Abstract:
The stability of cyclic peptides and their self-assembling ability is an important aspect
in the DNA recognition studies. Functionalization of cyclic peptides with nuclear
bases may serve the purpose of mimicking and interacting with the DNA single
strand. Stacking of the cyclic peptides after functionalzation may develop steric
hinderance. L-Lysine, with side chain amino group, was selected to avoid these steric
factors. Differently-protected L-lysine was transformed into its respective β-analogue
using Arndt Eistert synthesis. These β-amino acids were utilized to synthesize cyclic
β-tripeptide scaffolds through a multistep sequence. The scaffolds after deprotection
were subjected to functionalization with the selected nuclear bases (adenine, thymine,
cytosine and guanine) after conversion to their acetic acid derivatives. The
nucleobase-functionalized cyclic β-tripeptide scaffolds were completely deprotected,
purified by RP-HPLC and characterized by ESI and HRMS.
