Abstract
A 220-MHz proton nuclear magnetic resonance study of the binding of Ni(II) and Co(II) acetylacetonates to retinyl-N-methyl Schiff's bases is presented. The study has yielded the magnitude and sign of spin densities at the carbon atoms in the π system of the 9-cis, 13-cis, and all trans isomers. From a comparison of the experimental results with molecular orbital calculations, a mechanism for transfer of spin from the metal to the retinyl Schiff's base and its subsequent delocalization down the polyene chain is provided.
Full text
PDF
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- JURKOWITZ L., LOEB J. N., BROWN P. K., WALD G. Photochemical and stereochemical properties of carotenoids at low temperatures. Nature. 1959 Aug 22;184:614–624. doi: 10.1038/184614a0. [DOI] [PubMed] [Google Scholar]
- Korver P. K., Kruk C., van der Haak P. J., Baas J. L., Huisman H. O. Vitamin A analogues. 3. Determination of the stereochemical configuration of some polyenes of the 4-thia-vitamin A series by NMR spectrometry. Tetrahedron. 1966 Jan;22(1):277–284. doi: 10.1016/0040-4020(66)80128-x. [DOI] [PubMed] [Google Scholar]
- Patel D. J. 220 MHz proton nuclear magnetic resonance spectra of retinals. Nature. 1969 Mar 1;221(5183):825–828. doi: 10.1038/221825a0. [DOI] [PubMed] [Google Scholar]
- Poincelot R. P., Millar P. G., Kimbel R. L., Jr, Abrahamson E. W. Lipid to protein chromophore transfer in the photolysis of visual pigments. Nature. 1969 Jan 18;221(5177):256–257. doi: 10.1038/221256a0. [DOI] [PubMed] [Google Scholar]
- Wiesenfeld J. R., Abrahamson E. W. Visual pigments: their spectra and isomerizations. Photochem Photobiol. 1968 Nov;8(5):487–493. doi: 10.1111/j.1751-1097.1968.tb05892.x. [DOI] [PubMed] [Google Scholar]