Urapidil (hydrochloride)

Urapidil is an antagonist of alpha1-adrenergic receptors (alpha1-ARs) and a partial agonist of the serotonin (5-HT) receptor subtype 5-HT1A. It selectively binds to alpha1- over alpha2-ARs (IC50s = 0.74 and 42 µM, respectively) and to 5-HT1A over 5-HT1B and 5-HT2 receptors (IC50s = 0.4, 20.4, and >10 µM, respectively) in rat cortex. Urapidil inhibits cAMP accumulation induced by forskolin in calf hippocampus as a functional model for 5-HT1A receptors (EC50 = 390 nM). It is also a beta1-AR antagonist that inhibits the positive chronotropic response induced by isoproterenol (Cay-15592) in isolated rat atria (pA2 = 6.05). Urapidil (1 µmol/kg, i.v.) lowers mean arterial pressure (MAP) in anesthetized cats, an effect that is reduced by central administration of the 5-HT1A receptor antagonist spiroxatrine.Formal Name: 6-[[3-[4-(2-methoxyphenyl)-1-piperazinyl]propyl]amino]-1,3-dimethyl-2,4(1H,3H)-pyrimidinedione monohydrochloride. CAS Number: 64887-14-5. Molecular Formula: C20H29N5O3 . HCl. Formula Weight: 423.9. Purity: >98%. Formulation: (Request formulation change), A solid. Solubility: DMSO: 3mg/mL, PBS (pH 7.2): 10mg/mL. lambdamax: 267 nm. SMILES: COC1=CC=CC=C1N2CCN(CCCNC3=CC(N(C)C(N3C)=O)=O)CC2.Cl. InChi Code: InChI=1S/C20H29N5O3.ClH/c1-22-18(15-19(26)23(2)20(22)27)21-9-6-10-24-11-13-25(14-12-24)16-7-4-5-8-17(16)28-3,/h4-5,7-8,15,21H,6,9-14H2,1-3H3,1H. InChi Key: KTMLZVUAXJERAT-UHFFFAOYSA-N.