Renierosides, Cerebrosides from a Marine Sponge Haliclona (Reniera) sp.

Abstract

Guided by the brine shrimp lethality assay, eight new cerebrosides (1-8) have been isolated from an extract of the marine sponge Haliclona (Reniera) sp. A novel feature of these cerebrosides was the presence of unprecedented amide-linked long-chain fatty acid moieties. The planar structures of the cerebrosides (1-8) were established by 1D and 2D NMR spectroscopic techniques, mass spectrometric analyses, and chemical degradation methods. The isolated compounds did not display cytotoxicity to a panel of five human solid tumor cell lines.

New Cerebrosides from a Marine Sponge Haliclona (Reniera) sp.

“…by Prof. Sim, C. J. and has been described elsewhere. 5) A voucher specimen of the sponge (registry No. Spo.…”

“…In our previous study on the marine sponge Haliclona (Reniera) sp., we reported the isolation and structure elucidation of eight new cerebrosides 5) and a new sphingosine 6) obtained from the MeOH extract. Cerebrosides and sphingosine derivatives have been isolated from diverse natural sources, including plants, 7) marine sources, 8) microorganisms, 9) and human.…”

“…10) Phytosphingosine type cerebrosides are reported to exhibit bioactivities such as the antitumor, 11) antiviral, 12) inhibition of histidine decarboxylase, 13) cytotoxicity, 14) and antifungal activity. 14) In a continuing study on the same sponge, fourteen phytosphingosine type cerebrosides (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14) were isolated from the n-hexane layer. Nine (1-9) of them contained saturated acyl chains, while five (10)(11)(12)(13)(14) possessed unsaturated acyl chains.…”

“…Separation of the n-hexane layer by medium pressure liquid chromatography (MPLC) on a normal-phase flash column yielded 20 fractions. Fraction 16 was found to contain sugar moieties as observed in 1 H-NMR spectra, and was subjected to repeated HPLC chromatographic separation using ODS column to yield nine cerebrosides (1)(2)(3)(4)(5)(6)(7)(8)(9). And the mixture of fractions 10 to 15 afforded five analogues (10)(11)(12)(13)(14) through HPLC separation using the same condition as for fraction 16.…”

Síntese de novas amidas graxas a partir da aminólise de ésteres metílicos

“…e também em mamíferos como, por exemplo, em barbatanas de baleias, no fluído cérebro-espinhal de ratos e gatos, no plasma sanguíneo, no tecido adiposo, no cérebro, intestino e outros tecidos de ratos e porcos. [12][13][14][15][16][17][18][19][20][21][22][23] A ocorrência de amidas graxas também foi verificada em organismos unicelulares como, por exemplo, a Corynebacterium nitrilophilus, algumas espécies de Streptomyces e células de câncer de mama. Na cianobactéria marinha Lyngbya majuscula foram identificadas as amidas graxas, hermitamidas, grenadamida, semiplenamidas C e as besar-hanamidas A e B.…”