Novel phthalocyanines bearing 1,2,4-triazole substituents linked by sulfur bridges and investigating the photophysical and singlet oxygen generation properties

The new phthalocyanines, H2Pc (4), ZnPc (5), and PbPc (6) linked to 1,2,4-triazole groups were synthesized and characterized. Additionally, the performance of these compounds in photodynamic therapy was investigated. The new metal-free phthalocyanine (H2Pc) (4) was directly obtained from new phthalonitrile (3) without the addition of any metal salt. This original nitrile compound (3) was converted to several new metallic phthalocyanines (Pcs) such as Zn(II) (5), and Pb(II) (6) using appropriate metal salts. Newly prepared phthalocyanines (4-6) were examined for their photodynamic therapeutic (PDT) properties as photosensitizers (PS), yielding significant findings. The structures of these newly obtained compounds were elucidated using spectroscopic techniques such as MALDI-TOF MS, FT-IR, UV-vis, 1H NMR and 13C NMR.