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Halisphingosines A and B, modified sphingoid bases from Haliclona tubifera. Assignment of configuration by circular dichroism and van't Hoff's principle of optical superposition.

ABSTRACT: Halisphingosines A (1) and B (2), modified long-chain sphingoid bases, from the marine sponge Haliclona tubifera collected in Brazil, were characterized after conversion to their N-Boc derivatives. The 2R,3R,6R configuration of halisphingosine A, a compound first reported from Haliclona sp. from South Korea, was confirmed using a novel CD approach: deconvolution of exciton coupling from mono- and trinaphthoyl derivatives obtained by derivatization of the natural product. The sensitive CD deconvolution method, applicable to submilligram samples, simultaneously predicted the relative and absolute configuration of three stereocenters in halisphingosine A with precision and accuracy. Halisphingosine B was assigned by correlation to halisphingosine A.

SUBMITTER: Molinski TF

PROVIDER: S-EPMC3969749 | biostudies-literature | 2013 Mar

REPOSITORIES: biostudies-literature

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Halisphingosines A and B, modified sphingoid bases from Haliclona tubifera. Assignment of configuration by circular dichroism and van't Hoff's principle of optical superposition.

Molinski Tadeusz F TF Biegelmeyer Renata R Stout E Paige EP Wang Xiao X Frota Mario L C ML Henriques Amelia T AT

Journal of natural products 20121226 3

Halisphingosines A (1) and B (2), modified long-chain sphingoid bases, from the marine sponge Haliclona tubifera collected in Brazil, were characterized after conversion to their N-Boc derivatives. The 2R,3R,6R configuration of halisphingosine A, a compound first reported from Haliclona sp. from South Korea, was confirmed using a novel CD approach: deconvolution of exciton coupling from mono- and trinaphthoyl derivatives obtained by derivatization of the natural product. The sensitive CD deconvo ...[more]

PMID: 23268569

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