Computational Studies of the Role of Substituents on the Reactivity and Biological Activities of Naphthoic Acid

Azeema Munir,Muhammad Abid Zia,Sidra Ayaz,Anwar-Ul-Haq Ali Shah,Afzal Shah,Faiza Jan Iftikhar,Tayyaba Kokab

doi:10.11648/j.ajpc.20211003.12

Azeema Munir, Muhammad Abid Zia + Show 5 more

Open Access

https://doi.org/10.11648/j.ajpc.20211003.12

Copy DOI

Abstract

Substituents play a major role in influencing the reactivity and biological activity of aromatic compounds. Substituents affect the conductivity of molecular electronic and photoresponsive switches, light harvesting dye-sensitized solar cells and organic electroluminescent devices. A number of quantum mechanical methods corresponding to stabilization energy, charge of substituent active region, energy dispersive analysis, and molecular electrostatic potential help in the description of substituent effect in aromatic systems. In the present work we carried out computational studies for the estimation of chemical and structural properties of a chemical library of nine ortho substituted naphthoic acids. The chemical reactivity of the selected substituted naphthoic acids was assessed from a number of physicochemical properties such as total energy, HOMO-LUMO gap, chemical hardness, binding energy, ionization potential, electron affinity, electronegativity, electrochemical potential, global softness, electrophilicity and dipole moment. The effect of the electron-donor groups on conjugation of ortho substituted naphthoic acid was investigated by correlating the calculated rotational barriers of transition state of cis and trans ortho-substituted naphthoic acids to observe change in single bond length, double bond length, bond angle, dihedral angle, and rotational frequency of carboxylic group of substituted napthoic acids. The rotational barrier correlated with the geometric, atomic, molecular, and spectroscopic parameters. Moreover, quantitative structure–activity relationship (QSAR) analyses was performed and the obtained structural properties were linked with biological activities.

Highlights

The study of naphthoic acid-based xenobiotics is necessary for understanding their transformative pathways and exploring their pharmaceutical antagonist properties [1]
The values of frontier molecular orbital energies (HOMO and LUMO), energy band gap (Egap), electron affinity (EA), ionization energy (IE), dipole moment (μ), hardness ( ƞ ), softness ( Ϭ ), electronegativity (χ), electrophilicity index (ω), charge distribution, bond angles (θ) and bond lengths (Å) of nine ortho substituted naphthoic acids were calculated as listed in Tables 1 - 3
Computational studies revealed that conformational changes are induced by substituents on naphthoic acid

Summary

Introduction

The study of naphthoic acid-based xenobiotics is necessary for understanding their transformative pathways and exploring their pharmaceutical antagonist properties [1]. Literature survey reveals that extensive research has been carried out on naphthoic acid to improve its application as an intermediate for the synthesis of pharmaceuticals, photochemicals, plant growth hormones, dyes and other useful organic compounds [2, 3]. For instance the triplet energy state of naphthoic acid functionalized with polymer can be tuned to match the energy level of a transition metal to enhance fluorescence emission of the complex formed when electron donating groups are substituted on the aryl conjugated system [4]. A report on naphthoic acid derivatives suggests that COOH group, methyl and halogen substituents are required to be in the right configuration for exerting a biological action [5].

Methods

Results

Conclusion