Background: Peripherally tetrasubstituted cobalt(II), titanium(IV), manganese(III) phthalocyanines carrying redox-active metal centers were previously synthesized. Metallophthalocyanines (MPcs) have exhibited the potential to use in
medicinal applications due to biological activities such as antibacterial, antioxidant and enzyme inhibition.
Objective: This study aim was to evaluate the previously synthesized metallophthalocyanines in terms of carbonic anhydrase
inhibition, antioxidant, and antimicrobial activities.
Methods: Carbonic anhydrase activity was assayed by following esterase activity. The antibacterial activity was tested by
the disc diffusion method against eight bacteria. The antioxidant activity was determined by two common methods, 2,2-
diphenyl-1-picrylhydrazyl (DPPH•) radical scavenging and ferric ion (III) reducing/antioxidant power (FRAP) assays.
Results and Discussion: In this study, the inhibition potential of the metallophthallocyanines against carbonic anhydrase
(CA) enzyme, which is important for treatments of many disorders, was evaluated. The metallophthalocyanines showed
high CA inhibitory activity with IC50 values in the range of 74-317 nM, which was similar or better when compared with the
standard CA inhibitors sulfanilamide and acetazolamide. In addition, antibacterial and antioxidant activities were determined. The metallophthallocyanines exhibited moderate antibacterial activity, especially against S. aureus and S. epidermis.
The antioxidant activities of the compounds in both tests were quite high even exceeding the standards Trolox and BHT,
with SC50 values of 0.0048-0.0257 and TEAC values of 1143.3-1543.7 µM, which meant 2 to 73 fold better activity.
Conclusion: In conclusion, all three metallophthalocyanines exhibited excellent carbonic anhydrase and antioxidant potential and have deserved further interest in the synthesis of new derivatives.