Toporosides A and B, Cyclopentenyl-Containing ω-Glycosylated Fatty Acid Amides, and Toporosides C and D from the Northwestern Pacific Marine Sponge Stelodoryx toporoki

Abstract

Toporosides A−D (1−4), new ω-glycosylated fatty acid amides, were isolated from the sponge Stelodoryx toporoki. The structures of these compounds, including absolute configurations of stereogenic centers, were established using analysis of 1D and 2D NMR, ECD, and HR mass spectra as well as chemical transformations. Toporosides A (1) and B (2) are the first lipids containing a cyclopentenyl α,β-unsaturated carbonyl moiety in the polymethylene chain. Toporoside C (3) is likely a precursor, which undergoes intramolecular aldol condensation to produce 1 and 2. Toporosides A, C, and D showed protective effects against TNF-α-induced injury in H9c2 cardiomyocytes.

Marine natural products

“…Three of the isolates prevent TNF-a-induced damage to rat cardiac cells at non-toxic concentrations; based upon SAR analysis, the C-11 carbonyl is important for cardio-protective activity. 368 A series of alkynynols 918-934 and polyacetylenes 935-937 have been reported from Cribrochalina and Petrosia sponges, respectively, 369,370 while plakilactone J 938 is an ethyl-branched polyketide g-lactone and its absolute conguration was determined using VCD data. 371 As always, many peptidic MNPs were reported from sponges in 2022.…”

Assimiloside A, a Glycolipid with Immunomodulatory Activity from the Northwestern Pacific Marine Sponge Hymeniacidon assimilis

“…Hydroxy fatty acids were mainly found as structural units of resin glycosides, a group of natural products comprising oligosaccharides and organic acids, mostly obtained from the higher plants of the Convolvulaceae family and having broad biological properties, such as purgative, antibacterial, antimalaria, antidepressant, and anticonvulsant activities. 4−6 As part of our ongoing program to search for bioactive compounds from Northwestern Pacific marine invertebrates, 7 we have isolated a new glycolipid, assimiloside A, structurally resembling resin glycosides. However, it has a number of structural features previously not found in other glycolipids including an unprecedented γ-lactone of 4R,16,26R-trihydroxy C 28 fatty acid as aglycon and a branched trisaccharide moiety consisting of two D-xylose and D-glucose units.…”

“…As part of our ongoing program to search for bioactive compounds from Northwestern Pacific marine invertebrates, we have isolated a new glycolipid, assimiloside A, structurally resembling resin glycosides. However, it has a number of structural features previously not found in other glycolipids including an unprecedented γ-lactone of 4 R ,16,26 R -trihydroxy C 28 fatty acid as aglycon and a branched trisaccharide moiety consisting of two d -xylose and d -glucose units.…”