Collect. Czech. Chem. Commun. 1980, 45, 482-490

13C nuclear magnetic resonance study of cyclodipeptides containing 13C enriched hydrophobic amino acids

Jaroslav Vičara, François Pirioub, Pierre Fromageotb, Karel Bláhac and Serge Fermandjianb

a Institute of Chemistry, Medical Faculty, Palacký Univeristy, 775 15 Olomouc, Czechoslovakia
b Service de Biochimie, Centre d'Etudes Nucléaires de Saclay, 911 90 Gif-sur-Yvette, France
c Institute of Organic Chemistry and Biochemistry, Czechoslovak Academy of Sciences, 166 10 Prague, Czechoslovakia


The diastereoisomeric pairs of cyclodipeptides cis- and trans-cyclo(Ala-Ala), cyclo(Ala-Phe), cyclo(Val-Val) and cyclo(Leu-Leu) containing 85% 13C enriched amino-acid residues were synthesized and their 13C-13C coupling constants were measured. The combination of 13C-13C and 1H-1H coupling constants enabled to estimate unequivocally the side chain conformation of the valine and leucine residues.