DRB

DRB is a nucleoside analog that inhibits several carboxyl-terminal domain (CTD) kinases including casein kinase II (IC50 range of 4-10 µM), Cdk7 (IC50 = ~20 µM), Cdk8 (IC50 = ~20 µM), and Cdk9 (IC50 = 3 µM). Through inhibition of certain CTD kinases, DRB inhibits an elongation step during RNA polymerase II transcription, which can trigger p53-dependent apoptosis of human colon adenocarcinoma cells without inducing genotoxic stress to healthy cells. DRB can also inhibit HIV transcription (IC50 = ~4 µM) by targeting elongation enhanced by the HIV-encoded transactivator Tat.Formal Name: 5,6-dichloro-1-beta-D-ribofuranosyl-1H-benzimidazole. CAS Number: 53-85-0. Synonyms: Benzimidazole, NSC 401575. Molecular Formula: C12H12Cl2N2O4. Formula Weight: 319.1. Purity: >98%. Formulation: (Request formulation change), A crystalline solid. Solubility: DMF: 10 mg/ml, DMF:PBS (pH 7.2) (1:2): 0.3 mg/ml, DMSO: 10 mg/ml, Ethanol: 0.5 mg/ml. lambdamax: 214 nm. SMILES: O[C@@H]1[C@H](O)[C@@H](CO)O[C@H]1N2C=NC3=C2C=C(Cl)C(Cl)=C3. InChi Code: InChI=1S/C12H12Cl2N2O4/c13-5-1-7-8(2-6(5)14)16(4-15-7)12-11(19)10(18)9(3-17)20-12/h1-2,4,9-12,17-19H,3H2/t9-,10-,11-,12-/m1/s1. InChi Key: XHSQDZXAVJRBMX-DDHJBXDOSA-N.