Cátia I. C. Esteves, M. Raposo, S. Costa
Nov 1, 2016
Citations
0
Influential Citations
15
Citations
Journal
Dyes and Pigments
Abstract
Abstract Novel fluorescent 4,5-diarylimidazolyl-phenylalanines 3a - d were prepared by reaction of N - tert -butyloxycarbonyl-4-formylphenylalanine methyl ester and appropriate (hetero)aromatic diones. The photophysical properties of these new unnatural amino acids were evaluated by UV–Vis absorption and fluorescence spectroscopy in solvents of different character and aqueous mixtures with acetonitrile. They were evaluated as novel amino acid based fluorimetric chemosensors for ions through spectrophotometric and spectrofluorimetric titrations with biologically and analytically important anions and cations such as F − , OH − , Cu 2+ and Fe 3+ . The results indicate that there was a strong interaction through the donor N, O and S atoms at the side chain, especially for 4,5-di(furan-2′-yl)imidazolyl-phenylalanine 3a and 4,5-di(thiophen-2′-yl)imidazolyl-phenylalanine 3b with Cu 2+ and Fe 3+ , in a 1:1 complex stoichiometry. The photophysical and metal ion sensing properties of these amino acids suggest that they can be suitable for incorporation into chemosensory peptidic frameworks.