Novel Pyrimidines as Multitarget Protein Tyrosine Kinase Inhibitors for the Treatment of Idiopathic Pulmonary Fibrosis (IPF).

A new class of pyrimidine derivatives were identified as potent protein tyrosine kinase (PTK) inhibitors for the treatment of idiopathic pulmonary fibrosis (IPF). Most of these small-molecule inhibitors displayed strong enzymatic activity against BTK and JAK3 kinases at concentrations lower than 10 nM. The representative compound N-(3-((5-chloro-2-(4-((1-morpholino)acetylamino)phenylamino)-4-pyrimidinyl)amino)phenyl)acrylamide (6 a) also exhibited high inhibitory potency toward both BTK and JAK kinase families, as well as ErbB4, at a concentration of 10 nM, achieving rates of inhibition higher than 57 %. Additionally, in vivo biological evaluations showed that 6 a can remarkably decrease the severity of IPF disease. All these investigations suggested that the multi-PTK inhibitor 6 a may serve as a promising agent for the treatment of IPF.