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Structures and solution conformational dynamics of stylissamides G and H from the Bahamian sponge Stylissa caribica.

ABSTRACT: Two new peptides, stylissamides G and H, were isolated from extracts of a sample of Stylissa caribica collected in deep waters of the Caribbean Sea. A single sample of S. caribica among a collection of 10 samples that were examined by LC-MS appeared to be a different chemotype from the others in that it lacked the familiar pyrrole-2-aminoimidazole alkaloids, stevensine and oroidin, and contained peptides of the stylissamide class. The structures of the title compounds were solved by integrated analysis of the MS and NMR spectra and chemical degradation. The solution conformation of stylissamide G was briefly examined by electronic circular dichroism and temperature-dependent (1)H NMR chemical shifts of amide NH signals, which supported a conformationally rigid macrocycle.

SUBMITTER: Wang X

PROVIDER: S-EPMC3993948 | biostudies-literature | 2014 Mar

REPOSITORIES: biostudies-literature

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Structures and solution conformational dynamics of stylissamides G and H from the Bahamian sponge Stylissa caribica.

Wang Xiao X Morinaka Brandon I BI Molinski Tadeusz F TF

Journal of natural products 20140227 3

Two new peptides, stylissamides G and H, were isolated from extracts of a sample of Stylissa caribica collected in deep waters of the Caribbean Sea. A single sample of S. caribica among a collection of 10 samples that were examined by LC-MS appeared to be a different chemotype from the others in that it lacked the familiar pyrrole-2-aminoimidazole alkaloids, stevensine and oroidin, and contained peptides of the stylissamide class. The structures of the title compounds were solved by integrated a ...[more]

PMID: 24576291

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