New photochemical properties of azidoaniline and ciprofloxacin.

There is a trend to find new ways of using photocatalysis in order to synthesize valuable products or to control or track live processes with special fluorescence-based molecular probes. The paper presents some results concerning new photochemical properties of para-azidoaniline, its 7-nitrobenzofurazan (NBD) derivative and ciprofloxacin derivatives. Ciprofloxacin (CPF) emits blue fluorescence as well as generates free radicals during photolysis. Its hydrophobic derivatives can be used as fluorescent photoinitiators showing antimicrobial properties. It was found out that the CPF itself, N-hexanoyl (CPF-Hex) and some other derivatives of ciprofloxacin exhibit the properties of a photoinitiator for polymerization under UV light (365 nm) on the model system of aqueous alcoholic solutions of acrylamide and N,N'-methylene bis-acrylamide, and that part of CPF-Hex molecule is capable of binding with the polymer chain covalently. A reaction between nitrobenzoxadiazole derivative of para-azidoaniline (NBD-azidoaniline) and hexyne-1 was studied. NBD-compounds can fluoresce, hence they are potentially applicable as molecular probes and for disease diagnostics, but their photochemistry wasn’t studied comprehensively. Eventually, the mixture of NBD-azidoaniline and hexyne-1 yielded the yellow fluorescent product under 365 nm UV light, whereas copper-catalyzed reaction gave a purple compound. Azidoaniline photolysis was studied in acetonitrile and methanol using UV-Vis spectroscopy resulted in monitoring of a new red fluorescent product formation in the first case. Elucidation of the processes might allow developing new molecular probes and photodynamic therapy agents. The work was supported GSPR (Belarus) № 20210560.