Zinc(II) phthalocyanine substituted by sulfonamide derivative: Photophysical and photochemical properties

Synthesis of two different new compounds, (E)-4-((2‑hydroxy-3‑methoxy-5-nitro benzylidene)amino)-N-(pyridine-2-yl)benzenesulfonamide 1, (E)-4-((2-(3,4-dicyanophenoxy )-3‑methoxy-5-nitrobenzylidene)amino)-N-(pyridine-2-yl)benzenesulfonamide2and 2(3),9(10),16(17),23(24)-tetrakis-[(E)-4-((3‑methoxy-5-nitro-2-(λ1-oxidanyl)benzylidene) amino)-N-(pyridine-2-yl)benzene sulfonamid] zinc(II) phthalocyanine complex 3 was carried out. Their structures were characterized by spectroscopic methods such as Fourier transform infrared, Proton nuclear magnetic resonance, Carbon-13 nuclear magnetic resonance, Ultraviolet-visible, Fluorescence, Matrix-assisted laser desorption/ionization, Time-of-flight mass (except compounds 1 and 2), as well as Elemental analysis. The spectroscopic, photophysical, and photochemical properties of zinc(II) phthalocyanine complex 3, substituted with new benzenesulfonamide derivatives containing different functional groups, were explored in dimethylsulfoxide to determine its usability as a photosensitizer for photodynamic therapy. The effects of the presence of tetra-substituted new benzenesulfonamide groups from the peripheral positions of the zinc(II) phthalocyanine ring on the spectroscopic, photophysical, and photochemical properties were investigated and these properties were compared with the properties of the substituted and unsubstituted zinc(II) phthalocyanines. As a photosensitizer for photodynamic therapy, this new phthalocyanine 3 has well solubility in different kinds of solvents without aggregation sufficient fluorescence properties, ability to produce singlet oxygen, and photostability under appropriate light irradiation.