Related Experiment Video
Updated: Jul 28, 2025

Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
Synthesis of antioxidant and antimicrobial bioactive compounds based on the quinoline-hydrazone and benzimidazole
Antonius Herry Cahyana1, Devin Halim1, Laely Amaliyah1
1Department of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Indonesia, Depok, West Java, Indonesia.
Abstract:
Quinoline and its derivatives are known to have various biological activities such as antibacterial and antioxidant. Therefore, this study aims to synthesize quinoline moiety from isatin and ethyl acetoacetate by Pfitzinger reaction under acidic conditions. The benzimidazole derivative was synthesized from quinoline and o-phenylenediamine by a solvent-less reaction, while the hydrazone derivative was formed by the reaction with hydrazine hydrate and aromatic aldehyde. In addition, 4-hydroxybenzaldehyde was used as an aromatic aldehyde. The four compounds formed were characterized by thin-layer chromatography (TLC), melting point measurement, Fourier-transform infrared, liquid chromatography-mass spectrometry, and ultraviolet-visible spectrophotometry. They were also evaluated for their antioxidant and antimicrobial activities using the 2,2-diphenyl-1-picrylhydrazyl assay and the disc diffusion method, respectively. All compounds showed weak antioxidant activity compared to ascorbic acid; the quinoline-hydrazone derivative showed the best antioxidant activity with IC50 = 843.52 ppm, while the IC50 value for quinoline-benzimidazole was 4784.66 ppm. All synthesized compounds have not been confirmed to be effective against Staphylococcus aureus and Escherichia coli bacteria in a concentration range of 75-1000 ppm. The bioactive compounds based on the quinoline-hydrazone and benzimidazole structures have been successfully synthesized and tested for their activity as antioxidant and antimicrobial agents.
More Related Videos
05:59Author Spotlight: Advancing Antimicrobial Resistance Research with Innovative Approaches and Synthetic Compounds
Published on: September 27, 2024
06:34Synthesis of Antiviral Tetrahydrocarbazole Derivatives by Photochemical and Acid-catalyzed C-H Functionalization via Intermediate Peroxides CHIPS
Published on: June 20, 2014
Related Concept Videos
Oxidation of Phenols to Quinones
o-hydroxy phenols are oxidized to o-quinones and p-hydroxy phenols to p-quinones. Such redox reactions involve the transfer of two electrons and two protons. The reversible redox...
Aryldiazonium Salts to Azo Dyes: Diazo Coupling
Structure of Benzene: Kekulé Model
He proposed that benzene has a cyclic structure of six carbon atoms attached to one hydrogen atom each, with three alternating pi bonds.
Electrophilic Aromatic Substitution: Nitration of Benzene
Electrophilic Aromatic Substitution: Fluorination and Iodination of Benzene
Electrophilic Aromatic Substitution: Sulfonation of Benzene