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Facile Preparation of 4-Substituted Quinazoline Derivatives
Published on: February 15, 2016
Synthesis and structure-activity relationships of new antimicrobial active multisubstituted benzazole derivatives
Ilkay Yildiz-Oren1, Ismail Yalcin, Esin Aki-Sener
1Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Ankara University, Tandogan, 06100 Ankara, Turkey.
Abstract:
A series of multisubstituted benzoxazoles, benzimidazoles, and benzothiazoles (5-7) as non-nucleoside fused isosteric heterocyclic compounds was synthesized and tested for their antibacterial activities against various Gram-positive and Gram-negative bacteria and antifungal activity against the fungus Candida albicans. Microbiological results indicated that the synthesized compounds possessed a broad spectrum of activity against the tested microorganisms at MIC values between 100 and 3.12 microg/ml. Structure-activity relationships (SAR) studies revealed that benzothiazole ring system enhanced the antimicrobial activity against Staphylococcus aureus. In these sets of non-nucleoside fused heterocyclic compounds electron withdrawing groups at position 5 of the benzazoles increased the activity against C. albicans.
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