College of Natural and Computational Sciences
Permanent URI for this communityhttps://etd.hu.edu.et/handle/123456789/89
Browse
Item DESIGN AND SYNTHESIS OF SOME NOVEL HYBRID MOLECULES CONTAINING INDOLE AND OXADIAZOLE RING FOR EVALUATION OF ANTIBACTERIAL AND ANTIOXIDANT ACTIVITIES(Hawassa University, 2024-06) AMANUEL ABRIHAM BUDEIndole-containing oxadiazole compounds have emerged as a versatile class of nitrogen containing heterocyclic compounds with a wide range of biological activities. These compounds and their derivatives exhibit a diverse array of properties such as antiviral, anticancer, anti-HIV, antioxidant, antimicrobial, antidiabetic, and antimalarial activities. The aim of the study was to design and synthesize some novel hybrid molecules containing an indole and oxadiazole rings, followed by partial characterization of the synthesized compounds using UV-vis and FT-IR spectroscopic techniques, and assessment of their antibacterial and antioxidant activities. The synthetic methodology was initiated by esterification of 2-(1H-indol-3-yl) acetic acid (105aʹ) and 4-(1H-indol-3-yl) butanoic acid (105bʹ) using a catalytic amount of sulfuric acid and excess methanol. This process resulted in the formation of methyl 2-(1H-indol-3-yl)acetate (106aʹ) and methyl 4-(1H-indole-3-yl)butanoate (106bʹ) respectively. These esters were further converted to 2-(1H-indol-3-yl)acetohydrazide (107aʹ) and 4-(1H-indole-3-yl)butaneydrazide (107bʹ) respectively. Finally, the compounds (107aʹ) and (107bʹ) underwent a reaction with substituted carboxylic acids in the presence of POCl3 to produce the desired targeted compounds: 110aʹ, 111aʹ, 110bʹ, and 111bʹ. The synthesized compound yields were as follows: 110aʹ (62%), 111aʹ (55%), 110bʹ (57%), and 111bʹ (53%). The chemical structures of these synthesized compounds were partially characterized by using spectroscopic techniques like UV-Vis and FT-IR. The synthesized compounds were evaluated for their in vitro antibacterial activity test against four bacterial strains: E. coli, P. aeruginosa, S. pyogenes and S. aureus by the disk diffusion method. Among synthesized compounds, compound 111bʹ showed potent inhibitory activity against Gram-negative, E. coli with 11.57 ± 0.15 mm zone of inhibition compared to the standard drug tetracycline (13 ± 0.5 mm) at 150 mg/mL. The RSA of synthesized compounds were assessed through DPPH radical assay, revealing that compounds 111aʹ and 110aʹ demonstrated higher %RSA (91.83% and 89.9%, respectively) with IC50 values of 4.95 and 5.03, respectively, compared to the standard ascorbic acid of %RSA (87.5%) with an IC50 of 31.44 and than other synthesized compounds. Hence, the studies have indicated that all the synthesized compounds could be considered as potential candidates for further investigation in antibacterial and antioxidant research.