*2.2. Equipment*

All the 1H NMR (500.17) experiments were performed on a Bruker Avance III 500 NMR spectrometer (Bruker Biospin, Karlsruhe, Baden-Württemberg, Germany) with 256 or 512 scans and spectral windows of 20 ppm. The inaccuracy of the 1H NMR chemical shift measurement relative to the solvents (D2O and DMSO) was found to be ±0.01 ppm. The UV-Vis spectra were recorded in the range of 190–1200 nm on a JASCO V-770 spectrophotometer (Tokyo, Japan). The fluorescence spectra were recorded in the range of 430–770 nm on a Shimadzu RF 5301PC Spectrofluorimeter (Kyoto, Japan). The quantumchemical calculations were performed using v.4.2.1 of the ORCA program system [29]. The Density-functional Theory (DFT) method with the CAM-B3LYP hybrid functional and 3–21 basis set was used to optimize the compound ground state. The pH was monitored

by an Electroanalytical Analyzer (Type OP-300, Radelkis) ion meter. Elemental analyses were performed on a Flash EA 1112 analyzer. The mass spectra were obtained on a Shimadzu Biotech Axima Confidence Maldi TOF mass spectrometer of Kratos Analytical Limited-Great Britain, Manchester (with methanol as the solvent). The infrared analysis of the solid porphyrins was done on a VERTEX 80 V infrared Fourier-spectrophotometer (Ettlingen, Germany) with KBr pellets in the range of 4000–400 cm<sup>−</sup>1. The thermogravimetric analysis (TG) and differential thermal analysis (DTA) were recorded on a TG 209 F1 Iris thermomicrobalance (Netzsch, Germany) with dry samples at the heating rate of 10 C min−<sup>1</sup> in an argon atmosphere in the range from room temperature to 900 ◦C. The Electron Paramagnetic Resonance (EPR) spectra of solutions in water were recorded on an EPR 10-MINI spectrometer (St. Petersburg) with an operating frequency of 9.45 GHz. The magnetic field was calibrated using a standard DPPH (diphenylpicrylhydrazyl) sample.
