Synthesis of novel N-(2,3-dihydro-1,4-benzodioxin-6-yl)-2-{[5-(un/substituted-phenyl)-1,3,4 -oxadiazol-2-yl]sulfanyl}acetamides as potent antibacterial agents

The synthetic methodology was initiated by reacting 1,4-benzodioxane-6-amine (1) with 2-bromoacetyl bromide (2) in aqueous alkaline media under dynamic pH control to get compound 2,3-dihydro-1,4-benzodioxin-6-yl-2bromoacetamide (3). In the subsequent reactions, a variety of un/substituted-benzoic acids (4a-k), through a succession of three steps, was converted into respective oxadiazole nucleophiles, 7a-k. Finally, the targeted molecules, 8a-k, were obtained by reacting 7a-k with electrophile 3 in an aprotic polar solvent. These compounds were corroborated by spectral characterization like IR, EI-MS, 1H-NMR, and CHN analysis data. These molecules were screened for their antibacterial potential and most of them exhibited a potent activity. Moreover, their cytotoxicity was profiled through hemolytic activity and it was observed that majority of them was very modest in toxicity.