WARNING: This product is for research use only, not for human or veterinary use.

MedKoo CAT#: 530905

CAS#: 66701-25-5

Description: E-64 is a potent, and irreversible inhibitor of cysteine proteases with IC50 values for inhibiting cathepsins K, S, and L, in vitro, are 1.4, 4.1, and 2.5 nM, respectively. E-64 improves the preimplantation development of bovine somatic cell nuclear transfer embryos.

Price and Availability


USD 190

USD 350

E-64, purity > 98%, is in stock. Current shipping out time is about 2 weeks after order is received. CoA, QC data and MSDS documents are available in one week after order is received.

Chemical Structure


Theoretical Analysis

MedKoo Cat#: 530905
Name: E-64
CAS#: 66701-25-5
Chemical Formula: C15H27N5O5
Exact Mass: 357.2012
Molecular Weight: 357.411
Elemental Analysis: C, 50.41; H, 7.61; N, 19.60; O, 22.38

Synonym: E-64; E 64; E64.

IUPAC/Chemical Name: 3-[[[(1S)-1-[[[4-[(aminoiminomethyl)amino]butyl]amino]carbonyl]-3-methylbutyl]amino]carbonyl]-(2S,3S)-oxiranecarboxylic acid


InChi Code: 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

SMILES Code: O=C([C@@H]1[C@@H](C(O)=O)O1)N[C@H](C(NCCCCNC(N)=N)=O)CC(C)C

Technical Data

Solid powder

>98% (or refer to the Certificate of Analysis)

Shipping Condition:
Shipped under ambient temperature as non-hazardous chemical. This product is stable enough for a few weeks during ordinary shipping and time spent in Customs.

Storage Condition:
Dry, dark and at 0 - 4 C for short term (days to weeks) or -20 C for long term (months to years).

Soluble in DMSO

Shelf Life:
>2 years if stored properly

Drug Formulation:
This drug may be formulated in DMSO

Stock Solution Storage:
0 - 4 C for short term (days to weeks), or -20 C for long term (months).

Harmonized System Code:


1: Blass G, Levchenko V, Ilatovskaya DV, Staruschenko A. Chronic cathepsin inhibition by E-64 in Dahl salt-sensitive rats. Physiol Rep. 2016 Sep;4(17). pii: e12950. doi: 10.14814/phy2.12950. PubMed PMID: 27597769; PubMed Central PMCID: PMC5027357.

2: Wilder CL, Walton C, Watson V, Stewart FA, Johnson J, Peyton SR, Payne CK, Odero-Marah V, Platt MO. Differential cathepsin responses to inhibitor-induced feedback: E-64 and cystatin C elevate active cathepsin S and suppress active cathepsin L in breast cancer cells. Int J Biochem Cell Biol. 2016 Oct;79:199-208. doi: 10.1016/j.biocel.2016.08.030. Epub 2016 Aug 31. PubMed PMID: 27592448; PubMed Central PMCID: PMC5067213.

3: Kershaw CM, Evans G, Rodney R, Maxwell WM. Papain and its inhibitor E-64 reduce camelid semen viscosity without impairing sperm function and improve post-thaw motility rates. Reprod Fertil Dev. 2016 May 9. doi: 10.1071/RD15261. [Epub ahead of print] PubMed PMID: 27156102.

4: Zhang Z, Huang Z, Dai H, Wei L, Sun S, Gao F. Therapeutic Efficacy of E-64-d, a Selective Calpain Inhibitor, in Experimental Acute Spinal Cord Injury. Biomed Res Int. 2015;2015:134242. doi: 10.1155/2015/134242. Epub 2015 Jul 9. PubMed PMID: 26240815; PubMed Central PMCID: PMC4512559.

5: Wadhawan M, Singh N, Rathaur S. Inhibition of cathepsin B by E-64 induces oxidative stress and apoptosis in filarial parasite. PLoS One. 2014 Mar 25;9(3):e93161. doi: 10.1371/journal.pone.0093161. eCollection 2014. PubMed PMID: 24667798; PubMed Central PMCID: PMC3965533.

6: Grozdanovic MM, Ostojic S, Aleksic I, Andjelkovic U, Petersen A, Gavrovic-Jankulovic M. Active actinidin retains function upon gastro-intestinal digestion and is more thermostable than the E-64-inhibited counterpart. J Sci Food Agric. 2014 Nov;94(14):3046-52. doi: 10.1002/jsfa.6656. Epub 2014 Apr 10. PubMed PMID: 24633720.

7: Carvalho TB, Oliveira-Sequeira TC, Guimarães S. In vitro antigiardial activity of the cysteine protease inhibitor E-64. Rev Inst Med Trop Sao Paulo. 2014 Jan-Feb;56(1):43-7. doi: 10.1590/S0036-46652014000100006. PubMed PMID: 24553607; PubMed Central PMCID: PMC4085827.

