Israpafant

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]

Israpafant

Legal status
Legal status	US: Investigational New Drug
Identifiers
IUPAC name (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	117279-73-9 Y
PubChem CID	636426
ChemSpider	552203
UNII	O3MCV749SW
CompTox Dashboard (EPA)	DTXSID001102657
Chemical and physical data
Formula	C28H29ClN4S
Molar mass	489.08 g·mol−1
3D model (JSmol)	Interactive image
SMILES 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 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

See also

• JQ1