A novel 2,5-diaminopyrimidine-based affinity probe for Bruton's tyrosine kinase

Discovery of selective irreversible inhibitors of B-Lymphoid tyrosine kinase (BLK)

B-lymphoid tyrosine kinase (BLK), a member of the SRC family nonreceptor tyrosine kinase, is involved in the B-cell receptor (BCR) signaling pathway and B cell development and function. Dysregulation of BLK is associated with autoimmune diseases and cancer. However, there is an absence of good tool compounds for BLK, and the molecular mechanisms by which BLK mediates physiological and pathological processes are poorly understood. Herein, we present the discovery of a novel series of selective and irreversible inhibitors of BLK with nanomolar potency against BLK in biochemical and cellular assays. Compound 25 demonstrated potent antiproliferative activities against several B cell lymphoma cell lines. These compounds constitute the first series of selective inhibitors developed for BLK and could help expedite the exploration of BLK functions.

Protein degradation through covalent inhibitor-based PROTACs

Covalent inhibitor-based PROTACs were successfully developed for the degradation of target proteins in live cells to further extend the application scope of PROTACs.

Enzyme-Activated Fluorogenic Probes for Live-Cell and in Vivo Imaging

Fluorogenic probes, small-molecule sensors that unmask brilliant fluorescence upon exposure to specific stimuli, are powerful tools for chemical biology. Those probes that respond to enzymatic catalysis illuminate the complex dynamics of biological processes at a level of spatiotemporal detail and sensitivity unmatched by other techniques. Here, we review recent advances in enzyme-activated fluorogenic probes for biological imaging. We organize our survey by enzyme classification, with emphasis on fluorophore masking strategies, modes of enzymatic activation, and the breadth of current and future applications. Key challenges such as probe selectivity and spectroscopic requirements are described alongside therapeutic, diagnostic, and theranostic opportunities.