Synthesis and characterization of novel quatemized 2, 3-(diethylmethylamino)phenoxy tetrasubstituted Indium and Gallium phthalocyanines and comparison of their antimicrobial and antioxidant properties with different phthalocyanines

In this work, we describe the synthesis and characterization of tetra-substituted 2,9(10),16(17),23(24)-tetrakis-[3-(diethylmethylamino)phenoxy) phthalocyaninatochlorogallium (III) tetraiodide and 2,9(10),16(17),23(24)-tetrakis-[3-(diethylmethylamino)phenoxy) phthalocyaninatochloroindium (III) tetraiodide and comparision of their antioxidant and antimicrobial activities with previously synthesized metallo- or metal-free octa-substituted phthalocyanines bearing diethylaminophenoxy groups at peripheral positions. Antioxidant activities of the compounds were investigated by using DPPH free radical scavenging assay, beta-carotene/linoleic acid bleaching assay and reducing power assay and no significant difference was observed between metal-containing and metal-free phthalocyanine compounds. Disc diffusion and macro dilution methods were used to determine the antimicrobial activities of the PCs on Gram-negative and Gram-positive bacteria and newly synthesized tetra-cationic gallium (PC6) and indium (PC7) phthalocyanines showed antimicrobial activity against all tested microorganisms. Antibacterial activity of neutral compounds was considerably lower or even negligible than that of cationic ones.