SCXRD, DFT and molecular docking based structural analyses towards novel 3-piperazin-1-yl-benzo[d]isothiazole and 3-piperidin-4-yl-benzo[d]isoxazoles appended to quinoline as pharmacological agents

•Novel quinoline containing 3-piperazin-1-yl-benzo[d]isothiazole and 3-piperidin-4-yl-benzo[d]isoxazoles were synthesized.•The single crystal XRD, DFT studies and in silico pharmacokinetic and toxicity parameters were done.•In vitro antimicrobial activity was analysed and correlated with energy difference in Frontier Molecular Orbitals.•Antimicrobial activity observed from in vitro assays and DFT studies were validated by Docking studies. Novel quinoline containing 3-piperazin-1-yl-benzo[d]isothiazole 4a and 4b and 3-piperidin-4-yl-benzo[d]isoxazole 5c were synthesized and characterized by spectral, single crystal XRD and DFT studies. Hirshfeld surface, electrostatic potential maps were obtained respectively from SCXRD and DFT studies. These compounds were analysed for in vitro antimicrobial activity and correlated with energy difference (ΔE) between HOMO and LUMO energy levels obtained from DFT and correlated with ΔE of standard drug to explain the activity. Further the antimicrobial activity was corroborated by docking against various target enzymes. The present work provided some hints for developing novel antimicrobial quinoline derivatives. [Display omitted]