Rising cases of antibiotic-resistant bacteria is a public health concern. Many approved antibiotics target penicillin-binding proteins example peptidoglycan transpeptidase (PTPase). Due to wide pharmacological activity of phenothiazines, new styryl, aryl, alkynyl, and thiophenyl benzo[a]phenothiazines were synthesized and their inhibitory potency against PTPasein silico and Gram-po...