ACBI3 (compound 7) is a PROTAC targeting KRAS . ACBI3 is composed of PROTAC target protein ligand pan-KRAS degrader 1 (red part), E3 ligase ligand E3 ligase Ligand 43 (blue part) and PROTAC Linker 1-Bromo-4-(ethynyloxy)butane (black part), among which the conjugate of E3 ubiquitin ligase ligand + Linker is E3 Ligase Ligand-linker Conjugate 143. ACBI3 achieves in vivo degradation of oncogenic KRAS, resulting in durable pathway modulation and tumor regressions in KRAS mutant xenograft mouse models.