Formation, characterization, aggregation, fluorescence and antioxidant properties of novel tetrasubstituted metal-free and metallophthalocyanines bearing (4-(methylthio)phenoxy) moieties

Abstract

The synthesis and characterization of peripherally tetra 4-(methylthio)phenoxy substituted metal-free(2), Zn(II) (3) and Co(II) (4) phthalocyanine derivatives were reported. These newly synthesized phthalocyanine derivatives showed the enhanced solubility in organic solvents and they were characterized by a combination of elemental analysis, FTIR, H-1 NMR, C-13 NMR, UV-vis and MALDI-TOF/MS spectral data. Their aggregation properties were investigated in THE by UV-vis and fluorescence. These metal-free and metallophthalocyanine compounds were also evaluated for their total antioxidant abilities by using three different antioxidant methods such as 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging, ferrous ion chelating and reducing power activity. All tested compounds showed radical scavenging activity. The highest radical scavenging activity was found from cobalt phthalocyanine (4) compound respectively. IC50 values of the compounds and standards (BHT and Trolox) were also determined. The results showed that the compound 4 had the highest antioxidant activity among all tested compounds including standards. The tested phthalocyanine compounds had ferrous ion chelating activity. In addition, they showed very high reducing power. All tested compounds had higher reducing power than the standards such as ascorbic acid and BHT. The present study shows that the synthesized tetra phthalocyanine [M: 2H(2), Zn(II)(3), Co(lI)(4)] with four peripheral 4-(methylthio) phenoxy compounds have the effective antioxidant properties that can be used as antioxidant agents. (C) 2017 Elsevier B.V. All rights reserved.