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

MedKoo CAT#: 206031

CAS#: 22668-01-5

Description: Etanidazole (SR-2508) is a 2-nitroimidazole drug with radiosensitizing properties. Etanidazole depletes glutathione and inhibits glutathione transferase, thereby enhancing the cytotoxicity of ionizing radiation. This agent may also be useful as an imaging agent for identifying hypoxic, drug-resistant regions of primary tumors or metastases. Check for active clinical trials or closed clinical trials using this agent. (NCI Thesaurus).

Chemical Structure

CAS# 22668-01-5

Theoretical Analysis

MedKoo Cat#: 206031
Name: Etanidazole
CAS#: 22668-01-5
Chemical Formula: C7H10N4O4
Exact Mass: 214.0702
Molecular Weight: 214.18
Elemental Analysis: C, 39.25; H, 4.71; N, 26.16; O, 29.88

Size Price Shipping out time Quantity
10mg USD 425 Same day
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Pricing updated 2021-03-04. Prices are subject to change without notice.

Etanidazole, purity > 98%, is in stock. The same day shipping out after order is received.

Synonym: Etanidazole; SR2508; SR 2508; SR-2508

IUPAC/Chemical Name: N-(2-Hydroxyethyl)-2-(2-nitro-1H-imidazol-1-yl)acetamide


InChi Code: InChI=1S/C7H10N4O4/c12-4-2-8-6(13)5-10-3-1-9-7(10)11(14)15/h1,3,12H,2,4-5H2,(H,8,13)

SMILES Code: O=C(NCCO)CN1C=CN=C1[N+]([O-])=O

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, not in water

Shelf Life:
>5 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).

HS Tariff Code:

Certificate of Analysis:

Safety Data Sheet (SDS):

Handling Instructions:

Preparing Stock Solutions

The following data is based on the product molecular weight 214.18 Batch specific molecular weights may vary from batch to batch due to the degree 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 1.15 mL 5.76 mL 11.51 mL
5 mM 0.23 mL 1.15 mL 2.3 mL
10 mM 0.12 mL 0.58 mL 1.15 mL
50 mM 0.02 mL 0.12 mL 0.23 mL

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1: Yang Y, Jin C, Li H, He Y, Liu Z, Bai L, Dou K. Improved radiosensitizing effect of the combination of etanidazole and paclitaxel for hepatocellular carcinoma in vivo. Exp Ther Med. 2012 Feb;3(2):299-303. Epub 2011 Nov 24. PubMed PMID: 22969885; PubMed Central PMCID: PMC3438662.

2: Abe C, Uto Y, Nakae T, Shinmoto Y, Sano K, Nakata H, Teraoka M, Endo Y, Maezawa H, Masunaga S, Nakata E, Hori H. Evaluation of the in vivo radiosensitizing activity of etanidazole using tumor-bearing chick embryo. J Radiat Res. 2011;52(2):208-14. PubMed PMID: 21436611.

3: Gál M, Hromadová M, Pospísil L, Híves J, Sokolová R, Kolivoska V, Bulícková J. Voltammetry of hypoxic cells radiosensitizer etanidazole radical anion in water. Bioelectrochemistry. 2010 Jun;78(2):118-23. doi: 10.1016/j.bioelechem.2009.08.008. Epub 2009 Aug 23. PubMed PMID: 19733129.

4: Drzymala RE, Wasserman TH, Won M, Shaw E, Cmelak AJ, Loeffler J, Souhami L; Radiation Therapy Oncology Group. A phase I-B trial of the radiosensitizer: etanidazole (SR-2508) with radiosurgery for the treatment of recurrent previously irradiated primary brain tumors or brain metastases (RTOG Study 95-02). Radiother Oncol. 2008 Apr;87(1):89-92. doi: 10.1016/j.radonc.2008.02.006. Epub 2008 Mar 14. PubMed PMID: 18342381.

5: Jin C, Bai L, Wu H, Tian F, Guo G. Radiosensitization of paclitaxel, etanidazole and paclitaxel+etanidazole nanoparticles on hypoxic human tumor cells in vitro. Biomaterials. 2007 Sep;28(25):3724-30. Epub 2007 May 3. PubMed PMID: 17509678.

6: Kumar Naraharisetti P, Yung Sheng Ong B, Wei Xie J, Kam Yiu Lee T, Wang CH, Sahinidis NV. In vivo performance of implantable biodegradable preparations delivering Paclitaxel and Etanidazole for the treatment of glioma. Biomaterials. 2007 Feb;28(5):886-94. Epub 2006 Oct 25. PubMed PMID: 17067667.

7: Morilla MJ, Montanari J, Frank F, Malchiodi E, Corral R, Petray P, Romero EL. Etanidazole in pH-sensitive liposomes: design, characterization and in vitro/in vivo anti-Trypanosoma cruzi activity. J Control Release. 2005 Apr 18;103(3):599-607. PubMed PMID: 15820407.

8: Petray PB, Morilla MJ, Corral RS, Romero EL. In vitro activity of Etanidazole against the protozoan parasite Trypanosoma cruzi. Mem Inst Oswaldo Cruz. 2004 Mar;99(2):233-5. Epub 2004 Jun 24. PubMed PMID: 15250482.

9: Wang FJ, Wang CH. Etanidazole-loaded microspheres fabricated by spray-drying different poly(lactide/glycolide) polymers: effects on microsphere properties. J Biomater Sci Polym Ed. 2003;14(2):157-83. PubMed PMID: 12661666.

10: Tan WH, Lee T, Wang CH. Simulation of intratumoral release of Etanidazole: effects of the size of surgical opening. J Pharm Sci. 2003 Apr;92(4):773-89. PubMed PMID: 12661063.

Additional Information