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Xestoproxamines A-C from Neopetrosia proxima. Assignment of absolute stereostructure of bis-piperidine alkaloids by integrated degradation-CD analysis.

ABSTRACT: The complete stereostructures of xestoproxamines A-C, from the Bahamian sponge Neopetrosia proxima, were assigned from spectroscopic analysis, including MS, 2D NMR, and integrated degradation-CD analysis. Two new CD application protocols are described for defining absolute configuration: one for allylic methyl groups in branched chains and a second for the heterocyclic core bis-piperidine with specific applicability to other members of this class alkaloids--known for their stereoheterogeneity--and tertiary cyclic amines in general.

SUBMITTER: Morinaka BI

PROVIDER: S-EPMC3957325 | biostudies-literature | 2011 Mar

REPOSITORIES: biostudies-literature

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Xestoproxamines A-C from Neopetrosia proxima. Assignment of absolute stereostructure of bis-piperidine alkaloids by integrated degradation-CD analysis.

Morinaka Brandon I BI Molinski Tadeusz F TF

Journal of natural products 20110222 3

The complete stereostructures of xestoproxamines A-C, from the Bahamian sponge Neopetrosia proxima, were assigned from spectroscopic analysis, including MS, 2D NMR, and integrated degradation-CD analysis. Two new CD application protocols are described for defining absolute configuration: one for allylic methyl groups in branched chains and a second for the heterocyclic core bis-piperidine with specific applicability to other members of this class alkaloids--known for their stereoheterogeneity--a ...[more]

PMID: 21341726

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