Synthesis of some Novel Nitrogenous Heterocyclic Compounds with Expected Biological Activity as Antimicrobial and Cytotoxic Agents

Abstract

This study includes synthesis of some nitrogenous heterocyclic compounds linked to amino acid esters or heterocyclic amines that may have a potential  activity as antimicrobial and/or cytotoxic.  Quinolines are an important group of organic compounds that possess useful biological activity as antibacterial, antifungal and antitumor .8-Hydroxyquinoline (8-HQ) and numerous of its derivatives exhibit potent activities against fungi and bacteria which make them good candidates for the treatment of many parasitic and microbial infection diseases.

These pharmacological properties of quinolones  aroused our  interest in synthesizing several new compounds featuring heterocyclic rings of the quinoline derivatives linked to amino acid ester or heterocyclic amine with the aim of obtaining a pharmacologically active compounds.O-alkylation has been done on( 8-hydroxyquinoline ) to get (O-alkylated ester) derivatives which are deesterfied to get acetic acid derivatives, then coupled with amino acid that have protected carboxyl group (amino acid esters) or heterocyclic amine by using conventional solution  method for peptide synthesis as a coupling method.

The proposed analogues were successfully synthesized and the processing of the reactions confirmed by TLC ,the synthesized  analogues with the proposed structures as they were characterized and proved by  melting point, infrared spectroscopy (IR) and elemental microanalysis.

The tested analogues showed cytotoxic activity on the HEp-2 cell line (tumor of larynx) with inhibitory concentration percent of (IC %) range (32.43 % - 49.55%) and showed that the tested compounds had variable antimicrobial activities against selected bacteria and yeast when compared with selected standard drugs.

Keywords: Quinolones, 8-hydroxyquinoline , N-heterocycles biological activity.