Synthesis and photophysical properties of meso-aminophenyl-substituted heptamethine dyes as potential leads to new contrast agents

The series of rigid meso-aminophenyl-substituted heptamethine dyes presented herein exhibit surprising fluorescence properties, demonstrating larger Stokes shifts when compared with both structurally similar rigid meso-chlorophenyl and linear heptamethine dyes. Based on their photophysical properties, these are of considerable importance to the development of contrast agents, within biology and medicine. © 2019 The Authors. Coloration Technology © 2019 Society of Dyers and Colourist