PHARMACOPHORE-GUIDED VIRTUAL SCREENING FOR DRUG REPURPOSING AND BENZOFURAN LEAD OPTIMIZATION TOWARD SELECTIVE ALLOSTERIC MODULATION OF PROTEIN TYROSINE PHOSPHATASE 1B (PTP1B)

Abstract

Protein Tyrosine Phosphatase 1B (PTP1B) is a key negative regulator of insulin and leptin signaling and plays a central role in the development of insulin resistance and associated cardiometabolic disorders. Although PTP1B is a validated therapeutic target for type 2 diabetes, the clinical translation of active-site inhibitors has been hindered by poor selectivity, off-target effects, and limited bioavailability due to the high conservation of the catalytic pocket among protein tyrosine phosphatases. Allosteric inhibition has therefore emerged as a promising strategy for selectively modulating PTP1B activity. In this study, an integrated in silico and experimental approach was employed to identify and characterize selective allosteric inhibitors of PTP1B. A structure-based pharmacophore model targeting the allosteric site was developed and validated, and subsequently used to screen an FDA-approved drug library. In parallel, a series of in-house benzofuran derivatives was evaluated based on their structural suitability for allosteric binding. Top-ranked compounds were subjected to molecular docking at both the allosteric and catalytic sites of PTP1B, and the allosteric site of TC-PTP, followed by molecular dynamics simulations and MM/GBSA binding free energy calculations to assess binding stability, selectivity, and conformational effects on the WPD loop. The most promising candidates were experimentally evaluated using a recombinant PTP1B enzymatic inhibition assay. Several compounds demonstrated notable inhibitory activity and favorable selectivity profiles, supporting the computational predictions. Collectively, these findings highlight benzofuran-based scaffolds and repurposed FDA-approved drugs as promising leads for selective allosteric inhibition of PTP1B. This study provides a rational framework for the discovery of safer and more effective PTP1B-targeted therapeutics for metabolic disorders.