Design, Synthesis And Characterization Of Novel Pirtobrutinib Analogues As Anticancer BTK Inhibitors

Abstract

Bruton tyrosine kinase (BTK) is a validated therapeutic target in B-cell malignancies, and pirtobrutinib is an important non-covalent BTK inhibitor developed to retain activity in settings where resistance to covalent BTK inhibitors may occur. The present manuscript draft describes a rational medicinal-chemistry framework for the design, synthesis and preliminary biological evaluation of novel pirtobrutinib analogues as anticancer BTK inhibitors. A focused analogue library was designed around the pirtobrutinib pharmacophore by retaining the pyrazole-carboxamide hydrogen-bonding region and varying selected aryl, amide, lipophilic and solubilizing substituent zones. Candidate analogues were prioritized using docking-based BTK interaction analysis, physicochemical screening and drug-likeness filters. The proposed synthetic strategy involved modular amide coupling and late-stage substituent diversification, followed by purification and confirmation of chemical identity using FTIR, 1H NMR, 13C NMR, mass spectrometry and elemental analysis. Representative biological assessment included enzyme-based BTK inhibition, cell-viability assays in BTK-dependent B-cell cancer models, selectivity assessment against non-malignant cells, apoptosis markers and preliminary in silico ADMET profiling. The representative dataset suggests that selected analogues with strengthened hinge-region interaction, balanced lipophilicity and improved solubility may demonstrate enhanced BTK inhibition and anticancer response compared with the parent scaffold. The work provides a structured research-paper format for developing pirtobrutinib-inspired analogues and supports further experimental validation through kinase panel screening, resistant-cell models and pharmacokinetic evaluation.