Deoxyandrographolide-19beta-D-Glucoside from the Leaves of Andrographis paniculata.

A new diterpene glucoside has been isolated from the leaves of ANDROGRAPHIS PANICULATA and its structure elucidated as deoxyandrographolide-19beta-D-glucoside on the basis of chemical and spectral evidence. A detailed proton magnetic resonance study of the diterpene was crucial in the structure determination.     

Investigation of the diterpene alkaloids of Aconitum species native to the Carpathian Basin

Aconitum species accumulate highly toxic diterpene alkaloids, which have attracted considerable interest because of their complex structure, interesting chemistry and noteworthy physiological effects. The authors carried out phytochemical analysis of two Aconitum species native to the Carpathian Basin, aiming the isolation of diterpene alkaloids. The multistep chromatographic purification of the extracts of A. vulparia whole plant and A. toxicum root resulted in the isolation of 16 alkaloids. Structure elucidation by means of spectroscopic investigations revealed the presence of 3 (acovulparine, vulparine, acotoxinine) new and 13 already known compounds (anthranoyllycoctonine, delectinine, delcosine, finetiadine, lycoctonine, N-methyl-N-deethyllycocotine, septentriodine, aconitine, aconosine, dolaconine, neoline, songorine, songo-ramine). Alkaloids isolated from A. vulparia are C19 diterpene alkaloids possessing aconitane skeleton, whilst from A. toxicum two C20 diterpene alkaloids with napelline and five diterpene alkaloids with aconitane skeleton were identified. The pharmacological testing of the majority of the isolated compounds has not been reported in the literature yet. Since some of the diterpene alkaloids are structurally very similar to compounds which were active in different in vitro or in vivo experiments, the pharmacological testing of the alkaloids reported in this article seems to be reasonable. The investigation of the compounds may help to reveal structure-activity relationships as well.     

A new cytotoxic acyclic diterpene fromCarpesium divaricatum

A new acyclic diterpene (1) and a known acyclic diterpene, 12(S)-hydroxygeranylgeraniol (2) were isolated from the aerial parts of Carpesium divaricatum. The structure of 1 was determined to be (2E,10E)-1,12-dihydroxy-18-acetoxy-3,7,15-trimethylhexadeca- 2,10,14-triene (1) on the basis of spectroscopic studies. Compounds 1 and 2 exhibited cytotoxicity against cultured human tumor cell lines, A549, SK-OV-3, SK-MEL-2, XF498, and HCT15, with ED50 values ranging from 4.3-10.2 micrograms/ml and 4.1-8.3 micrograms/ml, respectively.     

A new diterpene from the processed roots of Euphorbia Kansui

A new diterpene has been isolated from the processed roots of Euphorbia Kansui. By means of physico-chemical evidences and spectral analysis, the structure was identified as 4-O-acetyl-5-O-benzoyl-3beta-hydroxy-20-deoxyingenol (1).     

A new diterpene from the processed roots of Euphorbia Kansui

A new diterpene has been isolated from the processed roots of Euphorbia Kansui. By means of physico-chemical evidences and spectral analysis, the structure was identified as 4-O-acetyl-5-O-benzoyl-3β-hydroxy-20-deoxyingenol (1).     

昆明山海棠化学成分的研究

从昆明山海棠(Tripterygium hypoglaucum (Lévl) Hutch)茎中分得一单体,经光谱UV,IR,MS,¹H-NMR,¹³C-NMR和2D-NMR)分析,推定为一新成分,命名为雷酚二萜酸(triptonoditerpenic acid).     

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

从毛茛科乌头属植物吉林乌头（ＡｃｏｎｉｔｕｍｋｉｒｉｎｉｎｅＮａｋａｉ）中分得两个Ｃ２０二萜生物碱ｌｅｐｅｎｉｎｅ（雷乌宁）和ｋｉｒｉｎｉｎｅＡ（吉乌碱甲），用化学和波谱方法鉴定了它们的结构，其中后者为新化合物。     

Cloning of the gene cluster responsible for the biosynthesis of brasilicardin A, a unique diterpenoid

