9,11-Secosterols from the soft corals Sinularia lochmodes and Sinularia leptoclados

Chemical investigations on the EtOAc-soluble fractions from the EtOH extract of two Formosan soft corals afforded two new 9,11-secosteroids, 3beta,11-dihydroxy-5beta,6beta-epoxy-24-methylene-9,11-secocholestan-9-one (1) and 3beta,11-dihydroxy-24-methylene-9,11-secocholestan-9-one (2), from Sinularia lochmodes and Sinularia leptoclados, respectively, along with two known analogues (3 and 4) from S. leptoclados. The structures of the new metabolites were elucidated on the basis of extensive spectroscopic analysis and by comparison of their NMR data with those of the known compound 3. The cytotoxicity of 2-4 toward a limited panel of cancer cell lines is also reported.     

Anti-inflammatory cembranoids from the soft corals Sinularia querciformis and Sinularia granosa

Four new cembranoids, querciformolides A-D (1-4), along with two known cembranoids, 7 and 8, have been isolated from the soft coral Sinularia querciformis. Furthermore, chemical investigation of Sinularia granosa has afforded three new cembranoids, querciformolide B (2) and granosolides A (5) and B (6). The structures of the new metabolites were elucidated on the basis of extensive spectroscopic methods, and that of 2 was further confirmed by X-ray diffraction analysis. The absolute configurations of 1 and 2 were determined by a modified Mosher's method. Among these metabolites, 2-6 are rarely found cembranoids possessing a tetrahydrofuran moiety with a 4,7-ether linkage; in addition, 1 is the first epsilon-lactone cembrane found that possesses a tetrahydropyran moiety with a 4,8-ether linkage. None of these compounds were found to be cytotoxic toward a limited panel of cancer cell lines. However, compounds 3, 7, and 8 significantly inhibited the accumulation of the pro-inflammatory iNOS and COX-2 proteins in LPS-stimulated RAW264.7 macrophage cells.     

A cytotoxic 5alpha,8alpha-epidioxysterol from a soft coral Sinularia species

A new sterol, (22R,23R,24R)-5alpha,8alpha-epidioxy-22, 23-methylene-24-methylcholest-6-en-3beta-ol (1), as well as two known sterols, numersterol A (2) and pregnenolone (3), have been isolated from a soft coral Sinularia sp. The structure of metabolite 1 was determined by spectral analysis. Cytotoxicity of sterols 1-3 toward various cancer cell lines is also reported.     

New beta-caryophyllene-derived terpenoids from the soft coral Sinularia nanolobata

Two new norsesquiterpenoids, nanonorcaryophyllenes A (1) and B (2), two new diterpenoids, nanolobatins A (3) and B (4), and a novel norditerpenoid, nanolobatin C (5), were isolated from the n-hexane extract of the Taiwanese soft coral Sinularia nanolobata. Also, two new furanone derivatives, 6 and 7, were isolated for the first time from natural sources. The structures of 1-5 were elucidated on the basis of extensive spectroscopic analyses and by comparison of the spectral data with those of the related metabolites. Nanonorcaryophyllenes A (1) and B (2) were characterized as 13-norcaryophyllenes that lack a methyl group at C-11, while nanolobatin C (5) represents the first example of a xeniaphyllane-based 17-norditerpenoid. The cytotoxicity of 1-6 against the growth of a limited panel of cancer cell lines is also described.     

Polyoxygenated sterols from the Formosan soft coral Sinularia gibberosa

Chemical investigation on the dichloromethane-soluble fraction from the EtOH extract of Sinularia gibberosa Tixier-Durivault has led to the isolation of three new polyoxygenated sterols, gibberoketosterols B (1) and C (2) and gibberoepoxysterol (3), along with two known steroids, gibberoketosterol (4) and 24-methylenecholest-5-en-3beta-ol (5). These cholestane-type sterols possessing a 22,24(28)-conjugated diene (1 and 2) in the side chain or a 5alpha,6alpha-epoxide in the B-ring (3) were isolated for the first time from marine sources. Compound 4 showed significant inhibition against the up-regulation of the pro-inflammatory iNOS and COX-2 proteins of LPS-stimulated RAW264.7 macrophage cells, while 1 was found to be inactive. The cytotoxicity of 1-4 toward a limited panel of cancer cell lines is also reported.     

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.     

Scabrolides A-D,four new norditerpenoids isolated from the soft coral Sinularia scabra

Four new norditerpenoids, scabrolides A-D (1-4), along with four known ones, 5-8, have been isolated from the dichloromethane extract of the Taiwanese soft coral Sinularia scabra. The structures of 1-4 were elucidated on the basis of extensive spectroscopic analyses, while the relative configurations were determined by the NOESY experiments. The epimeric metabolites 6 and 7 have been shown to exhibit strong cytotoxic activity against KB and Hepa59T/VGH cancer cell lines.     

Manaarenolides A-I, diterpenoids from the soft coral Sinularia manaarensis

Nine cembrane-type diterpenoids, manaarenolides A-I (1-9), along with two known cembranolides, 10 and 11, have been isolated from the ethyl acetate extract of the Taiwanese soft coral Sinularia manaarensis. Among these metabolites, diterpenes (1, 2, 5, and 6) were discovered for the first time as the hydroperoxycembranolides possessing a delta-lactone ring. The 13-epimeric metabolites 7 and 8 have been shown to exhibit moderate cytotoxic activity against Hepa59T/VGH, KB, Hela, and Med cancer cell lines. The biosynthetic relationship between these new metabolites and 10 and 11 is also discussed.     

