Modern approaches to the synthesis and prospects for the use of cyanine dyes containing functional groups in the N-substituents

Methods for the synthesis of mono-, tri-, penta- and heptamethine cyanine dyes containing functional groups in N-substituents are considered. Approaches suitable for the preparation of both symmetrical and unsymmetrical cyanine dyes are presented. Examples of the practical use of this type of cyanine dyes as fluorescent labels and probes in biology and medicine, as well as of components of photoactive supramolecular structures, photosensitizers and photo- and electroluminescent materials are given. The bibliography includes 106 references.