Synthesis, Characterization And Biological Evaluation Of Novel Benzothiazole–Pyrazole Derivatives

A focused series of six substituted benzothiazole–pyrazole derivatives (VI-a–VI-f) was prepared from 2-amino-7-chloro-6-fluorobenzothiazole through sequential hydrazine conversion, hydrazone formation, cyclization/formylation and incorporation of a piperidinyl substituent. The synthesized compounds were examined by physicochemical characterization and spectroscopic techniques, including FT-IR and ¹H-NMR, together with elemental-composition data reported in the source manuscript. Their preliminary biological profile was assessed using in-vitro albumin-denaturation and in-vivo carrageenan-induced paw-edema models, together with cup-plate antibacterial and antifungal assays. The derivatives displayed measurable activity across the tested models. In the albumin-denaturation assay, VI-b produced the highest inhibition among the synthesized compounds (71%), while VI-d showed 51.43%. In the animal model, VI-a, VI-d and VI-f produced approximately 51% inhibition of paw edema. Antibacterial screening demonstrated concentration-dependent zones of inhibition against selected Gram-positive and Gram-negative organisms, with VI-b showing a particularly prominent response against Staphylococcus aureus at 100 µg/mL. Antifungal screening against Candida albicans and Aspergillus flavus also showed activity, although the standard remained superior. Overall, the data support further optimization of this benzothiazole–pyrazole scaffold as a preliminary pharmacological lead, while additional mechanistic, toxicological and reproducibility studies are required.