Studies on chalcone derivatives: complex formation, thermal behavior, stability constant and antioxidant activity

Area of Science:

• Coordination Chemistry
• Materials Science
• Computational Chemistry

Background:

• Chalcones are versatile organic compounds with diverse biological and chemical applications.
• Copper complexes often exhibit interesting catalytic and medicinal properties.
• Understanding ligand-metal interactions is crucial for designing new functional materials.

Purpose of the Study:

• To synthesize and characterize two novel chalcone derivatives: 3-[4'-dimethylaminophenyl]-1-(2-pyridyl) prop-2-en-1-one (DMAPP) and 3-(4'-diethylaminophenyl)-1-(2-pyridinyl) prop-2-en-1-one (DEAPP).
• To investigate the complexation of DMAPP and DEAPP with Cu(II) ions, determining their stoichiometry, stability constants, and structural properties.
• To evaluate the antioxidant activity and interaction modes of these chalcones with copper nanoparticles.

Main Methods:

• Synthesis and characterization of chalcones using IR, 1H NMR, and 13C NMR spectroscopy.
• UV-Visible spectroscopy and Job's method for determining complex stoichiometry and stability constants.
• Thermogravimetric analysis (TGA) for thermal decomposition studies.
• Molecular mechanics and dynamics simulations for structural optimization.
• DPPH radical scavenging assay for antioxidant activity evaluation.

Main Results:

• The mole fraction ratio for copper with DMAPP and DEAPP complexes was found to be 1:1.
• Stability constants (Kf) for Cu(II)-DMAPP and Cu(II)-DEAPP complexes were determined to be 9.9×10^4 and 5.2×10^4, respectively.
• DMAPP exhibited higher antioxidant activity compared to DEAPP.
• Semi-empirical studies indicated a higher dipole moment for DMAPP than DEAPP.
• The interaction of chalcones with copper nanoparticles was elucidated, and association constants were evaluated.

Conclusions:

• The synthesized chalcones (DMAPP and DEAPP) form stable complexes with Cu(II) ions.
• DMAPP demonstrates superior antioxidant potential and a higher dipole moment compared to DEAPP.
• The study provides insights into the structural, thermal, and interaction properties of these chalcone-copper complexes and their potential applications.