YCH1899 is an orally active PARP inhibitor, with an IC 50 < 0.001 nM for PARP1/2. YCH1899 exhibits distinct antiproliferation activity against Olaparib -resistant and Talazoparib -resistant Capan-1 cells (Capan-1/OP and Capan-1/TP cells) , with IC 50 values of 0.89 and 1.13 nM, respectively. YCH1899 has acceptable pharmacokinetic properties in rats.