– ZNL0325 is a covalent probe based on pyrazolo[1,2-a]pyrimidine that demonstrates an alternative binding mode for kinases, where the C3 position is reversed facing the ribose-binding pocket. ZNL0325 and its analogs feature an acrylamide side chain at the C3 position, capable of forming covalent bonds with various kinases possessing cysteine at the αD-1 position, including BTK, EGFR, BLK, and JAK3.