Porphyrazine Structures with Electron-Withdrawing Substituents as the Base for Materials for Photonics and Biomedicine

Abstract

A survey of the studies dealing with the development of new porphyrazine type tetrapyrrole dyes promising for the application in photonics and biophotonics is presented. An original synthetic approach to the template assembly of the porphyrazine macrocycle at room temperature in high yield has been proposed. A porphyrazine macrocycle containing eight nitrile groups at the periphery has been prepared for the first time. The replacement of four nitrile groups in the macrocycle by aryl groups has been found to generate a unique porphyrazine structure demonstrating a fluorescent molecular rotor behavior, i.e., a strong dependence of fluorescence parameters (quantum yields and lifetimes) on the viscosity of the medium. Some aspects of possible applications of the obtained compounds in biophotonics are described. Good prospects for the use of these compounds as efficient agents for tumor diagnosis, sensitizers for photodynamic therapy, and probes for intracellular viscosity are outlined.