Design, synthesis, characterization, and anxiolytic evaluation of benzothiazole–piperazine derivatives through integrated in silico and in vivo approaches

Anxiety disorders are among the most prevalent neuropsychiatric conditions worldwide, and currently available treatments such as benzodiazepines and selective serotonin reuptake inhibitors (SSRIs) are associated with limitations including sedation, dependence, and delayed onset of action. In this study, a series of benzothiazole-based piperazine derivatives were designed, synthesized, and evaluated as potential anxiolytic agents using integrated in silico and in vivo approaches. Initially, nineteen compounds were screened for drug-likeness, ADME, and toxicity profiles using Swiss ADME and ProTox-II, followed by molecular docking against the α1β3 GABA-A receptor (PDB ID: 7PBD) to predict binding affinity and interaction patterns. The selected compounds were synthesized and characterized using FTIR, 1H NMR, 13C NMR, and LC-MS techniques. Acute toxicity evaluation further demonstrated comparatively improved safety profiles of the lead compounds at lower dose levels. The anxiolytic activity was evaluated in Wistar rats using elevated plus maze, light–dark box, and hole-board models, along with biochemical estimation of neurotransmitters. Among the tested compounds, H-9, H-14, and H-18 exhibited strong binding affinity (≤ −9.0 kcal/mol) and significant anxiolytic effects comparable to diazepam, accompanied by normalization of GABA, serotonin, and dopamine levels. The findings highlight benzothiazole–piperazine hybrid derivatives, particularly H-9, H-14, and H-18, as promising multitarget anxiolytic candidates with favorable preliminary safety profiles and demonstrate the effectiveness of integrating computational and experimental approaches for CNS drug discovery.