Chi-Hsin Hsu

Bioactive norditerpenoids from the soft coral Sinularia gyrosa.

Chemical investigations of the soft coral Sinularia gyrosa resulted in the isolation of six new norcembranolides, gyrosanolides A-F (1-6), a new norcembrane, gyrosanin A (7), and 11 known norditerpenoids 8-18. The structures of the isolated compounds were elucidated through extensive spectroscopic data and by comparison with reported data in the literature. Compounds 1-3, 7-9, 12, and 13 at concentration of 10microM did not inhibit the COX-2 protein expression, but significantly reduced the levels of the iNOS protein (55.2+/-14.6%, 18.6+/-6.7%, 10.6+/-4.6%, 66.9+/-5.2%, 10.2+/-5.1%, 17.4+/-7.2%, 47.2+/-11.9%, and 56.3+/-5.1%, respectively) by LPS stimulation. Compound 8 showed significant antiviral activity against HCMV (human cytomegalovirus) cells with an IC(50) of 1.9microg/mL.

Simplexins A-I, eunicellin-based diterpenoids from the soft coral Klyxum simplex.

Nine new eunicellin-based diterpenoids, simplexins A-I (1-9), were isolated from a Dongsha Atoll soft coral, Klyxum simplex. The structures of these compounds were established by detailed spectroscopic analysis (IR, MS, 1D and 2D NMR) and by comparison with the physical and spectral data of related known compounds. The absolute configuration of 1 was determined by a modified Moshers method. Compounds 1, 4, and 5 were found to be cytotoxic toward a limited panel of cancer cell lines. Compound 5 was shown to significantly inhibit the accumulation of the pro-inflammatory iNOS and COX-2 proteins in LPS-stimulated RAW264.7 macrophage cells.

Cembranoids from the octocoral Sarcophyton ehrenbergi.

Chemical investigation of the octocoral Sarcophyton ehrenbergi led to the isolation of six new cembranoids, (+)-12-carboxy-11Z-sarcophytoxide (1), (+)-12-methoxycarbonyl-11Z-sarcophine (3), ehrenberoxides A-C (4-6), and lobophynin C (2), along with two known compounds, (+)-sarcophytoxide (7) and (+)-sarcophine (8). The structures of these isolated metabolites were elucidated through extensive spectroscopic analyses, while the relative configuration of 1 was confirmed by X-ray diffraction analyses. The chemical evidence combined with spectroscopic and physical data suggested that the locations of the epoxide and the methyl carboxylate for lobophynin C should be exchanged. Moreover, metabolites 1-6 were evaluated in vitro for their cytotoxicity against selected cancer and normal cells lines, antiviral activity against human cytomegalovirus, and antibacterial activity against Salmonella enteritidis.

Anti-inflammatory cembranolides from the soft coral Lobophytum durum.

Chemical investigation of the soft coral Lobophytum durum resulted in the isolation of seven new cembranolides, durumolides F-L (1-7), as well as one previously characterized cembranolides, sinularolide D (8). The molecular structures of these isolated metabolites were determined mainly through NMR techniques and HRESIMS analysis. Moreover, the absolute configurations of 1 and 5 were established by application of modified Moshers method. The antibacterial activities, anti-inflammatory effects, and anti-HCMV (Human cytomegalovirus) endonuclease activity of metabolites 1-8 were also evaluated in vitro. Anti-inflammatory activity of metabolites 1 and 6 (10 microM) significantly reduced the levels of the iNOS protein to 0.8+/-0.6% and 5.7+/-2.2%, respectively, and COX-2 protein to 47.8+/-9.0% and 71.6+/-5.8%, respectively. Metabolites 1-8 (100 microg/disk) exhibited weak antibacterial activity against Salmonella enteritidis.

Antiviral and anti-inflammatory diterpenoids from the soft coral Sinularia gyrosa.

Chemical investigation of the soft coral Sinularia gyrosa led to the purification of three new diterpenoids, designated as gyrosanols A-C (1-3). The structures of 1-3 were elucidated through extensive spectroscopic analyses. Compounds 1 and 2 exhibited antiviral activity against HCMV with IC(50)s of 2.6 and 3.7 microM, respectively. In addition, compounds 1 and 2 showed significant anti-inflammatory activity by reducing the levels of the COX-2 protein (19.6 + or - 3.9% and 29.1 + or - 9.6%, respectively) in RAW 264.7 macrophages.

New 19-oxygenated and 4-methylated steroids from the Formosan soft coral Nephthea chabroli.

Chemical investigation of the Formosan soft coral Nephthea chabroli resulted in the isolation of four new 19-oxygenated steroids, nebrosteroids I-L (1-4), together with a new 4alpha-methylated steroid, nebrosteroid M (5). The molecular structures of these isolated metabolites were elucidated on the basis of extensive spectroscopic analysis and by comparison of the data with those of related metabolites. Compounds 1-5 were evaluated for anti-inflammatory activity using RAW 264.7 macrophages.

New anti-inflammatory 4-methylated steroids from the Formosan soft coral Nephthea chabroli

Eight new 4-methylated steroids, nebrosteroids A-H (1-8) were isolated from the acetone solubles of the Formosan soft coral Nephthea chabroli. The structures were elucidated by extensive NMR spectroscopic analysis and their anti-inflammatory activity was measured in vitro.

Crassocolides N–P, three cembranoids from the Formosan soft coral Sarcophyton crassocaule

Seven new polyoxygenated cembranoids possessing an α‐methylene‐γ‐lactone group, crassocolides G–M (1–7, resp.), have been isolated from the AcOEt extract of the Formosan soft coral Sarcophyton crassocaule. The structures of compounds 1–7 were established by detailed spectroscopic analyses, including 2D‐NMR spectroscopy (1H,1H‐COSY, HMQC, HMBC, and NOESY), while the absolute configuration of 1 was determined using a modified reaction of Moshers method. The cytotoxicity of compounds 1–7 against a limited panel of cancer cell lines was also determined.

New terpenoids from the soft corals Sinularia capillosa and Nephthea chabroli.

Two new terpenoids, capillosanol (1) and chabranol (2), possessing unprecedented terpenoid skeletons, were isolated from the soft corals Sinularia capillosa and Nephthea chabroli, respectively. The structures of 1 and 2 were elucidated through extensive spectroscopic analyses. The cytotoxicities of these compounds were tested in vitro.

Anticancer Drugs Discovery and Development from Marine Organisms

The chemical and biological diversity of the different marine evolutionary group is endless and therefore, this is an amazing resource for the discovery of new anticancer drugs. Comprising 34 of the 36 Phyla of life, marine ecosystems are indeed our last genetic diversity and biotechnological boundary; terrestrial systems possess only 17 Phyla. Sponges, coelenterates and microorganisms are the foremost resources of therapeutic compounds. Algae, echinoderms, tunicates, mollusks, bryozoans are also the sources of anticancer drugs from marine resources. We highlight the past and current status of marine anticancer pharmacology using different marine groups.