Novel triazole containing zinc(II)phthalocyanine Schiff bases: Determination of photophysical and photochemical properties for photodynamic cancer therapy

A simple and efficient synthesis of novel zinc(II) phthalocyanines bearing triazole moieties was described. The synthetic approach for preparation of the phthalocyanines 1 and 13 was achieved by Schiff base condensation reaction of phthalocyanine tetracarbaldehydes 3 and 12 with 4-amino-4H-1,2,4-triazole 5 in tetrahydrofuran in reasonable yields. The photophysical and photochemical properties of the compounds 1, 3, 12 and 13 were recorded only in DMSO. The singlet oxygen generation ability of the targeted phthalocyanine Schiff bases were investigated in an attempt to understand their potential for photodynamic therapy (PDT) activity. Moreover, in vitro PDT application was performed against the MCF-7 and MDA-MB-231 invasive breast carcinoma cell lines. Preliminary assay showed that the compounds 1 and 13 possessed the phototoxicity and cytotoxicity, with a maximum of 30% MCF-7 cells dead following light irradiation. It was also revealed that the targeted phthalocyanines possess promising characteristic as photosensitizer towards tumor cells