Estimating the Ground and Excited State Dipole Moments of Levofloxacin and Norfloxacin Drugs Using Solvatochromic Effects and Computational Work

Kinfe Woldegiorges,Abebe Belay,Tamirat Abebe,Alemu Kebede,Jose M Pedrosa

doi:10.1155/2021/7214182

Kinfe Woldegiorges, Abebe Belay + Show 3 more

Open Access

https://doi.org/10.1155/2021/7214182

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Abstract

Levofloxacin (LVF) and norfloxacin (NRF) are a group of fluoroquinolone antibiotics, broad spectrum used to treat various infections caused by many bacterial species. The drugs contain functional groups which control the type and degree of interaction with different solvents. In this research, the ground and excited state dipole moments of LVF and NRF drugs were estimated using solvatochromic effects and computational work. The dipole moments were estimated from absorption and emission spectra in polar and nonpolar solvents using Bakhshiev’s, Kawski–Chamma–Viallet, Lippert–Mataga, and Reichardt models. The results indicated the emission spectra are more strongly affected by solvent polarity than the absorption spectra. The calculated excited state dipole moment is larger than that of the ground state, indicating that the probe compounds are significantly more polarized in the excited state than in the ground state. From computational work, the HOMO-LUMO energy band gap, the dipole moments, electron charge density distribution, and oscillator strength were determined using the semiempirical MP6 method, DFT-B3LYP-6-31G, and DFT-B3LYP-3-21G employing Gaussian 09 software. In general, larger dipole moments were obtained by computation rather than from experiments due to the absence of solvent effects.

Highlights

Levofloxacin (LVF) and norfloxacin (NRF) are a group of fluoroquinolone antibiotics with a broad medicinal spectrum, active against Gram-negative and Gram-positive bacteria
Different studies indicated that the polarity parameters of a drug originated from its chemical structure and functional groups attached to the compound [2]
The physical and chemical behaviors of the drugs are altered in solvents [3, 4]. e functional groups that exist in drugs are controlling the type and degree of interaction with solvents [5, 6]

Summary

Introduction

Levofloxacin (LVF) and norfloxacin (NRF) are a group of fluoroquinolone antibiotics with a broad medicinal spectrum, active against Gram-negative and Gram-positive bacteria. State dipole moments of drugs from solvatochromic effects and computational work has great importance to reveal information on the electronic and geometrical structures of these drug molecules [2, 16]. It reflects the charge distribution in the molecule and is useful in parameterization in quantum chemical procedures [17]. The photophysical properties of some vitamins and other drugs were studied, to the best of our knowledge, the solvatochromic effect of LVF and NRF in polar and nonpolar solvents for the determination of ground and excited state dipole moments have not been investigated experimentally and theoretically. The photophysical properties of some vitamins and other drugs were studied, to the best of our knowledge, the solvatochromic effect of LVF and NRF in polar and nonpolar solvents for the determination of ground and excited state dipole moments have not been investigated experimentally and theoretically. erefore, in this research the ground and excited state dipole moment are estimated experimentally using Lippert–Mataga, Bakhshiev’s, Kawski–Chamma–Viallet, and Reichardt equations and computational work using DFT and semiempirical methods employing Gaussian 09 software

Theoretical Background

Materials and Methods

Results and Discussion