E 64

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Cat.No. 5208 - E 64 | C15H27N5O5 | CAS No. 66701-25-5
Description: Potent and irreversible cysteine protease inhibitor
Chemical Name: (2S,3S)-3-[[[(1S)-1-[[[4-(Aminoiminomethyl)amino]butyl]amino]carbonyl]-3-methylbutyl]amino]carbonyl]-2-oxiranecarboxylic acid
Purity: ≥98% (HPLC)
Citations (1)

Biological Activity

Potent and irreversible cysteine protease inhibitor (IC50 values are 1.4, 2.5 and 4.1 nM for cathepsin K, L and S respectively. Also inhibits papain, calpain, cathepsin B and cathepsin H. Has no effect on serine proteases. Reduces HSC-3 tongue cancer cell invasion and induces oxidative stress and apoptosis in filarial parasites. Also inhibits autophagy-associated lysosomal degradation in vitro.

Technical Data

M. Wt 357.41
Formula C15H27N5O5
Storage Store at -20°C
Purity ≥98% (HPLC)
CAS Number 66701-25-5
PubChem ID 123985
Smiles O=[C@@](N[C@H]([C@](NCCCCNC(N)=N)=O)CC(C)C)[C@@H]1[C@@H](C(O)=O)O1

The technical data provided above is for guidance only. For batch specific data refer to the Certificate of Analysis.

All Tocris products are intended for laboratory research use only.

Solubility Data

Solvent Max Conc. mg/mL Max Conc. mM
water 7.15 20

Preparing Stock Solutions

The following data is based on the product molecular weight 357.41. Batch specific molecular weights may vary from batch to batch due to solvent of hydration, which will affect the solvent volumes required to prepare stock solutions.

Select a batch to recalculate based on the batch molecular weight:
Concentration / Solvent Volume / Mass 1 mg 5 mg 10 mg
1 mM 2.8 mL 13.99 mL 27.98 mL
5 mM 0.56 mL 2.8 mL 5.6 mL
10 mM 0.28 mL 1.4 mL 2.8 mL
50 mM 0.06 mL 0.28 mL 0.56 mL

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Product Datasheets

Certificate of Analysis / Product Datasheet
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Safety Datasheet


References are publications that support the products' biological activity.

Susa et al (2004) Human primary osteoclasts: in vitro generation and applications as pharmacological and clinical assay. J.Transl.Med. 2 6 PMID: 15025786

Bitu et al (2013) Cathepsin K is present in invasive oral tongue squamous cell carcinoma in vivo and in vitro. PLoS ONE 8 e70925 PMID: 23951042

Wadhawan et al (2014) Inhibition of cathepsin B by E-64 induces oxidative stress and apoptosis in filarial parasite. PLoS ONE 9 e93161 PMID: 24667798

Zhao et al (2010) Cytosolic FoxO1 is essential for the induction of autophagy and tumour suppressor activity. Nat.Cell.Biol. 12 665 PMID: 20543840

If you know of a relevant reference for E 64, please let us know.

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Keywords: E 64, supplier, E64, potent, irreversible, natural, cysteine, protease, inhibitors, inhibits, cathepsin, K, L, S, B, H, calpain, papain, Cathepsin, Calpains, Calcium-Sensitive, Proteases, Cathepsin, Tocris Bioscience

1 Citation for E 64

Citations are publications that use Tocris products. Selected citations for E 64 include:

Lee et al (2015) Tricyclic Antidepressants Amitriptyline and Desipramine Induced Neurotoxicity Associated with Parkinson's Disease. PLoS One 38 734 PMID: 26242194

Do you know of a great paper that uses E 64 from Tocris? If so please let us know.

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New Product Guide

New Product Guide (Spring/Summer 2017)

Our new product guide highlights over 130 new products added to the Tocris Bioscience range during the first half of 2017.

  • 7-TM Receptors
  • Enzymes
  • Enzyme-Linked Receptors
  • Ion Channels
  • Nuclear Receptors
  • Transporters
  • Apoptosis
  • Cell Metabolism
  • Epigenetics
  • Fluorescent Imaging
  • Signal Transduction
  • Stem Cells

Pathways for E 64


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