Synthesis and Functionalization of Novel Quinazoline Scaffolds as Antibacterial Agents
A new series of Quinazoline derivatives have been designed and synthesized using palladium-catalyzed reactions. The antibacterial activities of the synthesized compounds were screened against four pathogenic bacteria. Compounds 18b and 9 showed higher sensitivity to S. aureus (gram-positive) with an MIC ≤ 0.25-0.5 μg/ml, respectively. Meanwhile, compounds 13a and 13b were more effective against gramnegative bacteria, with an MIC<0.25 μg/ml against Escherichia coli, and high activities against Pseudomonas aeruginosa, with MIC values of 0.5 and 1.0 μg/ml, respectively. The broadest antibacterial activities were observed with the quinazolines 26a-c, which had MIC value ranging from<0.25-2 μg/ml. A β-cyclodextrin (β-Cyd) inclusion complex containing quinazolines as a guest was prepared using the kneading method. The product was characterized by FTIR and 1H NMR spectrometry, which proved the formation of the inclusion compound between the host and guest at a molar ratio of 2:1. Based on the results from the present study, some quinazolines could be used as a template for the future development of more potent therapeutic agents through modification or derivatization.
Shaikha S-A-Neyadi, Alaa A Salem, Akela Ghazawi, Tibor Pal and Ibrahim M Abdou*