Cembrane diterpenoids from the taiwanese soft coral Sarcophyton stolidotum

Investigation of an EtOAc-soluble extract of the soft coral Sarcophyton stolidotum resulted in the isolation of seven new 14-membered carbocyclic cembranes, sarcostolides A-G (1-7), together with two known cembrane diterpenes, isosarcophytoxide and isosarcophine. The structural elucidation of these metabolites was determined on the basis of spectroscopic analyses, particularly 2D NMR techniques. Sarcostolide E (5) exhibited weak to moderate cytotoxic activity against human WiDr and Daoy tumor cell lines. A biogenetic pathway and relationship for compounds 1-7 was also proposed.     

Cembrane diterpenes from the gorgonian Leptogorgia laxa

The new cembrane diterpenes leptodienone A (2) and leptodienone B (3) and the known compounds lopholide, lophodiol B, lophodione, and lophotoxin (1) have been isolated from the gorgonian Leptogorgia laxa collected in the Gulf of California. The structures of the new metabolites have been established by spectroscopic techniques. The in vitro cytotoxicity of the new compounds has been tested against three human tumor cell lines.     

Hirsutalins A-H, eunicellin-based diterpenoids from the soft coral Cladiella hirsuta

Eight new eunicellin-base diterpenoids, hirsutalins A-H (1-8), were isolated from the soft coral Cladiella hirsuta. Their structures were elucidated by spectroscopic methods, particularly in 1D and 2D NMR experiments. The absolute configuration of 1 was determined by Mosher's method. Compounds 1, 5, and 6 have been shown to exhibit cytotoxicity toward several cancer cell lines. Compounds 2-4 and 8 were found to display significant in vitro anti-inflammatory activity in LPS-stimulated RAW264.7 macrophage cells by inhibiting the expression of the iNOS protein, with compound 2 also effectively reducing the level of COX-2 protein.     

Cembrane diterpenes from the gorgonian Lophogorgia peruana

The chemical study of the gorgonian Lophogorgia peruana collected at the Gulf of California has led to the isolation of the new diterpenes lophodienone (2), lophodiol A (3), lophodiol B (4), 17-acetoxylophotoxin (5), 15,16-epoxylophotoxin (6), 17-acetoxy-15,16-epoxylophotoxin (7), and isoepoxylophodione (8), together with the known compounds lophotoxin (1), rubifolide (9), lopholide (10), deoxylophotoxin (11), and the lophotoxin analogues 12 and 13. The structures of the new metabolites have been established by spectroscopic techniques and chemical correlation. The in vitro cytotoxicity has been tested against three tumor cell lines.     

Further casbane-type diterpenes from the soft coral Sinularia depressa

AIM： To study the minor diterpenes from the soft coral Sinularia depressa. METHOD： The chemical constituents were isolated and purified by various chromatographic techniques, and the chemical structures, including absolute configuration, were established on the basis of detailed analysis of spectroscopic data and by literature comparison with the data of related known compounds. RESULTS： A new casbane-type diterpene, 2-epi-10-hydroxydepressin（1）, was isolated and identified. CONCLUSION： Compound 1 is a new casbane-type diterpene.     

Eunicellin-based diterpenoids, australins A-D, isolated from the soft coral Cladiella australis

The EtOAc extract of a Taiwanese soft coral, Caldiella australis, yielded four new eunicellin-based diterpenoids, australins A-D (1-4). The chemical structures of these metabolites were determined on the basis of extensive spectroscopic (including 1D and 2D NMR) analyses and by comparison of their NMR spectral data with those of related metabolites. Metabolite 2 was found to possess a moderate cytotoxic activity against selected breast and liver cancer cell lines.     

乳香中西松烷型二萜类化合物

目的:研究乳香三氯甲烷提取物中的化学成分及其抗肿瘤活性.方法:利用色谱方法进行分离纯化,通过波谱分析和单晶X射线衍射分析鉴定化合物结构;人白血病HL-60细胞生长抑制实验采用细胞计数法.结果:从乳香中分离得到4个西松烷型二萜,分别为incensole-oxide(1),acetyl incensole-oxide(2),incensole(3),acetyl incensole(4).结论:化合物2和4为首次从该属植物中分离得到;化合物4具有抑制HL-60细胞生长作用,IG_(50)值为(16.3±3.4)μmol·L~(-1).     

