YCH3971 

YCH3971 is a PARP1 inhibitor with a PARP1 IC₅₀ of 7.52 nM and a PARP1 EC₅₀ of 67.75 nM. YCH3971 inhibits the proliferation of BRCA-deficient tumor cells. YCH3971 induces DNA damage, G2/M phase arrest, and caspase-mediated Apoptosis in triple-negative breast cancer cells. YCH3971 can be used for the research of BRCA-deficient tumors^[1].

YCH3971 (0.01-10000 nM, 7 days) potently inhibits the proliferation of BRCA1-deficient MDA-MB-436 cells, with an IC₅₀ of 2.10 nM^[1].
YCH3971 (0.01-10000 nM, 7 days) inhibits the proliferation of BRCA2-deficient V-C8 cells with an IC₅₀ of 69.61 nM, while it exhibits only extremely weak activity against BRCA2-proficient V79 cells^[1].
YCH3971 (0.01-10000 nM, 7 days) inhibits the proliferation of BRCA1-mutant UWB1.289 ovarian cancer cells with an IC₅₀ of 112.86 nM, whereas it shows almost no activity against UWB1.289 + BRCA1 cells with restored BRCA1 expression^[1].
YCH3971 (0.01-1 μM; 48 h) induces dose-dependent DNA damage in MDA-MB-436 cells^[1].
YCH3971 (0.01-1 μM; 3 days) induces dose-dependent G2/M phase arrest in MDA-MB-436 cells^[1].
YCH3971 (0.01-1 μM; 4 days) induces dose-dependent caspase-mediated apoptosis in MDA-MB-436 cells^[1].

MedChemExpress (MCE) has not independently confirmed the accuracy of these methods. They are for reference only.

387.48

C₂₃H₂₅N₅O

CC1=C(N2CCN(CC3=CN4C(C=C(C5CC5)C(N4)=O)=C3)CC2)C=CC(C#N)=C1

Room temperature in continental US; may vary elsewhere.

Please store the product under the recommended conditions in the Certificate of Analysis.

• [1]. Qiaolin He, et al. Design, synthesis and biological evaluation of novel
  pyrrolo[1,2-b]pyridazin-2(1H)-ones as selective PARP1 inhibitors for cancer therapy. European Journal of Medicinal Chemistry
  Volume 307, 5 April 2026, 118650.