Abstract
Chromatographic behavior of a series of N-methylated tetra and octapeptides on a reversed-phase sorbent was studied considering the information obtained on these compounds by NMR spectroscopy. The modified tetrapeptides were derived from GFFY-NH 2, GFFF-NH 2 and GFFH-NH 2 primary structures by N-methylation at various peptide bond positions. Similarly, the N-methylated octapeptides were based on TPK(Pac)T C-terminally elongated forms of GFFY and GFFF. It was found that many studied N-methylated peptides provide broad peaks as a consequence of cis/ trans isomerism of the R 1CO N(CH 3)R 2 peptide bond. The extent of the peak spreading depends on the following important factors: the nature of the surrounding amino acid residues, the location of the modified peptide bond within the peptide chain, temperature, and mobile phase flow-rate. All these aspects were critically evaluated. Nearly complete separation of the individual conformers of GF(NMe)FY-NH 2 was obtained applying fast chromatography on short column packed with 20–30 μm reversed-phase sorbent.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.