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Symplocin A, a linear peptide from the Bahamian cyanobacterium Symploca sp. Configurational analysis of N,N-dimethylamino acids by chiral-phase HPLC of naphthacyl esters.

ABSTRACT: The absolute stereostructures of the components of symplocin A (3), a new N,N-dimethyl-terminated peptide from the Bahamian cyanobacterium Symploca sp., were assigned from spectroscopic analysis, including MS, 2D NMR, and Marfey's analysis. The complete absolute configuration of symplocin A, including the unexpected D-configurations of the terminal N,N-dimethylisoleucine and valic acid residues, was assigned by chiral-phase HPLC of the corresponding 2-naphthacyl esters, a highly sensitive, complementary strategy for assignment of N-blocked peptide residues where Marfey's method is ineffectual or other methods fall short. Symplocin A exhibited potent activity as an inhibitor of cathepsin E (IC(50) 300 pM).

SUBMITTER: Molinski TF

PROVIDER: S-EPMC3694611 | biostudies-literature | 2012 Mar

REPOSITORIES: biostudies-literature

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Symplocin A, a linear peptide from the Bahamian cyanobacterium Symploca sp. Configurational analysis of N,N-dimethylamino acids by chiral-phase HPLC of naphthacyl esters.

Molinski Tadeusz F TF Reynolds Kirk A KA Morinaka Brandon I BI

Journal of natural products 20120223 3

The absolute stereostructures of the components of symplocin A (3), a new N,N-dimethyl-terminated peptide from the Bahamian cyanobacterium Symploca sp., were assigned from spectroscopic analysis, including MS, 2D NMR, and Marfey's analysis. The complete absolute configuration of symplocin A, including the unexpected D-configurations of the terminal N,N-dimethylisoleucine and valic acid residues, was assigned by chiral-phase HPLC of the corresponding 2-naphthacyl esters, a highly sensitive, compl ...[more]

PMID: 22360587

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