title: 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.
authors.affiliation: Department of Chemistry and Biochemistry, University of California, San Diego, La Jolla, California 92093-0358, United States.
authors.forename: Brandon I
authors.initials: BI
authors.lastname: Morinaka
authors.forename: Tadeusz F
authors.initials: TF
authors.lastname: Molinski
mesh_terms: D000470:Alkaloids / Q000737:chemistry* / Q000302:isolation & purification*; D000588:Amines / Q000737:chemistry / Q000302:isolation & purification; D000818:Animals; D001444:Bahamas; D002942:Circular Dichroism; D008958:Models, Molecular; D015394:Molecular Structure; D019906:Nuclear Magnetic Resonance, Biomolecular; D010880:Piperidines / Q000737:chemistry* / Q000302:isolation & purification*; D011161:Porifera / Q000737:chemistry*
chemical_list: D000470:Alkaloids; D000588:Amines; D010880:Piperidines; C558364:xestoproxamine A; C558365:xestoproxamine B; C558366:xestoproxamine C