Synthesis, Computational Study of β-lactam Derivatives Bearing Quinazoline Schiff Bases as Anthelmintics

Abstract

Infections caused by parasites continue to pose a risk to both human and animal health. The most popular drug classes for treating these infections include thiabendazole, imidazothiazoles, levamisole, and avermectins (obtained from the fermentation products of Streptomyces avermitilis). The majority of bacteria that we come across in any form of infection are successfully combatted by β- lactam medicines. Similar to the majority of treatments, problems with treatment resistance to these drugs have evolved over time, necessitating the development of new anthelmintic medications. This study aims to investigate a series of quinazoline-bearing β-lactam rings as potent anthelmintic agents. The new series of quinazoline bearing β-lactam was synthesized via reaction of 5-bromo anthranilic acid with acetic anhydride to produce 6-bromo-2-methyl-4H-benzo (1,3) oxazin-4-one which was then converted into 3-amino-6-bromo-2-methylquinazolin-4(3H)-one by the reaction of hydrazine hydrate in the presence of anhydrous pyridine. The resultant intermediate then goes through a Schiff reaction with various aromatic aldehydes, followed by reflux with triethylamine and chloroacetyl chloride. Structural assignments of these compounds have been made by elemental analysis, FTIR,1HNMR and Mass spectral data and the purity of the compounds was determined by TLC. Molecular docking studies showed the effective binding of synthesized derivatives with tubulin in comparison to the orientation of standard drugs. The anthelmintic activities of all the synthesized compounds were evaluated separately for their possible using common Indian earthworm Pheritima posthuma. A total of ten derivatives of quinazoline bearing β-lactam ring were designed, synthesized and evaluated against the Indian earthworm Pheritima posthuma. Out of ten derivatives, SQD2 and SQD6, showed promising anthelmintic activity when compared with standard drugs albendazole and piperazine citrate.