Israpafant

Israpafant
Legal status
Legal status
Identifiers
  • (6R)-4-(2-Chlorophenyl)-2-[2-(4-isobutylphenyl)ethyl]-6,9-dimethyl-6H-thieno[3,2-f][1,2,4]triazolo[4,3-a][1,4]diazepine
CAS Number
PubChem CID
ChemSpider
UNII
CompTox Dashboard (EPA)
Chemical and physical data
FormulaC28H29ClN4S
Molar mass489.08 g·mol−1
3D model (JSmol)
  • C[C@@H]1C2=NN=C(N2C3=C(C=C(S3)CCC4=CC=C(C=C4)CC(C)C)C(=N1)C5=CC=CC=C5Cl)C
  • InChI=1S/C28H29ClN4S/c1-17(2)15-21-11-9-20(10-12-21)13-14-22-16-24-26(23-7-5-6-8-25(23)29)30-18(3)27-32-31-19(4)33(27)28(24)34-22/h5-12,16-18H,13-15H2,1-4H3/t18-/m1/s1
  • Key:RMSWMRJVUJSDGN-GOSISDBHSA-N

Israpafant (Y-24180) is a drug which acts as a selective antagonist for the platelet-activating factor receptor,[1] and was originally developed for the treatment of asthma.[2] Its chemical structure is a thienotriazolodiazepine, closely related to the sedative benzodiazepine derivative etizolam. However israpafant binds far more tightly to the platelet-activating factor receptor, with an IC50 of 0.84nM for inhibiting PAF-induced human platelet aggregation (compared to etizolam's IC50 of 998nM at this target), while it binds only weakly to benzodiazepine receptors, with a Ki of 3680nM.[3] Israpafant has been found to inhibit the activation of eosinophil cells,[4][5][6] and consequently delays the development of immune responses. It has also been shown to have anti-nephrotoxic properties,[7] and to mobilize calcium transport.[8]

  1. ^ Hirota N, Yasuda D, Hashidate T, Yamamoto T, Yamaguchi S, Nagamune T, et al. (February 2010). "Amino acid residues critical for endoplasmic reticulum export and trafficking of platelet-activating factor receptor". The Journal of Biological Chemistry. 285 (8): 5931–40. doi:10.1074/jbc.M109.066282. PMC 2820818. PMID 20007715.
  2. ^ Hozawa S, Haruta Y, Ishioka S, Yamakido M (October 1995). "Effects of a PAF antagonist, Y-24180, on bronchial hyperresponsiveness in patients with asthma". American Journal of Respiratory and Critical Care Medicine. 152 (4 Pt 1): 1198–202. doi:10.1164/ajrccm.152.4.7551370. PMID 7551370.
  3. ^ Takehara S, Mikashima H, Muramoto Y, Terasawa M, Setoguchi M, Tahara T (December 1990). "Pharmacological actions of Y-24180, a new specific antagonist of platelet activating factor (PAF): II. Interactions with PAF and benzodiazepine receptors". Prostaglandins. 40 (6): 571–83. doi:10.1016/0090-6980(90)90002-D. PMID 1965554.
  4. ^ Komatsu H, Amano M, Yamaguchi S, Sugahara K (1999). "Inhibition of activation of human peripheral blood eosinophils by Y-24180, an antagonist to platelet-activating factor receptor". Life Sciences. 65 (13): PL171-6. doi:10.1016/s0024-3205(99)00385-9. PMID 10503965.
  5. ^ Mizuki M, Komatsu H, Akiyama Y, Iwane S, Tsuda T (1999). "Inhibition of eosinophil activation in bronchoalveolar lavage fluid from atopic asthmatics by Y-24180, an antagonist to platelet-activating factor". Life Sciences. 65 (20): 2031–9. doi:10.1016/s0024-3205(99)00470-1. PMID 10579457.
  6. ^ Satoh T, Tahara E, Yamada T, Watanabe C, Itoh T, Terasawa K, et al. (February 2000). "Differential effect of antiallergic drugs on IgE-mediated cutaneous reaction in passively sensitized mice". Pharmacology. 60 (2): 97–104. doi:10.1159/000028353. PMID 10657759. S2CID 6264992.
  7. ^ Kawaguchi A, Sugimoto K, Fujimura A (January 2001). "Preventive effect of platelet-activating factor antagonist, Y-24180, against cyclosporine-induced acute nephrotoxicity". Life Sciences. 68 (10): 1181–90. doi:10.1016/s0024-3205(00)01028-6. PMID 11228102.
  8. ^ Chao YY, Jan CR (January 2004). "Effect of Y-24180 on Ca2+ movement and proliferation in renal tubular cells". Life Sciences. 74 (7): 923–33. doi:10.1016/j.lfs.2003.09.033. PMID 14659980.