on the basis of extensive spectral data （IR, MS, 1 D- and 2D-NMR） analysis by comparing with literature data. A new cembranoid diterpene namely sarcophyolide A （1）, together with 7a, 8β-dihydroxydeepoxysarcophine （2） were isolated from this species. The cembranoid diterpenes with 7-1actone could be chemotaxonomic markers of Sarcophyton sp.

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.

Chlorophytoside A, a New Labdane Diterpene Glycoside from Chlorophytum laxum

A new labdane-type diterpene glycoside 1 , chlorophytoside A, had been isolated from Chlorophytum laxum R.Br. The structure had been elucidated as (10S)-6α-hydroxy- labda-8,13-dien-15,16-olide 3R-O-β-D-glucopyranoside on the basis of chemical and spectroscopic data.

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.

A New Daphnane Diterpene from Daphne tangutica

A new daphnane diterpene was isolated from the root barks of Daphne tangutica Maxim. Its structure was elucidated as 1, 2α-dihydro-20-palimoyldaphnctoxin by the spectroscopic evidence including 2D-NMR.

A New Diterpene from Suregada glomerulate(Blume) Baill

A new diterpene with an abietane skeleton, 3β-hydroxy-8α,14α-epoxyabieta-11,13(15)- dien-16,12-olide, was isolated from the root of Suregada glomerulate(Blume) Baill. Its structure was elucidated on the basis of spectroscopic and X-ray crystallographic analysis.

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.