Cytotoxic cembrenolide diterpenes from the formosan soft coral lobophytum crassum

A new cytotoxic cembrenolide diterpene, lobocrassolide (1), and a known cytotoxic cembrenolide, lobohedleolide (2), were isolated from the Formosan soft coral Lobophytum crassum. The structure of compound 1 was determined by 1D and 2D spectral analysis.     

Cytotoxic dolabellane diterpenes from the Formosan soft coral Clavularia inflata

Six new cytotoxic dolabellane diterpenes, (1R,12R)-dolabella-4(16),7,10-triene-3,13-dione (1), (1R*,7R*,8S*,12R*)-dolabella-4(16),10-diene-7,8-epoxy- 3,13-dione (2), (1R*,10R*,11S*,12R*)-dolabella-4(16),7-diene-10,11-epoxy-3,13-dione (3), (1R)-dolabella-4(16),7,11(12)-triene-3,13-dione (4), (1R*,3R*)-3-hydroxydolabella-4(16),7,11(12)-triene-3,13-dione (5), and (1R*,7R*)-7-hydroperoxydolabella-4(16),8(17),11(12)-triene-3,13-dione (6), have been isolated from the Formosan soft coral Clavularia inflata. The structures of compounds 1-6 were determined by 1D and 2D spectral analysis, and their cytotoxicity against selected cancer cells was measured in vitro.     

Cytotoxic cembranoid diterpenes from a soft coral Sinularia gibberosa

Five new alpha-methylene-gamma-lactone-bearing cembranoid diterpenes, sinularolides A-E (1-5), along with 10 known cembranoids, were isolated from the soft coral Sinularia gibberosa. Their structures were determined by extensive spectroscopic (IR, MS, 2D NMR) data analysis. Compounds 2-5 showed moderate activity against selected tumor cell lines.     

Induction of apoptosis by diterpenes from the soft coral Xenia elongata

Four new diterpenes ( 1- 4) were isolated from the soft coral Xenia elongata using a novel cell-based screen for apoptosis-inducing, potential anticancer compounds. The molecular structures of the diterpenes were determined using a combination of NMR and mass spectrometry. The bioactivities were confirmed using a specific apoptosis induction assay based on genetically engineered mammalian lines with differential, defined capacities for apoptosis. The diterpenes induce apoptosis in micromolar concentrations. This is the first report of apoptosis induction by marine diterpenes in xenicane skeletons.     

软珊瑚Sinularia sp.中西松烷二萜类化学成分的分离

方法:运用硅胶柱色谱、Sephadex LH-20柱色谱等分离技术,对中国南海软珊瑚Sinularia sp.的醋酸乙酯部分进行了化学成分的研究.利用1D和2D NMR,EI-MS等分析方法对化合物进行了结构鉴定.结果:从中分离得到6个西松烷二萜类化学成分,分别鉴定为lobophytolide A(1),3-dehydroxylpresinularolide B(2),sarcophine(3),3β-acetoxyisolobophytolide(4),crassocolide D(5),(3E,7E,11E)-6-acetoxy-3,7,11,15(17)-cembratrien-16,14-olide(6).对分离得到的化合物进行了肿瘤细胞抑制活性的初步筛选.结论:化合物1～6均为首次从该生物中获得.     

Dendronpholides A-R, cembranoid diterpenes from the chinese soft coral Dendronephthya sp

A systematic examination of the Chinese soft coral Dendronephthya sp. resulted in the isolation and characterization of 18 new cembranoid diterpenes, namely, dendronpholides A-R (2-19), along with 11-episinulariolide and an enantiomer of sandensolide. Their structures were determined through extensive spectroscopic (IR, MS, 2D NMR) data analyses and by comparison with those reported in literature. The cytotoxicity of several compounds against human tumor cell lines was also evaluated.     

