Synthesis, Characterization, and Pharmacological Activities of Copper(II) Complexes of Curcumin Derivatives

Background: Curcuma longa L is a herbaceous plant of zingiberaceae family. Curcumin and its derivatives possess a vast varieties of biological activities like antimicrobial, antioxidant, anti-inflammatory, antimalarial, antirheumatic etc. Looking into the biological significance of curcumin and its derivatives, we have decided to synthesize novel derivatives of curcumin and their coordinated Copper (II) complexes and evaluate their pharmacological activities like antioxidant, antibacterial etc. Methods: Targeted derivatives of curcumin were prepared in good yield (95%) by the condensation reaction of carbohydrazide(1), Curcumin(2), in presence of copper salts using classical heating methods in the presence of absolute ethanol. Results: The targeted derivatives of Curcumin were evaluated for their collaborative antimicrobial activity against gram-positive and gram-negative bacterial strains. The zone of inhibition was measured by considering the disc diffusion method. In-vitro minimum inhibitory concentrations of targeted compounds were measured using the broth micro-dilution method. In addition to this, the invitro antioxidant activity of target compounds was also evaluated by adopting the DPPH method using ascorbic acid as a standard substance. Most of the compounds showed fascinating antibacterial and antioxidant activities as a contrast to pure curcumin. Conclusion: In conclusion, the present work explains the synthesis, characterization and evaluation of biological activities of novel derivatives of curcumin and their coordinated Copper (II) complexes. All the targeted compounds were screened for their pharmacological evaluation against selected human pathogenic bacteria. Antioxidant activity of the synthesized compounds was also evaluated against DPPH and ascorbic acid standard substances. Among the designed molecules, most of the compounds showed fascinating antibacterial and antioxidant activities as compared to pure curcumin.