8: Min SH, Song BS, Yeon JY, Kim JW, Bae JH, Park SY, Lee YH, Chang KT, Koo DB. A cathepsin B inhibitor, E-64, improves the preimplantation development of bovine somatic cell nuclear transfer embryos. J Reprod Dev. 2014 Mar 7;60(1):21-7. Epub 2013 Nov 16. PubMed PMID: 24240170; PubMed Central PMCID: PMC3963301.

9: Tanabe F, Nakajima T, Ito M. The thiol proteinase inhibitor E-64-d ameliorates amyloid-β-induced reduction of sAPPα secretion by reversing ceramide-induced protein kinase C down-regulation in SH-SY5Y neuroblastoma cells. Biochem Biophys Res Commun. 2013 Nov 8;441(1):256-61. doi: 10.1016/j.bbrc.2013.10.045. Epub 2013 Oct 17. PubMed PMID: 24141119.

10: Yang WX, Zhang WH, Wu SY, Yao K, Liang GB, Li Y. [Effect of different molarity cathepsins specific inhibitor E-64 on dentin-resin bonding durability]. Zhonghua Kou Qiang Yi Xue Za Zhi. 2013 Jun;48(6):368-71. Chinese. PubMed PMID: 24120008.

11: Grozdanović MM, Drakulić BJ, Gavrović-Jankulović M. Conformational mobility of active and E-64-inhibited actinidin. Biochim Biophys Acta. 2013 Oct;1830(10):4790-9. doi: 10.1016/j.bbagen.2013.06.015. Epub 2013 Jun 23. PubMed PMID: 23803410.

12: Hussein EM, Dawoud HA, Salem AM, Atwa MM. Antiparasitic activity of cystine protease inhibitor E-64 against Giardia lamblia excystation in vitro and in vivo. J Egypt Soc Parasitol. 2009 Apr;39(1):111-9. PubMed PMID: 19530614.

13: Tanabe F, Kasai H, He L, Kin T, Fujikado T, Kumamoto T, Hara T, Iwata T, Ito M. Improvement of deficient natural killer activity and delayed bactericidal activity by a thiol proteinase inhibitor, E-64-d, in leukocytes from Chediak-Higashi syndrome patients in vitro. Int Immunopharmacol. 2009 Mar;9(3):366-70. doi: 10.1016/j.intimp.2009.01.003. Epub 2009 Jan 29. PubMed PMID: 19185618.

14: Morimoto M, Tanabe F, Kasai H, Ito M. Effect of a thiol proteinase inhibitor, E-64-d, on susceptibility to infection with Staphylococcus aureus in Chediak-Higashi syndrome (beige) mice. Int Immunopharmacol. 2007 Jul;7(7):973-80. Epub 2007 Apr 16. PubMed PMID: 17499200.

15: Gavira JA, González-Ramírez LA, Oliver-Salvador MC, Soriano-García M, García-Ruiz JM. Structure of the mexicain-E-64 complex and comparison with other cysteine proteases of the papain family. Acta Crystallogr D Biol Crystallogr. 2007 May;63(Pt 5):555-63. Epub 2007 Apr 21. PubMed PMID: 17452780.

16: Yoshifuji H, Umehara H, Maruyama H, Itoh M, Tanaka M, Kawabata D, Fujii T, Mimori T. Amelioration of experimental arthritis by a calpain-inhibitory compound: regulation of cytokine production by E-64-d in vivo and in vitro. Int Immunol. 2005 Oct;17(10):1327-36. PubMed PMID: 16176933.

17: Chatterjee PK, Todorovic Z, Sivarajah A, Mota-Filipe H, Brown PA, Stewart KN, Mazzon E, Cuzzocrea S, Thiemermann C. Inhibitors of calpain activation (PD150606 and E-64) and renal ischemia-reperfusion injury. Biochem Pharmacol. 2005 Apr 1;69(7):1121-31. PubMed PMID: 15763548.

18: Sarabia F, Sánchez-Ruiz A, Chammaa S. Stereoselective synthesis of E-64 and related cysteine proteases inhibitors from 2,3-epoxyamides. Bioorg Med Chem. 2005 Mar 1;13(5):1691-705. PubMed PMID: 15698787.

19: Yoshidome K, Kobae H, Yamamoto K, Sameshima K, Miyata K, Kawano Y. Effects of supplemental L-methionine on E-64 [trans-epoxysuccinyl-1-leucyl-amido (4-guanido) butane]-induced dysmorphology in rat embryos cultured in vitro. Congenit Anom (Kyoto). 2003 Dec;43(4):280-5. PubMed PMID: 15041779.

20: Takahashi S, Zhang HC, Hasegawa R, Karata K, Kita K, Wano C, Yamaguchi Y, Sugaya S, Nomura J, Ichinose M, Suzuki N. Increased levels of UV-induced protease activity in human UVAP-1 cells exposed to gravity-changing stress: involvement of E-64-sensitive proteases in suppression of UV mutagenicity. Cell Biol Int. 2003;27(1):53-60. PubMed PMID: 12713800.