Discovery of indoline-based derivatives as effective ROCK2 inhibitors for the potential new treatment of idiopathic pulmonary fibrosis

•A series of compounds based on indoline were designed and synthesized as novel ROCK2 inhibitors.•The systematic evaluation and screening leaded to the discovery of selective ROCK2 inhibitors.•Compound 9b showed potent ROCK2 inhibitory potency with an IC50 value of 6 nM.•Compound 9b demonstrated excellent anti-fibrotic effect in bleomycin-induced rat model in vivo.