Antimicrobial and antioxidant properties of novel octa-substituted phthalocyanines bearing (trifluoromethoxy) phenoxy groups on peripheral positions

This study presents a novel phthalonitrile derivative (2) bearing (trifluoromethoxy)phenoxy groups in 4,5 positions. Cyclotetramerization of (2) in N,N-dimethylaminoethanol (DMAE) gave a series of peripherally octa-substituted metallophthalocyanines (3-Zn, 3-Co and 3-Cu). The newly synthesized phthalocyanines have been characterized by a combination of various spectroscopic techniques. Effects of solvent nature on aggregation behavior of 3-Zn were studied using different solvents such as acetone, CHCl ₃ and dichloromethane (DCM). In addition, the aggregation behavior of the phthalocyanine complex 3-Zn was examined in DCM at different concentrations ranging from 4 × 10-6-14 × 10-6 M. Antimicrobial activities of synthesized compounds were tested by using the thin layer chromotography (TLC)-direct bioautography and disk diffusion methods. In both assays, the molecules showed activity on the tested Gram (+) bacteria. Antioxidant activities of the molecules, on the other hand, were determined by using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging method and a reducing power assay. The highest activity was obtained with 3-ZnPc for both methods.