Contribution No. 131 from Molecular Biophysics Unit, Indian Institute of Science, Bangalore, India.
STEREOCHEMICAL STUDIES ON CYCLIC PEPTIDES
Part X. Conformational Analysis of Hydrogen Bonded Cyclic Pentapeptides*
Article first published online: 12 JAN 2009
© 1979 Munksgaard, Copenhagen
International Journal of Peptide and Protein Research
Volume 13, Issue 3, pages 353–362, March 1979
How to Cite
MANJULA, G. and RAMAKRISHNAN, C. (1979), STEREOCHEMICAL STUDIES ON CYCLIC PEPTIDES. International Journal of Peptide and Protein Research, 13: 353–362. doi: 10.1111/j.1399-3011.1979.tb01892.x
- Issue published online: 12 JAN 2009
- Article first published online: 12 JAN 2009
- Received 9 August, accepted for publication 29 September 1978
- cyclic pentapeptide;
- hydrogen bond;
- ring closure;
Conformational aspects of 4 → 1 hydrogen bonded cyclic pentapeptides are considered in this paper from the point of view of “contact criteria” and potential energy calculations. Three types of such hydrogen bonded conformations, designated A1, A2 and B, are possible, involving some amount of strain on the bond angles. The energy of hydrogen bonded cyclopentaglycyl is somewhat less than that of the five-fold symmetrical conformation. The stereochemical feasibility of introducing l- and d-alanyl residues in these structures has also been studied and the possible types for different sequences of alanyl residues have been determined. The results are discussed further in the light of the limited data available from crystal structure and nuclear magnetic resonance studies on cyclic pentapeptides.