Abstract
It is shown that by considering the 13C-C-C-H coupling constant between the α-CO2- and the β-protons in amino-acids it is possible to obtain side-chain conformational information concerning the rotamer populations which is not available from studies of H-H coupling constants alone.
| Originalsprog | Engelsk |
|---|---|
| Tidsskrift | Journal of the Chemical Society, Chemical Communications |
| Udgave nummer | 12 |
| Sider (fra-til) | 465-466 |
| Antal sider | 2 |
| ISSN | 0022-4936 |
| DOI | |
| Status | Udgivet - 1974 |
| Udgivet eksternt | Ja |
Bibliografisk note
Funding Information:CHEM. COMM., 1974 tative values for the rotamer populations from 1sC-C-C-H spin coupling constants alone. Although this method is a general one for the study of side-chain conformations in amino-acids, the above results were obtained on concentrated solutions (ca. l~) with 13C in natural abundance. To extend this method to larger molecules such as hormonal peptides it will probably be necessary to synthesise molecules enriched with 13C at the peptide carbonyl groups to overcome the sensitivity problem. P.E.H. acknowledges the support of a Royal Society Exchange Fellowship. (Received, 13th March 1974; Corn. 293.) G. C. K. Roberts and 0. Jardetzky, Adv. Protein Chem., 1970,24, 447; V. F. Bystrov, S. L. Portnova, V. I. Tsetlin. V. T. Ivanov, and Y. A. Ovchinnikov, Tetrahedron, 1969, 25, 493. a R. Wasylishen and T. Schaefer, Canud. J. Chem., 1972,50,2710; R. U. Lemieux, T. L. Nagabhushan, and B. Paul, ibid., p. 773;J. A. Schwarcz and A. S. Perlin, ibid., p. 4667.* J. Feeney, G. C. K. Roberts, J. P. Brown, A. S. V. Burgen, and H. Gregory, J.C.S. Perkin 11, 1972, 601.