– YJ1206 is a highly potent and selective CDK12/13 PROTAC degrader (IC50 =12.55 nM) with the advantages of oral administration and low toxicity, which triggers gene-length-dependent transcription elongation defects, leading to DNA damage and cell-cycle arrest, and inhibits the proliferation of a subpopulation of prostate cancer cells. YJ1206 can synergize with AKT pathway inhibitors to effectively inhibit prostate cancer.