Colorimetric macrocyclic anion probes bearing nitrophenylurea and nitrophenylthiourea binding groups

Two novel molecular probes bearing two urea (sensor 1) or thiourea (sensor 2) groups (as anion recognition site) coupled with a nitrophenyl group (chromogenic unit) were synthesized and evaluated according to the binding site-signaling subunit approach. The behavior of these different compounds toward metal ions (Co2+, Ni2+, Cu2+, Zn2+, and Cd2+) and anions (F−, Cl−, Br−, I−, image, image, CN−, OH−, CH3COO−, and image) was investigated by UV–vis spectroscopy in DMSO.