Discontinued Product

4045 has been discontinued.
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PSI | CAS No. 158442-41-2 | Proteasome Inhibitors
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Description: Proteasome inhibitor. Also prevents activation of NF-κB

Chemical Name: N-[(Phenylmethoxy)carbonyl]-L-isoleucyl-L-α-glutamyl-tert-butyl ester-N-[(1S)-1-formyl-3-methylbutyl]-L-alaninamide

Purity: ≥90%

Product Details

Biological Activity

Proteasome inhibitor; inhibits chymotrypsin-like activity of the proteasome. Causes dopaminergic cell death in vitro. Prevents activation of NF-κB in response to TNF-α and okadaic acid (Cat. No. 1136) by inhibiting IκB-α degradation. Also inhibits NO production by LPS-activated macrophages.

Technical Data

Soluble to 30 mM in DMSO
Store at -20°C

The technical data provided above is for guidance only. For batch specific data refer to the Certificate of Analysis.
Tocris products are intended for laboratory research use only, unless stated otherwise.

Background References

  1. A proteasome inhibitor prevents activation of NF-κB and stabilizes a newly phosphorylated form of IκB-α that is still bound to NF-κB.
    Traenckner et al.
    EMBO J., 1994;13:5433
  2. An immunohistochemical and stereological analysis of PSI-induced nigral neuronal degeneration in the rat.
    Bukhatwa et al.
    J.Neurochem., 2009;109:52
  3. Inhibitors of the proteasome pathway interfere with induction of nitric oxide synthase in macrophages by blocking activation of transcription factor NF-κB.
    Griscavage et al.
    Proc.Natl.Acad.Sci.USA, 1996;93:3308

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