New xenicane diterpenes isolated from the acetone extract of the soft coral Xenia florida

Six new xenicane diterpenes have been isolated from the acetone extract of the soft coral Xenia florida. Two of them are diterpenes containing a bicyclic [4.3.1] ring system. Three of them seem to be precursors for diterpenes possessing the bicyclic [4.3.1] ring system. One is a common monocarbocyclic diterpene with a cyclononane skeleton.     

Sinulodurins A and B, antiproliferative and anti-invasive diterpenes from the soft coral Sinularia dura

Two new diterpenes, sinulodurin A (1) and sinulodurin B (2), along with two known sterols, 24 S-methyl cholesterol and 24-methylene cholesterol, were isolated from the Palau soft coral Sinularia dura. The structures of the new metabolites were determined on the basis of spectroscopic methods and by comparison of NMR data with those of related metabolites. Sinulodurin A (1) and sinulodurin B (2) showed antiproliferative activity against highly malignant +SA mammary epithelial cells with an IC 50 range of 20-30 microM. They also displayed anti-invasive activity against human highly metastatic prostate cancer PC-3M-CT+ cells in the spheroid disaggregation assay. Furthermore, the antimicrobial activities of the isolates were tested.     

Eunicellin diterpenes from two Kenyan soft corals

Six new eunicellin diterpenes designated klyxumines A and B (1, 2) and epoxycladines A-D (3-6) were isolated from Klyxum flaccidum and Cladiella kashmani, collected in Kenya. The structures of the compounds were elucidated by interpretation of MS, COSY, HMQC, HMBC, and NOESY data.     

Tritoniopsins A-D, cladiellane-based diterpenes from the South China Sea nudibranch Tritoniopsis elegans and its prey Cladiella krempfi

Four diterpenes, tritoniopsins A-D (1-4), have been isolated from the South China Sea nudibranch Tritoniopsis elegans and its prey, the soft coral Cladiella krempfi. They display an unprecedented pyran ring in the cladiellane framework, thus representing a novel cladiellane-based diterpene family. Their structures have been mainly characterized by NMR and mass spectrometric techniques, whereas the relative configuration of compound 1 was secured by X-ray analysis. Antiproliferative assays on tumor and nontumor cell lines have been carried out for the main metabolite, tritoniopsin B (2).     

Biscembranes from the soft coral Sarcophyton glaucum

Four novel biscembranes have been isolated from the soft coral Sarcophyton glaucum, collected at Amami Oshima, two of which showed weak activity against proliferation of human promyelocytic leukemia cells (HL-60). Their absolute structures were determined on the basis of the CD spectra.     

Cytotoxic diterpenoids from the soft coral Sinularia microclavata

The soft coral Sinularia microclavata collected from the bay of Sanya, Hainan Island, China, yielded a new diterpenoid, microclavatin (1), and a known cembranolide, capillolide (2). The structure of compound 1 was determined on the basis of spectroscopic methods and X-ray single-crystal diffraction analysis. Microclavatin (1) showed cytotoxic activities against tumor cell lines KB and MCF with IC50 values of 5.0 and 20.0 microg/mL, respectively, and capillolide (2) showed potent cytotoxic activity against tumor cell lines (A-549) with an IC50 value of 0.5 microg/mL.     

Capnellenes from the Formosan soft coral Capnella imbricata

Three anti-inflammatory sesquiterpenes, Delta (9(12))-capnellene-8beta,10alpha-diol ( 1), 8alpha-acetoxy-Delta (9(12))-capnellene-10alpha-ol ( 2), and Delta (9(12))-capnellene-10alpha-ol-8-one ( 3), five new sesquiterpenes, Delta (9(12))-capnellene-8beta,15-diol ( 4), Delta (9(12))-capnellene-8beta,10alpha,13-triol ( 5), Delta (9(10))-capnellene-12-ol-8-one ( 6), 8beta,10alpha-diacetoxy-Delta (9(12))-capnellene ( 7), and 8beta-acetoxy-Delta (9(12))-capnellene ( 8), and a known sesquiterpene, Delta (9(12))-capnellene-8beta-ol ( 9), were isolated from the acetone/methylene chloride extracts of the Formosan soft coral Capnella imbricata. The structures of these compounds were elucidated by extensive spectroscopic analysis.