Bioactive Isoprenoid-Derived Natural Products from a Dongsha Atoll Soft Coral Sinularia erecta

Abstract

Four new isoprenoids, including two norcembranoids sinulerectols A and B (1 and 2), a cembranoid sinulerectol C (3), and a degraded cembranoid sinulerectadione (4), along with three known isoprenoids, an unnamed norcembrene (5), sinularectin (6), and ineleganolide (7), and a known nitrogen-containing compound (Z)-N-[2-(4-hydroxyphenyl)ethyl]-3-methyldodec-2-enamide (8), were isolated from an extract of the marine soft coral Sinularia erecta. The structure of sinularectin (6) was revised, too. Compounds 3, 4, and 8 exhibited inhibitory activity against the proliferation of a limited panel of cancer cell lines, whereas 1, 2, and 8 displayed potent anti-inflammatory activity in fMLP/CB-stimulated human neutrophils.

Bioactive Steroids from the Formosan Soft Coral Umbellulifera petasites

“…As in previously described procedures, the assay of superoxide anion generation was conducted according to the SOD-inhibitable reduction of ferricytochrome C. The elastase release experiment was performed using MeO–Suc–Ala–Ala–Pro–Val– p -nitroanilide as the enzyme substrate [23]. Idelalisib, a selective inhibitor of phosphatidylinositol-3-kinase, was used as a positive control for inhibition of superoxide anion generation and elastase release with IC 50 0.07 ± 0.01 and 0.3 ± 0.1 μM [24]. …”

Hydroperoxyditerpenoids from Octocorals

“…In 2016, Huang et al ., reported a 11‐hydroperoxy‐cembranoid, sinulerectol C ( 49 ) (Figure ), obtained from S. erecta , collected off the coast of Dohgsha Atoll, Taiwan . The structure of cembranoid 49 was elucidated by spectroscopic methods, and this compound was found to exhibit cytotoxicity towards the K‐562 tumor cells, with an IC 50 value of 9.2 μM …”

New Cembranoids and a Biscembranoid Peroxide from the Soft Coral Sarcophyton cherbonnieri

“…Many cembrane-based natural products have been shown to exhibit significant activities such as cytotoxicity [1,2,3,4,5,6,7,8,9,10,11,12,13,14] and anti-inflammatory activity [9,11,13,14,15,16,17,18]. From the experience of searching bioactive metabolites from soft corals, series of cembranoids have been unveiled from octocorals (Alcyonaceae) belonging to the genera Sarcophyton , [1,2,3,4,5,6,7,8,16], Sinularia [9,10,11,12,17,18] and Lobophyton [13,14,15].…”

“…From the experience of searching bioactive metabolites from soft corals, series of cembranoids have been unveiled from octocorals (Alcyonaceae) belonging to the genera Sarcophyton , [1,2,3,4,5,6,7,8,16], Sinularia [9,10,11,12,17,18] and Lobophyton [13,14,15]. Also, previous studies showed that two cembranoid units could form biscembranoid-type compounds by Diels-Alder reaction [19,20,21], radical dimerization [22,23], or connection with a sulfur atom [18], making the chemistry of cembranes more complex and interesting than monomeric form.…”