Norastemizole

Norastemizole is a histamine H1 receptor antagonist (IC50 = 4.1 nM) and an active metabolite of the histamine H1 receptor antagonist and ether-a-go-go (ERG) channel blocker astemizole (Cay-16967). It is formed from astemizole by the cytochrome P450 (CYP) isoform 3A4 (CYP3A4). Norastemizole also inhibits currents in a whole-cell patch-clamp assay using HEK293 cells expressing human-ether-a-go-go (hERG), also known as Kv11.1 (IC50 = 27.7 nM). It prevents IL-1beta-induced increases in the levels of intracellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in human umbilical vein endothelial cells (HUVECs) when used at a concentration of 100 µM. Norastemizole (1 mg/kg) inhibits passive cutaneous anaphylaxis induced by ovalbumin (OVA) or the biogenic amine histamine (Cay-33828), but not by bradykinin, in guinea pigs. It inhibits eosinophil infiltration into the lungs of mice in a mouse model of OVA-induced asthma when administered at a dose of 1 mg/kg.Formal Name: 1-[(4-fluorophenyl)methyl]-N-4-piperidinyl-1H-benzimidazol-2-amine. CAS Number: 75970-99-9. Synonyms: Tecastemizole. Molecular Formula: C19H21FN4. Formula Weight: 324.4. Purity: >98%. Formulation: (Request formulation change), A solid. Solubility: DMSO: Sparingly soluble: 1-10 mg/ml, Ethanol: Slightly soluble: 0.1-1 mg/ml. SMILES: FC(C=C1)=CC=C1CN2C3=C(N=C2NC4CCNCC4)C=CC=C3. InChi Code: InChI=1S/C19H21FN4/c20-15-7-5-14(6-8-15)13-24-18-4-2-1-3-17(18)23-19(24)22-16-9-11-21-12-10-16/h1-8,16,21H,9-13H2,(H,22,23). InChi Key: SFOVDSLXFUGAIV-UHFFFAOYSA-N.