Oxygenated terpenoids from a formosan soft coral Sinularia gibberosa

Three new oxygenated sesquiterpenoids, gibberodione (1), peroxygibberol (2), and sinugibberodiol (3), along with sarcophytol L (4) were isolated from a Formosan soft coral, Sinularia gibberosa. The structures of the new metabolites were determined on the basis of extensive spectroscopic analyses and by comparison of NMR data with those of related metabolites. Metabolites 2 and 4 were found to exhibit moderate cytotoxicity toward a human liver carcinoma cell line.     

Oxygenated cembranoids from a Formosan soft coral Sinularia gibberosa

Chemical investigation of a Formosan soft coral, Sinularia gibberosa, has led to the isolation of eight oxygenated cembranoids, 1- 8, including seven new compounds, gibberosenes A-G ( 2- 8). None of these compounds were found to be cytotoxic toward a limited panel of cancer cell lines. Compound 1 significantly inhibited the accumulation of the pro-inflammatory COX-2 protein of the LPS-stimulated RAW264.7 macrophage cells.     

Scabrolides E-G, three new norditerpenoids from the soft coral Sinularia scabra

Three new norditerpenoids, scabrolides E-G (1-3), and dissectolide A (4) have been isolated from the organic extract of a Taiwanese soft coral Sinularia scabra. The structures of 1-3 were determined on the basis of extensive spectroscopic analyses and by comparison of their spectral data with those of the known related metabolites. Metabolite 1 was found to exhibit significant cytotoxicity against the growth of Hepa59T/VGH and KB cell lines.     

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.     

A C-3 methylated isocembranoid and 10-oxocembranoids from a formosan soft coral, Sinularia grandilobata

Five new cembranoids, designated grandilobatins A-E (1- 5), were isolated from the soft coral Sinularia grandilobata. Grandilobatin C (3) was found to have a novel skeleton with the C-4 methyl group of the normal cembranoid rearranged to C-3, while the other metabolites were identified as new 10-oxocembranoids. Metabolite 4 has weak cytotoxicity toward MDA-MB-23 human breast tumor cells. Also, 4 significantly inhibited the accumulation of the pro-inflammatory iNOS protein of LPS-stimulated RAW264.7 macrophage cells at 50 microM.     

栎壮短指软珊瑚中细胞毒性9,11-开环甾醇

目的：从栎壮短指软珊瑚中寻找生物活性成分。方法：利用硅胶柱色谱、HPLC等手段分离栎壮短指软珊瑚化学成分,根据化合物的波谱数据鉴定化合物的结构,利用MTT法测定化合物体外细胞毒性。结果：分离得到3个9,11-开环甾醇（1-3）,化合物1-3对SKMG-4,Hep-G2和CNE2三种人体癌细胞具有细胞毒作用。结论：首次从栎壮短指软珊瑚中分离得到3个具有细胞毒性的9,11-开环甾醇。     

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.     

A new cembranolide from the soft coral Sinularia capillosa

A new cembranolide, capillolide (1), and three known cembranolides were isolated from the soft coral Sinularia capillosa collected from the South China Sea. Their structures and the relative stereochemistry of 1 were deduced on the basis of spectroscopic methods.     

A cytotoxic lobane diterpene from the formosan soft coral Sinularia inelegans

A new cytotoxic lobane diterpene, ineleganene (1), was isolated from the Formosan soft coral Sinularia inelegans. The structure of compound 1 was determined by 1D and 2D spectral analysis.     

Sinulaflexiolides A-K, cembrane-type diterpenoids from the chinese soft coral Sinularia flexibilis

A bioassay-guided fractionation and chemical examination of the soft coral Sinularia flexibilis resulted in the isolation and characterization of sinulaflexiolides A-K (1-11), along with sinulariolone (12), 5-dehydrosinularolide (13), capillolide (14), sinulariolide (15), 5,8-epoxy-9-acetoxysinulariolide (16), flexibilide (17), dihydroflexibilide (18), and the enantiomer of 14-deoxycrassin (19). Their structures were determined on the basis of extensive spectroscopic (IR, MS, 2D NMR) data analysis and by comparison with spectroscopic data reported in the literature. Sinulaflexiolides D and E showed selective inhibitory activity against the gastric gland carcinoma cell line BGC-823 at 8.5 and 0.12 microM, respectively.     

中国南海软珊瑚Sinularia flexibilis中西松烷型二萜的研究

 目的对中国南海软珊瑚(Sinularia flexibilis)中的西松烷二萜类成分进行研究,从中寻找有抗肿瘤活性的次生代谢产物。方法采用多种色谱手段进行分离纯化,通过理化性质和光谱分析确定化合物结构。通过抗肿瘤活性筛选方法,研究西松烷二萜的抗肿瘤活性。结果共分离得到4个西松烷二萜类化合物,其结构分别确定为:(1R,13S,12S,9S,8R,5S,4R)-9-Acetoxy-5,8:12,13-diepoxy-cembr-15(17)-en-16,4-olide(1),sinulariolide(2),dihydroflexibilide(3),flexibilide(4)。结论化合物3对所选肿瘤细胞株(BGC-823)显示中等的抑制活性。     

软珊瑚Sinularia inexplicita中两种甾体化合物的分离与鉴定

首次对我国南海软珊瑚Sinularia inexplicita的化学成分进行了研究,从中分离得到2种化合物,经元素分析和波谱分析确定它们的结构分别为24－亚甲基－3β,5α,6β,19－四羟基胆甾烷醇和柳珊瑚甾醇。