In-silico Studies, Synthesis, and Antibacterial Evaluation of Thiophene Linked Isoxazole Derivatives

In this work a series of thiophene linked isoxazole derivatives (LK1-LK8) was synthesized by cyclization of different substituted thienyl chalcones (PL1-PL8). The structures of the synthesized compounds were characterized by IR, 1H NMR and mass spectral data. These derivatives were evaluated for antibacterial activities. Compounds LK7 showed excellent antibacterial activities amongst the synthesized compounds with MIC value 6.75 µg/ml. Molecular docking of these linked isoxazole derivatives (LK1-LK8) was also performed with crystal structure of staph gyrase B 24kDa (PDB code: 5 4URM). All the isoxazole derivatives (LK1-LK8) were docked into same groove of the binding site of native co-crystallized (1R,4aS,5S,6S,8aR)-5-{[(5S)-1-(3-O-acetyl-4-O-carbamoyl-6-deoxy-2-O-methyl-alpha-L-talopyra nosy l)-4 hydroxy 2-oxo-5-(propan-2-yl)-2,5-dihydro-1H-pyrrol-3-yl]carbonyl}-6-methyl-4 1, 2, 3, 4 methylid-ene,4a,5,6,8a-octahydronaphthalen-1-yl2,6-dideoxy-3-C-[(1S)-1-{[(3,4-dichloro-5-methyl-1 H-pyrrol-2-yl) carbonyl]amino}ethyl]-beta-D-ribo-hexopyranoside) ligand for activity explanation and exhibited good ligand interaction and binding affinity were of range -2.04 to -4.34 kcal/mol.