Investigation of Biological Activities of Tetra‐substituted Phthalocyanines Bearing Tetraethyleneglycol Monomethyl Ether Chains at Peripheral and Non‐peripheral Positions

Abstract

Abstract This study describes the synthesis and characterization of peripherally and non‐peripherally substituted copper(II) and cobalt(II) phthalocyanines bearing tetraethyleneglycol monomethyl ether chains. In addition, the metal‐free and zinc(II) phthalocyanine derivatives were prepared according to the referred procedure. All newly synthesized phthalocyanines were characterized using some spectroscopic techniques such as elemental analysis and fourier transform infrared, ultraviolet‐visible, and mass spectroscopies. The effects of solvent type and concentration on aggregation properties of phthalocyanines were studied, as well. The biological activities of a series of these peripherally and non‐peripherally tetra‐substituted phthalocyanines were investigated. The effects of the central metal ion and the position of the substituent on biological activities of phthalocyanines were also compared. When the antioxidant activities of the synthesized molecules were evaluated by the 2,2‐diphenyl‐1‐picrylhydrazyl method, 1,8/11,15/18,22/25‐tetrakis[2‐(2‐(2‐(2‐methoxyethoxy)ethoxy)ethoxy)ethoxy]phthalocyaninatocobalt(II) (63.17±0.012 %) showed the highest activity. The highest reducing power activity was obtained with the 2,9/10,16/17,23/24‐tetrakis[2‐(2‐(2‐(2‐methoxyethoxy)ethoxy)ethoxy)ethoxy]phthalocyaninatozinc(II) molecule. In the antibacterial activity studies using the disc diffusion method, 2,9/10,16/17,23/24‐tetrakis[2‐(2‐(2‐(2‐methoxyethoxy) ethoxy)ethoxy)ethoxy]phthalocyaninatocopper(II) exhibited the highest inhibition activity on both gram negative (18±0.23 mm) and gram positive (23±0.07 mm) strains. On the other hand, 2,9/10,16/17,23/24‐tetrakis[2‐(2‐(2‐(2‐methoxyethoxy)ethoxy) ethoxy)ethoxy]phthalocyaninatozinc(II) and 1,8/11,15/18,22/25‐tetrakis[2‐(2‐(2‐(2‐methoxyethoxy)ethoxy)ethoxy)ethoxy]phthalo‐cyaninatozinc(II) compounds presented hemolytic activity against sheep blood in the hemolytic activity studies. The results confirmed that the synthesized molecules demonstrated average antioxidant activity compared to standard antioxidants. 2,9/10,16/17,23/24‐Tetrakis[2‐(2‐(2‐(2‐methoxyethoxy)ethoxy)ethoxy)ethoxy]phthalo‐cyaninatocopper(II), 2,9/10,16/17,23/24‐tetrakis[2‐(2‐(2‐(2‐methoxy ethoxy)ethoxy)ethoxy)ethoxy]phthalocyaninatozinc(II) and 1,8/11, 15/18,22/25‐tetrakis[2‐(2‐(2‐(2‐methoxyethoxy)ethoxy)ethoxy) ethoxy]phthalocyaninatozinc(II) complexes could remarkably inhibit S. aureus and CuPc‐1 complex E. coli growth.