Isolation and Identification of Cyclooctasulfur From the Octocoral Sinularia humilis (van Ofwegen, 2008)

Abstract

Chemical examination of the octocoral Sinularia humilis, collected in the waters of Taiwan, led to the isolation of S8 (1). Its structure was determined by a single-crystal x-ray diffraction analysis and this is the first time that S8 has been reported from a marine invertebrate.

Marine natural products

“…S 8 was isolated from a Taiwanese collection of Sinularia humilis and the structure confirmed by XRD. 526 A number of simple lipids and quinonoid MNPs were reported from cnidarians including dendronephthyones A–C 1171–1173 isolated from a Vietnamese collection of Dendronephthya mucronata , 527 a simple epoxy-derivative of flexibilisquinone 1174 from southern Taiwan specimens of Sinularia scabra , 528 the related hydroquinone sarcotenuhydroquinone 1175 from Sarcophyton tenuispiculatum (cultured specimens), 529 and a series of terpenoid amide derivatives of spermidine and spermine sinularamide A–G 1176 , 1177 , 1178 and 1179–1182 isolated from Sinularia sp. 530 Sinularamide C exhibited weak inhibition of casitas B-lineage lymphoma proto-oncogene B with a potential role of enhancing the adaptive and innate immune system with implications for antitumour immunotherapies.…”

Octasulfur in Alcyonarians and Ascidians

“…This information will be a good addition to the interesting finding of S8 in an alcyonarian. 1 Vladimir I. Kalinin…”

“…The finding of a biologically active metabolite having no NMR signals in the alcyonarian Sinularia humilis (family Alcyoniidae, suborder Alcyoniina, order Alcyonacea, subclass Octocorallia, class Anthozoa, phylum Cnidaria), namely octasulfur S 8 , which was characterized by X-ray analysis, seems to be very uncommon and interesting. 1 The authors noted: “To the best of our knowledge, this is the first occasion on which cyclooctasulfur was obtained from a marine invertebrate.” However, investigations by the scientists of G. B. Elyakov Pacific Institute of Bioorganic Chemistry of the Russian Academy of Sciences, and published in 1995, 2 reported the isolation of this compound from an ascidian. This work used a slightly different methodology, but with the same result.…”