Green Synthesis of Quinoline-Based Ionic Liquid

Summary

In the present work, we elucidate the green synthesis of quinoline-based Ionic Liquid (IL), namely, 1-Hexadecylquinolin-1-ium bromide {[C₁₆quin]Br} by mixing quinoline with an excess of 1-Bromohexadecane, along with its detailed characterization using Nuclear Magnetic Resonance and Infrared spectroscopic measurements.

Abstract

The ever-growing menace of Antimicrobial Resistance (AMR) jeopardizes the potency of the prevailing antibiotics against the relentlessly sprouting infections spawned by bacteria, viruses, parasites as well as fungi, posing a great threat to human health and well-being. In this regard, several novel molecules have proved their mettle, with Ionic Liquids (ILs) being one of the most eco-friendly, non-volatile, and thermally stable alternatives to the existing antimicrobials, possessing high solvating potential as well as low vapor pressure. Moreover, the utilization of these entities in both stabilizing as well as destabilizing protein structures and enhancing enzymatic activity has further raised their potential in the biomedical industry. With this in view, we present the green synthesis and characterization of quinoline-based IL, owing to its immense antimicrobial potency, with low cytotoxicity and great artificial chaperone activity. Here, maneuvering the one-pot synthesis approach in solvent-free, greener reaction conditions not only ameliorated the reaction efficiency but also augmented the chemical yield. The purity of the synthesized IL was corroborated using 1H Nuclear Magnetic Resonance (NMR), 13C NMR, and Infrared (IR) spectroscopy. The biological potential of the synthesized compound is further validated by analyzing its Absorption, Distribution, Metabolism, Excretion, and Toxicity (ADMET) properties and authenticated using disc diffusion assay.

Introduction

The monumental growth in the world population accounts for a tremendous increment in the consumption of a vast array of commodities over the past few years, including food, medicaments, as well as other crucial products for the sustenance of mortal organisms. This has invigorated the quest for novel chemical compounds with exceptionally specialized, ecologically sound, and beneficial properties worldwide. Ionic Liquids (ILs) have proved to be felicitous in this regard. The implication of these compounds in the scientific domain has bolstered new ventures in research in contemporary chemical technologies¹. In contrast to the conventional approac....

Protocol

NOTE: 1-Hexadecylquinolin-1-ium bromide{[C₁₆quin]Br} was synthesized as described previously by Sharma et al.¹³.

1. Preparation and sterilization of glass apparatus

NOTE: This should be done at least 1 day prior to setting up the reaction for the synthesis of the desired compound.

1. Wash a 24/29, 250 mL, two-neck round bottom flask (RB) thoroughly, along with other glass apparatus such as measuring cylin.......

Discussion

Lately, ILs have divulged various promising implementations in the field of biochemical sciences including protein refolding/ chaperone activity, drug delivery vehicles, and/or catalysts in several organic reactions. Their intriguing physicochemical properties, such as tunability, biocompatibility, solubility, sustainability, stability, etc., have made them potential candidates for the development of novel therapeutic agents²⁰. The proposed research visualizes AMR as a matter of grave concern and .......

Materials

Name	Company	Catalog Number	Comments
1-bromohexadecane	Merck	CAS no.112-82-3	95% pure (as determined by HPLC analysis)
Ethyl acetate	Merck	CAS no. 205-500-4	95% pure (as determined by HPLC analysis)
Nuclear Magnetic Resonance (NMR) spectrometer	Jeol, Model: JNM-ECZ 400S	Nil	Nil
Quinoline	Merck	CAS no.91-22-5	95% pure (as determined by HPLC analysis)
Toluene	Merck	CAS no. 108-88-3	95% pure (as determined by HPLC analysis)