Abstract
The amino acid derivative [H-Lys{Ru(bipy)2m}-cyclenH2](PF6)5 (7; Lys = lysine, bipy = 2,2′-bipyridyl, m = 4-carbonyl-4′-methyl-2,2′-bipyridyl, cyclen = 1,4,7,10-tetraazacyclododecane) has been synthesized. A modular approach was taken which involves only standard amide-coupling methods well-known from peptide synthesis. Compound 7 is readily soluble in water. It contains a luminescent ruthenium ...
Abstract
The amino acid derivative [H-Lys{Ru(bipy)2m}-cyclenH2](PF6)5 (7; Lys = lysine, bipy = 2,2′-bipyridyl, m = 4-carbonyl-4′-methyl-2,2′-bipyridyl, cyclen = 1,4,7,10-tetraazacyclododecane) has been synthesized. A modular approach was taken which involves only standard amide-coupling methods well-known from peptide synthesis. Compound 7 is readily soluble in water. It contains a luminescent ruthenium chromophore and a cyclen ligand which serves as a binding site for metal ions. The emission of 7 is pH-independent but efficiently quenched by Cu2+ ions in a pH range of 6−7. Copper(II) binding is reversible upon protonation of the ligand at pH values below 6. In contrast, no significant spectral changes are observed with Zn2+ and Ni2+, respectively. Thus, 7 selectively recognizes copper(II) in aqueous solution under slightly acidic to neutral conditions. Unfortunately, applications at higher pH values are limited by metal-promoted hydrolysis of 7 under mildly basic conditions.
Altmetric