KRAS inhibitor-14 (compound 3-22) is a potent KRAS G12C inhibitor with an IC 50 of 0.249 µM. KRAS inhibitor-14 shows p-ERK inhibition activities with IC 50 s of 1.12, >33.3 µM in MIA PaCA-2, A549 cells, respectively. KRAS inhibitor-14 has the potential for the research of pancreatic, colorectal, and lung cancers.