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.

The chemistry of Briareum excavatum, a Formosan gorgonian coral, was investigated. This study has led to the isolation of five novel marine natural products, excavatolides A-E (1-5), together with brianolide (6). The structures of the above compounds were established by spectral and chemical methods. The relative configuration of excavatolide B (2) was further confirmed by a single-crystal X-ray structure analysis. Cytotoxicity of these compounds toward various cancer cell lines also is described.

Three decades ago, the marine-derived compound sinularin was shown to have anti-edematous effects on paw edema induced by carrageenan or adjuvant. To the best of our knowledge, no new studies were conducted to explore the bioactivity of sinularin until we reported the analgesic properties of sinularin based on in vivo experiments. In the present study, we found that sinularin significantly inhibits the upregulation of proinflammatory proteins, inducible nitric oxide synthase (iNOS), and cyclooxygenase-2 (COX-2) and upregulates the production of transforming growth factor-β (TGF-β) in lipopolysaccharide (LPS)-stimulated murine macrophage RAW 264.7 cells according to western blot analysis. We found that subcutaneous (s.c.) administration of sinularin (80 mg/kg) 1 h before carrageenan injection significantly inhibited carrageenan-induced nociceptive behaviors, including thermal hyperalgesia, mechanical allodynia, cold allodynia, and hindpaw weight-bearing deficits. Further, s.c. sinularin (80 mg/kg) significantly inhibited carrageenan-induced microglial and astrocyte activation as well as upregulation of iNOS in the dorsal horn of the lumbar spinal cord. Moreover, s.c. sinularin (80 mg/kg) inhibited carrageenan-induced tissue inflammatory responses, redness and edema of the paw, and leukocyte infiltration. The results of immunohistochemical studies indicate that s.c. sinularin (80 mg/kg) could upregulate production of TGF-β1 in carrageenan-induced inflamed paw tissue. The present results demonstrate that systemic sinularin exerts analgesic effects at the behavioral and spinal levels, which are associated with both inhibition of leukocyte infiltration and upregulation of TGF-β1.

This review reports details on the natural products isolated from Taiwan soft corals during the period 2008–2012 focusing on their in vitro and/or in vivo anti-inflammatory activities. Chemical structures, names, and literature references are also reported. This review provides useful and specific information on potent anti-inflammatory marine metabolites for future development of immune-modulatory therapeutics.

Five new cembranoids, namely, crassumolides A and B and D-F (1 and 2 and 4-6), along with four known metabolites, 7-10, were isolated from the soft coral Lobophytum crassum. Crassumolide C (3) was isolated for the first time from a natural source. The structures of these compounds were elucidated by extensive spectroscopic analysis and comparison of the NMR data with those of known analogues. The absolute stereochemistry of 1 was determined using the modified Mosher's method. Chemical transformation of 7 into the corresponding methyl ester 3 revealed the absolute stereochemistry of 3. Compounds 1, 3, and 7 were cytotoxic toward Ca9-22 cancer cells, and 10 was broadly cytotoxic toward all six test cancer cell lines used. Compounds 1, 3, 7, and 10 were found to inhibit the accumulation of the pro-inflammatory proteins iNOS and COX-2 at 10 μM.

Six new withanolides, paraminabeolides A-F (1-6), along with five known compounds, minabeolides-1, -2, -4, -5, and -8 (7-11), were isolated from a Formosan soft coral, Paraminabea acronocephala. The structures of these compounds were elucidated by extensive spectroscopic analysis and chemical transformation. The absolute configuration of 4 was determined by the application of Mosher's method. Compounds 1 and 7 were cytotoxic toward Hep G2 cancer cells. Compounds 1-4 and 7-10 were found to significantly inhibit the accumulation of the pro-inflammatory iNOS protein. Compounds 7-10 also could effectively reduce the expression of COX-2 protein.

Three new briaran diterpenes, 2β-acetoxy-2-(debutyryloxy)stecholide E (3), 9-deacetylstylatulide lactone (4), and 4β-acetoxy-9-deacetylstylatulide lactone (5), and two known diterpenes, brianthein W (1) and 9-deacetylbriareolide H (2), have been isolated from a Briareum sp. of gorgonian. The structures and relative stereochemistry of these compounds were determined by spectroscopic and chemical methods. Diterpenes 2−4 and the corresponding 9-acetyl derivatives 6, 7, and 12 exhibited cytotoxicity toward various cancer cell lines.

Fucosterol (1), 24xi-hydroperoxy-24-vinylcholesterol (2), 29-hydroperoxystigmasta-5,24(28)-dien-3beta-ol (3), 24-ethylcholesta-4,24(28)-dien-3-one (4), 24xi-hydroperoxy-24-ethylcholesta-4,28(29)-dien-3-one (5), 24-ethylcholesta-4,24(28)-dien-3,6-dione (6), 24xi-hydroperoxy-24-ethylcholesta-4,28(29)-dien-3,6-di one (7), 6beta-hydroxy-24-ethylcholesta-4,24(28)-dien-3-one (8), and 24xi-hydroperoxy-6beta-hydroxy-24-ethylcholesta-4,28(2 9)-dien-3-one (9) were isolated from the marine brown alga Turbinaria conoides. The structures of these compounds were established by spectral analysis. Isolated for the first time from a natural source, the oxygenated fucosterols 4-9 exhibit cytotoxicity against various cancer cell lines.