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

Abstract

Four new sesquiterpene hydroquinones, xishaeleganins A–D (6–9), along with eleven known related ones (12 and 14–23) were isolated from the Xisha marine sponge Dactylospongia elegans (family Thorectida). Their structures were determined by extensive spectroscopic analysis, ECD calculations, and by comparison with the spectral data reported in the literature. Compounds 7, 15, 20, and 21 showed significant antibacterial activity against Staphylococcus aureus, with minimum inhibitory concentration values of 1.5, 2.9, 5.6, and 5.6 µg/mL, which are comparable with those obtained for the positive control vancomycin (MIC: 1.0 µg/mL).

Dactylospongia elegans—A Promising Drug Source: Metabolites, Bioactivities, Biosynthesis, Synthesis, and Structural-Activity Relationship

“…In addition, compounds 7, 49, 51, 54, and 57 displayed significant potential versus E. faecium (MICs 1.4-5.6 µg/mL). These results suggested that the sesquiterpene quinones/hydroquinones as 57 and 49 possessed the possibility to be the new lead metabolites of antibiotics [27].…”

“…Sesquiterpenes 2.1.1. Sesquiterpenic Quinones/Hydroquinones Sesquiterpenic quinones/hydroquinones are a class of natural marine metabolites that are mainly reported from order Dictyoceratida sponges, including various genera such as Dysidea, Fenestraspongia, Hyrtios, Dactylospongia, Petrosaspongia, Spongia, and Hippospongia [27,32]. They can be either with the drimane or rearranged drimane (clerodane-decalin or 4,9-friedodrimane) skeleton, having four stereo-genic centers.…”

“…AntibacterialBroth microdilution/S. aureus USA300 LAC 5.6 µg/mL (MIC) Vancomycin 1.0 µg/mL (MIC)[27] Broth microdilution/S. pyogenes ATCC 12344 2.8 µg/mL (MIC) Vancomycin 0.25 µg/mL (MIC)[27] Broth microdilution/E.…”

Cytotoxic and Antibacterial Isomalabaricane Terpenoids from the Sponge Rhabdastrella globostellata

“…The MIC values for all antimicrobial agents were measured by 96-well microdilution method . MIC values of these compounds were defined as the lowest concentration to inhibit the bacterial growth completely.…”

Marine natural products

“…Merosesquiterpenoids were isolated from sponges of genus Dactylospongia 1048-1051, Dysidea 1052-1055, and Spongia 1056-1058, respectively. 400,401 Note 1057, named pelorol A, is a methylated congener of known pelorol, and so logically should be termed pelorol B. 402 Meroditerpenoid alkaloids 1059-1062 were discovered from a Mexican Agelas citrina sponge, with some showing antimicrobial properties.…”