Popolohuanones G – I, Dimeric Sesquiterpene Quinones with IL‐6 Inhibitory Activity from the Marine Sponge Dactylospongia elegans

Abstract

Chemical investigation of the marine sponge Dactylospongia elegans, collected from the South China Sea, afforded three new dimeric sesquiterpene quinones, popolohuanones G - I (1 - 3), together with two known analogs, popolohuanones B (4) and C (5). The new structures were determined by HR-ESI-MS and 1D- and 2D-NMR analyses. All the five compounds showed no cytotoxic activity against five human cancer cell lines, while popolohuanone H (2) showed potent inhibitory activity against IL-6, an inflammatory cytokine, at the concentration of 10 μm.

Calamene-Type Sesqui-, Mero-, and Bis-sesquiterpenoids from Cultures of Heimiomyces sp., a Basidiomycete Collected in Africa

“…Nevertheless, two sesquiterpenoids being linked via a p -benzoquinone is an uncommon feature for natural products . So far only a few similar compounds, like popolohuanones F–H , and nakijiquinone E, have been described in the literature.…”

Xishaeleganins A–D, Sesquiterpenoid Hydroquinones from Xisha Marine Sponge Dactylospongia elegans

“…Among them, the known compounds were readily identified as dactyloquinone C (12) [25], polyfibrospongol A (14) [26], dictyoceratin A (15) [27], dictyoceratin B (16) [27], dictyoceratin C (17) [28], dactyloquinone A (18) [29], dactyloquinone B (19) [29], ilimaquinone (20) [30], epi-ilimaquinone (21) [31], dactyloquinone D (22) [25], and dactyloquinone As part of our ongoing project towards the isolation of biologically active compounds from Chinese marine benthic invertebrates [18][19][20], a batch of Dactylospongia elegans sponges was collected off the coast of Xisha Island, Hainan Province, China, and chemically investigated. Dactylospongia elegans sponges belonging to the family Thorectida (order Dictyoceratida, class Demospongiae, and phylum Porifera) are prolific sources of biologically active compounds spanning a wide range of structural classes, from meroterpenoids [21,22], steroids [23], to diterpenoids [24], etc. In this report, we describe the isolation of four new sesquiterpene hydroquinones, xishaeleganins A-D (6-9), along with eleven known related ones (12 and 14-23) from the titular animals.…”

“…Among them, the known compounds were readily identified as dactyloquinone C (12) [25], polyfibrospongol A (14) [26], dictyoceratin A (15) [27], dictyoceratin B (16) [27], dic-tyoceratin C (17) [28], dactyloquinone A (18) [29], dactyloquinone B (19) [29], ilimaquinone (20) [30], epi-ilimaquinone (21) [31], dactyloquinone D (22) [25], and dactyloquinone E (23) [25], by comparing their NMR data and optical rotation values with those reported in the literature.…”

“…In conclusion, although the chemical studies on the South China Sea sponges D. elegans have been well documented in literature [5,[21][22][23], the chemical reinvestigation of the same species collected from the same water area has still provided additional interesting and innovative results. The notable contribution towards the advance of meroterpenoid chemistry is the discovery of four new chemically diverse sesquiterpene hydroquinones, namely xishaeleganins A-D (6)(7)(8)(9).…”

“…sponges was collected off the coast of Xisha Island, Hainan Province, China, and chemically investigated. Dactylospongia elegans sponges belonging to the family Thorectida (order Dictyoceratida, class Demospongiae, and phylum Porifera) are prolific sources of biologically active compounds spanning a wide range of structural classes, from meroterpenoids [21,22], steroids [23], to diterpenoids [24], etc. In this report, we describe the isolation of four new sesquiterpene hydroquinones, xishaeleganins A-D (6)(7)(8)(9), along with eleven known related ones (12 and 14-23) from the titular animals.…”