Brasilicardin A (BCA), produced by Nocardia brasiliensis IFM 0406 (currently referred to as N. terpenica), has a unique structure consisting of a diterpene skeleton with L-rhamnose, N-acetylglucosamine, amino acid, and 3-hydroxybenzoate moieties, and exhibits potent biological activities. To understand the biosynthetic machinery of this unique compound, we have cloned the corresponding gene cluster. Firstly, we cloned a gene by PCR that encodes geranylgeranyl diphosphate synthase (GGPPS), which produces a direct precursor of diterpene compounds. We obtained four candidate genes and one of the genes was confirmed to encode a GGPPS. By sequence analysis of regions flanking the GGPPS gene, we identified eleven genes (bra1-11), all oriented in the same direction. We did not, however, detect any genes related to L-rhamnose and N-acetylglucosamine biosyntheses in the flanking regions. A gene disruption experiment did indeed show that this gene cluster was responsible for BCA biosynthesis.     

A new diterpene from the processed roots of Euphorbia Kansui

A new diterpene has been isolated from the processed roots of Euphorbia Kansui. By means of physico-chemical evidences and spectral analysis, the structure was identified as 4-O-acetyl-5-O-benzoyl-3β-hydroxy-20-deoxyingenol (1).     

New 6(17)-epoxylathyrane diterpene: aellinane from Euphorbia aellenii induces apoptosis via mitochondrial pathway in ovarian cancer cell line

Euphorbia species have been used in traditional medicine in many countries for the treatment of cancer. This article aims to evaluate the capability of a new lathyrane diterpene isolated from Euphorbia aellenii to induce apoptosis in the Caov-4 cell line to determine the underlying mechanism of its anticancer effects. A new 6(17)-epoxylathyrane diterpenes: aellinane from Euphorbia aellenii was evaluated for viability of Caov-4 cells by MTT method. Apoptosis induction by lathyrane diterpene was confirmed by annexin V-FITC/PI staining, and caspase-6 activation. The Bcl2 and Bax protein content were detected by Western blot analysis. Finally, we employed the fluorescent ROS detection kit and fluorochrome JC-1 to determine ROS levels and loss of mitochondria membrane potential (ΔΨm) in Caov-4 cells, respectively. The results show that lathyrane diterpene has significant cytotoxic effect against Caov-4 cells. The IC50 value was 45?μM. Annexin V/propidium iodide (PI) staining and caspase-6 activity assay confirmed that lathyrane diterpene is able to induce apoptosis in Caov-4 cells. The results also demonstrate that lathyrane diterpene up-regulated Bax and down-regulated Bcl-2 proteins. Moreover, apoptotic effect of lathyrane diterpene was also related to ROS production and loss of mitochondrial membrane potential (ΔΨm). This study demonstrated that lathyrane diterpene has profound activity against Caov-4 cells. Analysis of apoptosis-related proteins revealed that lathyrane diterpene triggered the mitochondrion-mediated apoptosis pathway, which led to the loss of mitochondrial membrane potential (ΔΨm) and activation of caspase-6. Therefore, we believe that lathyrane diterpene might be a promising natural compound in ovarian cancer therapy.     

Diterpene glycosides from Aster homochlamydeus

A new diterpene glycoside 1 was isolated from the whole plant of Aster homochlamydeus Hand-mazz (Compositae), along with four known diterpene glycosides 2-5. Their structures were elucidated by spectroscopic methods, MS, IR, NMR and X-raycrystallographic analyisis. Antibacterial activity of compounds 1-5 was observed.     

A new labdane diterpene from Leonurus heterophyllus

A new labdane diterpene, heteronone B (1), together with a known labdane diterpene, heteronone A (2), have been isolated from the aerial part of Leonurus heterophyllus. Their structures were established mainly by 1D and 2D NMR analysis and the stereochemistry of 2 was confirmed by single-crystal X-ray diffraction analysis.     

Kappa-opioid receptor-mediated effects of the plant-derived hallucinogen, salvinorin A, on inverted screen performance in the mouse

