Sinefungin is an antibiotic and a close structural analog of S-adenosylmethionine, a co-factor for a vast number of enzymes. Sinefungin is one of a class of natural products containing both nucleoside and amino acid moieties.
Sinefungin is a conformationally complex molecule. Because the sinefungin molecule consists of a planar adenine ring capable of both syn and anti orientation with respect to a conformationally mobile ribose ring and a flexible amino acid side chain, it has a wide range of conformational features that may be related to its bioactivity.
Both lD and 2D F1NMR methods were used to evaluate vicinal proton coupling constants in order to determine probable dihedral angles about the C(2')-C(3') bond of the ribose ring and the C(α)-C(β), C(β)-C(γ), C(γ)-C(δ) and C(4') and C(5') dihedral angles of the amino acid side chain for proton spectra taken above pH 9.4. At this pH sinefungin is conformationally less flexible than S-adenosylmethionine. Overlapping resonances a detailed conformational analysis of sinefungin below pH 9.4. Most interesting was the discovery that the H(5') and H(5") resonances have the same chemical shift in acidic solutions so that valuable coupling constant information is lost. MM2 calculations were consistent with NMR results.
| Identifer | oai:union.ndltd.org:pacific.edu/oai:scholarlycommons.pacific.edu:uop_etds-3292 |
| Date | 01 January 1995 |
| Creators | Zhong, Muning |
| Publisher | Scholarly Commons |
| Source Sets | University of the Pacific |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | University of the Pacific Theses and Dissertations |
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