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E3132

E-64

synthetic (organic), ≥98% (HPLC), cysteine protease inhibitor, powder

Synonym(s):

trans-Epoxysuccinyl-L-leucylamido(4-guanidino)butane, L-trans-3-Carboxyoxiran-2-carbonyl-L-leucylagmatine, N-(trans-Epoxysuccinyl)-L-leucine 4-guanidinobutylamide

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Size/SKUAvailabilityPrice
1 mg
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$88.70
5 mg

Available to ship onSeptember 24, 2026fromMILWAUKEE

$307.00
10 mg

Available to ship onSeptember 24, 2026fromMILWAUKEE

$458.00
25 mg

Available to ship onSeptember 24, 2026fromMILWAUKEE

$1,150.00
50 mg

Available to ship onSeptember 24, 2026fromMILWAUKEE

$1,590.00

About This Item

Empirical Formula (Hill Notation):
C15H27N5O5
CAS Number:
66701-25-5
Molecular Weight:
357.41
NACRES:
NA.77
PubChem Substance ID:
24278411
UNSPSC Code:
12352202
MDL number:
MFCD00080261
Beilstein/REAXYS Number:
1405664

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Product Name

E-64, protease inhibitor

biological source

synthetic (organic)

Quality Segment

assay

≥98% (HPLC)

form

powder

solubility

water: 20 mg/mL, clear, colorless to faintly yellow

storage temp.

2-8°C

SMILES string

CC(C)C[C@H](NC(=O)[C@@H]1O[C@H]1C(O)=O)C(=O)NCCCCNC(N)=N

InChI

1S/C15H27N5O5/c1-8(2)7-9(20-13(22)10-11(25-10)14(23)24)12(21)18-5-3-4-6-19-15(16)17/h8-11H,3-7H2,1-2H3,(H,18,21)(H,20,22)(H,23,24)(H4,16,17,19)/t9-,10+,11+/m0/s1

InChI key

LTLYEAJONXGNFG-HBNTYKKESA-N

General description

E-64 is a cysteine protease inhibitor that was isolated from the mold Aspergillus japonicus TPR-64. E-64 is also known as N-[N-(L-3-trans-carboxyoxiran-2-carbonyl)-L-leucyl]-agmatine. E-64 effectively inhibits various cysteine proteases, in particular:
  • cathepsin K
  • cathepsin L
  • cathepsin S
E-64 also acts against other enzymes, such as:
  • calpain
  • cathepsin B
  • cathepsin H
  • papain

Application

E-64 is an effective ligand for affinity purification of cysteine proteases. When coupled to a thiolated affinity matrix, binding is no longer irreversible, but specificity is retained.

Biochem/physiol Actions

E-64 is an irreversible, potent, and highly selective cysteine protease inhibitor. E-64 does not react with the functional thiol group of non-protease enzymes, such as L-lactate dehydrogenase or creatine kinase. E-64 will not inhibit serine proteases (except trypsin) like other cysteine protease inhibitors, leupeptin and antipain. The trans-epoxysuccinyl group (active moiety) of E-64 irreversibly binds to an active thiol group in many cysteine proteases, such as papain, actinidase, and cathepsins B, H, and L to form a thioether linkage. E-64 is a very useful cysteine protease inhibitor for use in in vivo studies because it has a specific inhibition, it is permeable in cells and tissues and has low toxicity.
Effective irreversible inhibitor of cysteine proteases that does not affect cysteine residues in other enzymes or react with low molecular weight thiols such as calpain and cathepsin B. Effective concentration 1-10 μM.

Preparation Note

E-64 is soluble in water. A 20 mg/ml solution can be prepared in water (heat may be needed). A suggested stock solution is a 1 mM aqueous solution. The effective concentration for use as a protease inhibitor is 1 to10 μM. Aqueous stock solutions are stable for months at -20 °C. Diluted solutions are stable for days at neutral pH. E-64 is stable from pH 2-10, but is unstable in ammonia or in HCl. E-64 is also soluble in DMSO, a 10 mM solution can be prepared in dry DMSO and stored at -20 °C. Subsequent dilutions were in culture medium. Solutions for injection were prepared by dissolving E-64 in 0.9% sodium chloride or in a minimum amount of saturated sodium bicarbonate followed by dilution with 0.9% sodium chloride (after adjusting the pH to 7.0 with acetic acid).

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This Item
324890E8640SAE0154
E-64 protease inhibitor

Sigma-Aldrich

E3132

E-64

E-64 Protease Inhibitor The E-64 Protease Inhibitor, also referenced under CAS 66701-25-5, controls the biological activity of E-64 Protease. This small molecule/inhibitor is primarily used for Protease Inhibitors applications.

Sigma-Aldrich

324890

E-64 Protease Inhibitor

E-64d protease inhibitor

Sigma-Aldrich

E8640

E-64d

E64 Ready Made solution Non-freezing solution, 1 mg/mL

Sigma-Aldrich

SAE0154

E64 Ready Made solution

description

protease inhibitor

description

The E-64 Protease Inhibitor, also referenced under CAS 66701-25-5, controls the biological activity of E-64 Protease. This small molecule/inhibitor is primarily used for Protease Inhibitors applications.

description

protease inhibitor

description

Non-freezing solution, 1 mg/mL

biological source

synthetic (organic)

biological source

-

biological source

synthetic (organic)

biological source

-

assay

≥98% (HPLC)

assay

≥98% (HPLC)

assay

≥98% (TLC)

assay

-

Quality Level

300

Quality Level

200

Quality Level

200

Quality Level

200

form

powder

form

solid

form

powder

form

ready-to-use solution

storage temp.

2-8°C

storage temp.

−20°C

storage temp.

−20°C

storage temp.

−20°C

solubility

water: 20 mg/mL, clear, colorless to faintly yellow

solubility

water: 20 mg/mL, DMSO: 25 mg/mL

solubility

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

solubility

-

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Storage Class

11 - Combustible Solids

Flash Point (°F)

Not applicable

Flash Point (°C)

Not applicable

PPE (personal protective equipment)

Eyeshields, Gloves, type N95 (US)

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