Salvinorin A is a pharmacologically active diterpene that occurs naturally in the Mexican mint Ska Maria Pastora (Salvia divinorum) and represents the first naturally occurring kappa-opioid receptor agonist. The chemical structure of salvinorin A is novel among the opioids, and thus defines a new structural class of kappa-opioid-receptor selective drugs. Few studies have examined the effects of salvinorin A in vivo, and fewer still have attempted to assess the agonist actions of this compound at mu-opioid, delta-opioid, and kappa-opioid receptors using selective antagonists. In the mouse, salvinorin A disrupted climbing behavior on an inverted screen task, indicating a rapid, but short-lived induction of sedation/motor incoordination. Similar effects were observed with the mu-agonist remifentanil and the synthetic kappa-agonist U69,593. When behaviorally equivalent doses of all three opioids were challenged with antagonists at doses selective for mu-opioid, delta-opioid, or kappa-opioid receptors, results suggested that the motoric effects of remifentanil were mediated by mu-receptors, whereas those of salvinorin A and U69,593 were mediated via kappa-receptors. Despite similar potencies and degrees of effectiveness, salvinorin A and U69,593 differed with regard to their susceptibility to antagonism by the kappa-antagonist nor-binaltorphamine. This later finding, coupled with the novel chemical structure of the compound, is consistent with recent findings that the diterpene salvinorin A may bind to the kappa-receptor in a manner that is qualitatively different from that of more traditional kappa-agonists such as the benzeneacetamide U69,593. Such pharmacological differences among these kappa-opioids raise the possibility that the development of other diterpene-based opioids may yield important therapeutic compounds.     

二萜合酶的研究进展

植物二萜类化合物广泛存在于自然界中,是一类重要的天然化合物。随着一些具有重要经济价值的二萜不断被发现,其生物合成中的二萜合酶也倍受关注。二萜合酶催化活性的多样性决定了终产物(二萜化合物)的丰富性。本文重点探讨了近年来二萜生物合成途径和二萜合酶的类型、克隆、催化机制及其合成生物学应用等研究进展。     

ent-trachyloban-3beta-ol,a new cytotoxic diterpene from Croton zambesicus

The dichloromethane extract of leaves of Croton zambesicus (Euphorbiaceae) showing in vitro cytotoxicity against human cervix carcinoma cells was investigated in order to identify its active compounds. A bio-guided fractionation by HSCCC followed by MPLC led us to isolate a trachylobane diterpene, ent-trachyloban-3beta-ol, with cytotoxic properties (IC50 on HeLa cells = 7.3 microg/ml). This is the first report on the cytotoxicity of a trachylobane diterpene.     

筋骨草属植物中新克罗烷型二萜类成分的核磁共振谱图特征

唇形科筋骨草属（Ajuga）植物具有广泛的药用价值,其中新克罗烷型二萜类成分是其主要的活性成分,本文将对筋骨草属植物中分离得到的新克罗烷型二萜成分的核磁共振波谱特征进行综述,为该类成分在结构鉴定方面提供文献资料。     

A novel antibacterial diterpene from Premna schimperi

A novel diterpene, (5R, 8R, 9S, 10R)-12-oxo-ent-3,13(16)-clerodien-15-oic acid, has been obtained from the leaves of Premna schimperi (Verbenaceae) using an anti-microbial bioassay-guided isolation procedure. The diterpene was identified on the basis of spectroscopic data and is active against the Gram-positive bacteria Staphylococcus aureus and Bacillus subtilis in the concentration range 20-25 micrograms ml-1.     

3-Oxo-axisonitrile-3, a new sesquiterpene isocyanide from the Chinese marine sponge Acanthella sp

A new sesquiterpene isocyanide, 3-oxo-axisonitrile-3 (1), with a spiro [5,6] decane skeleton (spiroaxane) together with a known related sesquiterpene isonitrile (2), sesquiterpene isothiocyanates (3-8) and two diterpene isonitriles (9, 10) have been isolated from the Chinese marine sponge Acanthella sp. The structure of 1 has been determined on the basis of spectroscopic analysis.     

Research on African Medicinal Plants. XI1 8-Hydroxycolumbin, A New Furanoid Diterpene from Chasmanthera dependens.

A new furanoid diterpene, 8-hydroxycolumbin, 2, was isolated from the bark of CHASMANTHERA DEPENDENS.     

Myrocin C, a new diterpene antitumor antibiotic from Myrothecium verrucaria. II. Physico-chemical properties and structure determination

The structure of a new antitumor antibiotic, myrocin C, from a strain of Myrothecium verrucaria was characterized as a pentacyclic pimarane diterpene composed of a gamma-lactol group and a unique cyclopropane ring on the basis of its physico-chemical properties and spectroscopic data as well as a single-crystal X-ray diffraction analysis of its monoacetyl derivative.