Synthesis of substituted pyrimidine hydrazine acids (PHA) and their use in peptide recognition

Abstract

Substituted pyrimidine-hydrazine-acids (PHA) were prepared from orotic acid in five synthetic steps and high yields. Their geometry of hydrogen bond acceptor and donor sites make them suitable for the molecular recognition of peptide β-sheets. In non-protic solvents the PHA unit emits at around 420 nm after irradiation at 281 nm. The emission intensity decreases upon peptide binding and signals the binding event. Peptides consisting of PHAs and natural amino acids or a turn structure motif were prepared. The investigation of the intramolecular binding pattern by NMR spectroscopy revealed the expected interaction of the PHA and peptide β-sheet.