Iniparib

• CAT Number: I002034
• CAS Number: 160003-66-7
• Molecular Formula: C₇H₅IN₂O₃
• Molecular Weight: 292.03
• Purity: ≥95%
• Target: PARP
• Solubility: DMSO ≥56mg/mL Water <1.2mg/mL Ethanol ≥35mg/mL
• Storage: 3 years -20C powder
• InChI: InChI=1S/C7H5IN2O3/c8-5-2-1-4(7(9)11)3-6(5)10(12)13/h1-3H,(H2,9,11)
• InChIKey: MDOJTZQKHMAPBK-UHFFFAOYSA-N
• SMILES: C1=CC(=C(C=C1C(=O)N)[N+](=O)[O-])I

BSI-201 (Iniparib; NSC-746045) is a PARP1 inhibitor with demonstrated effectiveness in triple-negative breast cancer (TNBC).IC50 Value:Target:PARP1in vitro: BSI-201 inhibits the growth of E-ras 20 cells, the effect of which can be augmented 4-fold when BOS is added. Recently BSI-201 shows no ability to inhibit PARP enzymatic or cellular activity, but can non-selectively modify cysteine-containing proteins in tumor cells, suggesting the mechanism of action for BSI-201 is likely not via inhibition of PARP activity. BSI-201 (100 μM) inhibits ionizing radiation-induced single-strand breaks (SSBs) repair in human lymphoid cell lines based on large endogenous Epstein–Barr virus (EBV) circular episomes assay, resulting in 55% repair by 2 hours, which can be reversed surprisingly by knockdown of PARP1, indicating that the mechanism of inhibition does not involve trapping PARP at SSBs. BSI-201 is not able to selectively kill homologous recombination (HR)-deficient cells between BRCA2-deficient PEO1 and BRCA2-revertant PEO4, or ATM-deficient GM16666 and ATM-restored GM16667 fibroblasts. BSI-201 is cytotoxic to a variety of cell lines at concentrations above 40 μM reflecting a mechanism independent of PARP.

Reference

1:Cancer Biol Ther. 2009 Jan;8(1):2-3. BiPar Sciences presents interim phase 2 results for PARP inhibitor BSI-201 at San Antonio Breast Cancer Symposium. PMID: 19455741