Synthesis and evaluation of a new colorimetric and ratiometric fluorescence probe for copper ions

Synthesis and spectroscopic evaluation of compounds 3a, 3b and 4 reveal that cone conformer of 25,27-bis(o-aminothiophenyl propyloxy) -tetra-p-tert-butylcalix[4]arene 3a can function as a highly selective ratiometric and colorimetric fluorescence probe for copper ions.