Four Cytotoxic Spongian Diterpenes from the Sponge <i>Dysidea</i> cf. <i>arenaria</i>

Abstract

Chemical analysis of the sponge Dysidea cf. arenaria from Irabu Island provided four new diterpenes 1-4. Their structures were elucidated by NMR and other spectroscopic analyses. All the metabolites retained the spongian skeleton and an isovalerate ester, but were different from those previously isolated from a specimen of Okinawa Island, implying geographic variation. The cytotoxicity of compounds 1-4 to NBT-T2 cells was evaluated and their IC 50 values were 3.1, 1.9, 8.4, and 3.1 µM, respectively. Key words spongian diterpene; Dysidea; cytotoxicity; sponge Ever since the earliest days of marine natural products chemistry, sponges have attracted the attention of many researchers for their bountiful reserve of novel molecules and biological activities, which have been used as principal targets for bioactive molecules among sessile marine organisms.1) Of the sponge genera, the genus Dysidea is a prolific source of secondary metabolites.2) A number of new molecules have been isolated from Dysidea sponges in the last few years. Examples include dysidaminones, which show nuclear factorkappa B (NF-κB) inhibitory activity 3)

Marine natural products

“…Geodiataurine exhibited weak activity (IC 50 ¼ 8.5 mM) against A2058 melanoma cells but with no antibacterial effects. 454 Other diterpenoids, 949 and 950 (total syntheses also achieved), 455 especially based upon the ubiquitous spongian diterpene skeleton 951-962, [456][457][458] were isolated from Theonella, Dysidea, Spongia and Dendrilla sponges, all with varying activities. Several norscalarane 963-967 (ref.…”

Spongian Diterpenes Including One with a Rearranged Skeleton from the Marine Sponge Spongia officinalis

“…To date, about 200 spongian diterpenes and rearranged derivatives have been reported since the first spongian diterpene, named isoagatholactone, was isolated from the sponge Spongia officinalis (family Spongiidae) collected in the Mediterranean . Some of these compounds were reported to possess a variety of pharmaceutical bioactivities, such as cytotoxic, anti-inflammatory, and antiviral properties. − Spongia species of the South China Sea have been rarely chemically investigated, with only three studies reporting three new spongian diterpenes and two novel trinorsesquiterpenoids from the title species and nine sesquiterpene quinones/hydroquinones from S. pertusa , making them an understudied resource of chemical diversity for potential drug discovery efforts. In the course of our continuing research on bioactive molecules from marine invertebrates of the South China Sea, − a specimen of the previously investigated sponge, S. officinalis , was re-collected.…”

Aaptamine-rich Fraction from the Indonesian Marine Sponge, Aaptos suberitoides, Exhibits a Cytotoxic Effect on DLD-1 Colorectal Cancer Cells

“…The marine sponge extraction method refers to [25]. The specimen (146.30 g, wet) was thawed, chopped, and macerated using methanol (MeOH) until submerged overnight before being filtered.…”