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532281 IRE1 Inhibitor IV, KIRA6 - Calbiochem


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      OverviewA cell-permeable, bioavailable, non-toxic, imidazopyrazinyl-naphthalenyl-phenylurea based compound that acts as a potent, ATP-competitive, reversible, and selective inhibitor of IRE1α kinase (IC50 = 600 nM). Exhibits good selectivity over ERK2, JNK2, JNK3, PIM1, PAK4, and PKA (IC50 > 10 µM). Stabilizes the kinase domain of IRE1α in an inactive conformation and blocks its oligomerization and thereby reduces RNase domain activity. Shown to block brefeldin A-(Cat. Nos. 203729 & 500583) induced ER stress and apoptosis in INS-1 cells and tunicamycin (Cat. Nos. 654380 & 504570)-induced apoptosis in β-cells derived from C57BL/6 mice. Affords significant cytoprotection in combination with STF-083010 (Cat. No. 412510, 1 µM) and KIRA6 (50 nM). Systemic administration of KIRA6 in the Akita diabetic mice is shown to reduce their blood glucose levels, improve glucose tolerance, and conserve their β-cell function. Preserves photoreceptor function in a transgenic rat model (P23H) of chronic ER stress-induced retinal degeneration, when administered intravitreally. Displays desirable pharmacokinetic properties with t1/2 = 3.9 h and moderate clearance rate of 22.4 ml/min/kg in BABL/c mice (10 mg/kg, i.p.).

      Please note that the molecular weight for this compound is batch-specific due to variable water content.
      Catalogue Number532281
      Brand Family Calbiochem®
      Synonyms1-(4-(8-Amino-3-tert-butylimidazo[1,5-a]pyrazin-1-yl)naphthalen-1-yl)-3-(3-(trifluoromethyl)phenyl)urea, Kinase-Inhibiting RNase Attenuator 6, IRE1α Kinase Inhibitor
      ReferencesGhosh, R., et al. 2014. Cell. 158, 534.
      Product Information
      FormOff-white to brown powder
      Hill FormulaC₂₈H₂₅F₃N₆O
      Chemical formulaC₂₈H₂₅F₃N₆O
      Quality LevelMQ100
      Biological Information
      Primary TargetIRE1α kinase
      Purity≥95% by HPLC
      Physicochemical Information
      Cell permeableY
      Materials Information
      Toxicological Information
      Safety Information according to GHS
      Safety Information
      Product Usage Statements
      Storage and Shipping Information
      Ship Code Ambient Temperature Only
      Toxicity Standard Handling
      Storage +2°C to +8°C
      Protect from Light Protect from light
      Do not freeze Ok to freeze
      Special InstructionsFollowing reconstitution, aliquot and freeze (-20°C). Stock solutions are stable for up to 6 months at -20°C.
      Packaging Information
      Packaged under inert gas Packaged under inert gas
      Transport Information
      Supplemental Information
      Global Trade Item Number
      Catalog Number GTIN
      5.32281.0001 04055977260038


      IRE1 Inhibitor IV, KIRA6 - Calbiochem SDS


      Safety Data Sheet (SDS) 


      Reference overview
      Ghosh, R., et al. 2014. Cell. 158, 534.
      Data Sheet

      Note that this data sheet is not lot-specific and is representative of the current specifications for this product. Please consult the vial label and the certificate of analysis for information on specific lots. Also note that shipping conditions may differ from storage conditions.

      Revision16-November-2016 JSW
      Synonyms1-(4-(8-Amino-3-tert-butylimidazo[1,5-a]pyrazin-1-yl)naphthalen-1-yl)-3-(3-(trifluoromethyl)phenyl)urea, Kinase-Inhibiting RNase Attenuator 6, IRE1α Kinase Inhibitor
      DescriptionA cell-permeable imidazopyrazinyl-naphthalenyl-phenylurea compound that acts as an IRE1α-selective type II kinase inhibitor (IC50 = 0.6 µM; IC50 >10 µM against Erk2, JNK2, JNK3, Pak4, Pim1, PKA) by targeting ATP-binding site in its inactive conformation. Stabilizing IRE1α kinase domain in an inactive conformation by KIRA6 prevents IRE1α oligomerization and subsequent RNase domain activity induction, resulting in effective inhibition against stress-induced cellular IRE1α oligomerization (5 mM DTT for 6 h +/1 µM KIRA6) & phosphorylation (1 h 10 µM; KIRA6 pretretament prior to 1 µM Tg/586005 & 586006 for 2 h), XBP1 mRNA splicing (IC50 = 2 µM; 1 h KIRA6 pretreatment prior to 0.5 µg/mL Tm/654380 & 504570 for 8 h), Ins1 mRNA degradation (IC50 = 0.5 µM; 1 hKIRA6 pretretament prior to 0.5 µg/mL Tm for 12 h), and apoptosis (% annexin V + cells = 22% vs. 60% post 72 h 0.25 µg/mL BFA/203729 & 500583 treatment with or without 0.5 µM KIRA6; No BFA control = 16%) in rat insulinoma INS-1 cultures without significant cytotoxicity (up to 10 µM for 72 h). Blockage of stress-induced apoptosis is similarly observed in primary human & murine islets cultures (0.5 µg/mL Tm for 16 h +/ 0.5 µM KIRA6) with a concomitant recovery of glucose-stimulated insulin secretion. KIRA6 is bioavailable via intraperitoneal injection in mice (Plasma Cmax/t1/2/AUC0-24 h = 3.3 µM/3.90 h/14.3 µM·h; 10 mg/kg BALB/c i.p.) in vivo with no apparent animal toxicity and is efficacious (5 or 10 mg/kg/12 h for 33 to 37 days) in reducing high blood glucose level due to chronic ER stress-induced β cell loss among Ins2+/Akita mice expressing proinsulin C96Y mutant with oxidative folding defect. Likewise, KIRA6 co-administration is shown to significantly reduce Rhodopsin mRNA degradation 96 h post Tm intraveal injection (2 µL per eye, final vitreal [Tm] & [KIRA6] = 20 µg/µL & 10 µM, respectively) in a rat model of acute photoreceptor loss in vivo, despite a rapid vitreal clearance (t1/2 <60 h). Synergistic cytoprotection is demonstrated when combined with STF-083010 (Cat. No. 412510) that covalently modifies IRE1 RNase domain Lys907 in Tm-treated INS-1 cultures.
      FormOff-white to brown powder
      Intert gas (Yes/No) Packaged under inert gas
      Chemical formulaC₂₈H₂₅F₃N₆O
      Purity≥95% by HPLC
      SolubilityDMSO (50 mg/ml). Use only fresh DMSO for reconstitution.
      Storage Protect from light
      +2°C to +8°C
      Do Not Freeze Ok to freeze
      Special InstructionsFollowing reconstitution, aliquot and freeze (-20°C). Stock solutions are stable for up to 6 months at -20°C.
      Toxicity Standard Handling
      ReferencesGhosh, R., et al. 2014. Cell. 158, 534.