Synthesis and NMR elucidation of novel pentacycloundecane-based peptides.
The synthesis and NMR elucidation of two novel pentacycloundecane (PCU)-based peptides are reported. The PCU cage amino acids were synthesised as racemates and the incorporation of the cage amino acid with (S)-natural amino acids produced diastereomeric peptides. The diastereomeric 'cage' peptides were separated using preparative HPLC and the NMR elucidation of these PCU containing peptides are reported for the first time. The (1)H and (13)C NMR spectra showed series of overlapping signals of the cage skeleton and that of the peptide, making it extremely difficult to resolve the structure using one-dimensional NMR techniques only. The use of two-dimensional NMR techniques proved to be a highly effective tool in overcoming this problem.
Altaib
Mohamed S
MS
School of Chemistry, University of KwaZulu-Natal, Durban 4001, South Africa.
Arvidsson
Per I
PI
Govender
Thavendran
T
Maguire
Glenn E M
GE
Makatini
Maya
M
Onajole
Oluseye K
OK
Kruger
Hendrik G
HG
D000473:Alkanes / Q000737:chemistry* / Q000528:radiation effects*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D010455:Peptides / Q000138:chemical synthesis*
D000473:Alkanes; D010455:Peptides; C022884:undecane