Synthesis and spectrophotometric studies of CT complex between 1,2-dimethylimidazole and picric acid in different polar solvents: exploring antimicrobial activities and molecular (DNA) docking

ABSTRACT

The charge transfer complex (CT complex) formed in ethanol with 1,2-dimethylimidazole (DMI, donor) and picric acid (PA, π- acceptor) at room temperature (RT) and spectrophotometric studies have been performed in various solvents. CT complex was characterised using different analysis like – ¹H NMR, FTIR spectra and UV-vis spectra which designates that CT interaction is connected to proton relocation to DMI from PA followed by the formation of N⁺–H···O⁻ type bonding. Spectrophotometric data helps in calculating various physical parameters (such as K_CT, ε_CT, ΔG^o, I_D, R_N, E_CT, μ_EN and f) were also obtained through Benesi–Hildebrand equation. From these parameters it was observed that [(DMIH)⁺(PA)⁻] formation dependents on type of solvent used. 1:1 stoichiometry of [(DMIH)⁺(PA)⁻] was found by a straight-line method. Antimicrobial activity of the CT complex was demonstrated. Molecular docking study give us the information of binding of [(DMIH)⁺(PA)⁻] with B-DNA which has substantial application for drug designing.

KEYWORDS:

• Charge transfer
• UV-visible spectroscopy
• ¹H NMR
• antimicrobial studies
• molecular docking

Acknowledgements

The authors wish to thank the Chairman, Department of Chemistry AMU, Aligarh, India for providing research facilities. Sonam Shakya, appreciatively thanks the UGC, New Delhi for financial assistance through the scholarship and contingency. I. M. Khan also thanks DST-FIST & UGC DRS-SAP(II) programmes for providing necessary research facilities.

Disclosure statement

No potential conflict of interest was reported by the authors.