Two New Ceramides from the Marine Sponge Ircinia fasciculata

Abstract

A new 4-sulfated ceramide, ircisulfamide ( N-[(1S*,2S*,3R*)-2-hydroxy-1-(hydroxymethyl)-3-(sulfooxy)-heptadecyl]hexadecanamide; 1), and a new glycosphingolipid, ircicerebroside ( (2R*)-N-{(1S*,2R*,3E,7E)-1-[(b-d-glucopyranosyloxy)methyl]-2-hydroxy-8-methylheptadeca-3,7-dienyl}-2-hydroxyeicosanamide; 2), were isolated from the aqueous EtOH extract of the marine sponge Ircinia fasciculata (Pallas). The structures of the new compounds were elucidated on the basis of spectroscopic analysis and by means of chemical methods.Introduction. ± Different sphingolipids such as ceramide, sphingosine, and sphingosine-1-phosphate have been isolated from marine vertebrates, invertebrates, algae, and fungi etc. [1 ± 3]. These compounds have received increasing attention in the last years as some of their derivatives act as endogenous cell-function modulators and secondary messengers [4]. Sphingolipids have been shown to be potent and specific inhibitors of protein kinase C [5], Na-and K-ATPase, and calmodulin kinase, and to activate phospholipase C, phospholipase D, casein kinase II, tyrosine kinase, and DG kinase [6]. In addition, sphingolipids can also induce Ca 2 release [7], proliferate cells [8], protect human keratinocytes from apoptosis [9], suppress colon carcinogenesis in rats [10], and enhance apoptosis of radiation-resistant prostate cancer cells [11].In continuation of our search for potent bioactive secondary metabolites from the marine invertebrates [12 ± 14], a new 4-sulfated ceramide, ircisulfamide (1), and a new glycosphingolipid, ircicerebroside (2), were isolated from the aqueous EtOH extract of the marine sponge Ircinia fasciculata. The structures of compounds 1 and 2 were elucidated on the basis of spectroscopic analysis and chemical methods.

Aureobasidin, New Antifouling Metabolite from Marine-Derived Fungus Aureobasidium sp

“…One gave a fragmentation pattern identical to that of methyl-3,5dihydroxydecanoate (compound 2 methyl ester derivative), while the other component (218 [M] + ) showed a fragment at m/z 161 (69%) due to cleavage of the bond between C-6 and C-7 [18], and another fragment at m/z 57 (12%) due to C 4 H 9 , which According to previous findings, compound 1 was identified as [21,22]. Comparing the chemical shifts and splitting pattern of H-3 and H-5 with those of similar dihydroxy fatty acid residues identified the relative configuration at C-3 and C-5 to be 3S and 5R [18][19][20]. According to these results, compound 2 was identified as (3R,5S)-3,5dihydroxydecanoic acid.…”

Monitoring Bacterial Diversity of the Marine Sponge Ircinia strobilina upon Transfer into Aquaculture

“…(5). Other compounds of potential biomedical importance from the genus Ircinia include two murine and human cancer cell growth inhibitors, irciniastatin A and B (47), and a ceramide (77).…”

Glycolipids from Marine Invertebrates

“…This contained 2-hydroxy FAs and its base was the same as above, 2-amino-9-methyloctadeca-4E,8E-diene-1,3-diol. The same sphingosine type was identified again in the ceramide part of an isolated pure GSL, ircicerebroside, from the sponge Ircinia fasciculata collected from Wei-zhou Island, China (Zhang et al, 2005). Ircicerebroside was present in the GSL mixture of M. senile.…”

“…The octocoral Sarcophyton eherenbergi, collected in Taiwan waters, and already cited for containing a new a-glucocerebroside with a triunsaturated long-chain base, also contained a new b-glucocerebroside. Its ceramide part possess the same diunsaturated base type as M. senile and I. fasciculata (Karlsson, Leffler, and Samuelsson, 1979;Zhang et al, 2005) (Table 5.3). Among several metabolites isolated from the soft coral Lobophytum sp., collected in the Indian Ocean, a pure unprecedented glucocerebroside was identified bearing the same diunsaturated sphingoid base as in the latter reports, and a saturated 2-hydroxy FA (Muralidhar et al, 2005).…”