protease inhibitor

EST, (2S,3S)-trans-Epoxysuccinyl-L-leucylamido-3-methylbutane ethyl ester
Empirical Formula (Hill Notation):
CAS Number:
Molecular Weight:
MDL number:
PubChem Substance ID:

Quality Level

biological source

synthetic (organic)


≥98% (TLC)




methanol: water (1:1): 5 mg/mL, clear, colorless

storage temp.


SMILES string




InChI key


Gene Information

human ... CAPN1(823)


E-64d has been used as a lysosomal inhibitor in human acute promyelocytic leukemia NB4 cells and Huh-7 cells. It has also been used as a protease inhibitor in free calcium physiological tyrode solution for perfusion into the isolated heart samples.

Biochem/physiol Actions

E-64d is an epoxysuccinyl peptide and an inhibitor of cysteine protease cathepsin B, calpains 1 and 2. E-64d by its cathepsin B protease inhibition functionality, may serve as a potential drug for treating traumatic brain injury (TBI) and Alzheimer′s disease (AD). It inhibits gametocyte surface antigen resulting in a decreased oocyst production in Plasmodium falciparum.


13 - Non Combustible Solids

WGK Germany


Flash Point(F)

Not applicable

Flash Point(C)

Not applicable

Personal Protective Equipment

dust mask type N95 (US),Eyeshields,Gloves

Certificate of Analysis

Certificate of Origin

  1. How does the storage temperature relate to shipping conditions?

    The storage conditions that a Sigma-Aldrich catalog and label recommend for products are deliberately conservative. For many products, long-term storage at low temperatures will increase the time during which they are expected to remain in specification and therefore are labeled accordingly. Where short-term storage, shipping time frame, or exposure to conditions other than those recommended for long-term storage will not affect product quality, Sigma-Aldrich will ship at ambient temperature. The products sensitive to short-term exposure to conditions other than their recommended long-term storage are shipped on wet or dry ice. Ambient temperature shipping helps to control shipping costs for our customers. At any time, our customers can request wet- or dry-ice shipment, but the special handling is at customer expense if our product history indicates that the product is stable for regular shipment. See Shipping and Storage for more information.

  2. Which document(s) contains shelf-life or expiration date information for a given product?

    If available for a given product, the recommended re-test date or the expiration date can be found on the Certificate of Analysis.

  3. How do I get lot-specific information or a Certificate of Analysis?

    The lot specific COA document can be found by entering the lot number above under the "Documents" section.

  4. How do I find price and availability?

    There are several ways to find pricing and availability for our products. Once you log onto our website, you will find the price and availability displayed on the product detail page. You can contact any of our Customer Sales and Service offices to receive a quote.  USA customers:  1-800-325-3010 or view local office numbers.

  5. What is the Department of Transportation shipping information for this product?

    Transportation information can be found in Section 14 of the product's (M)SDS.To access the shipping information for this material, use the link on the product detail page for the product. 

  6. What can I dissolve Product E8640, E-64d, in?

    According to McGowan, E. B. et al., Biochem. Biophys. Res. Comm., 158(2), 432-435 (1989), this compound was dissolved in DMSO up to 200 mg/mL for use as an inhibitor of calpain in both intact and lysed platelets..

  7. Where can solutions of Product E8640, E-64d, be stored?

    According to McGowan, E. B. et al., Biochem. Biophys. Res. Comm., 158(2), 432-435 (1989), solutions made in DMSO were stored at -70°C.

  8. What is the difference between E-64, E-64c and E-64d?

    E-64c is a synthetic analog of E-64.  E-64d is the ethyl ester of E-64c.  E-64c is not cell permeable, but E-64d is cell permeable.  E-64d is hydrolyzed in cell culture to E-64c.   

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