Efaproxiral sodium

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MedKoo CAT#: 330025

CAS#: 170787-99-2 (sodium)

Description: Efaproxiral, also known as RSR13, is an analogue of the cholesterol drug bezafibrate developed for the treatment of depression, traumatic brain injury, ischemia, stroke, myocardial infarction, diabetes, hypoxia, sickle cell disease, hypercholesterolemia and as a radio sensitiser. One use for efaproxiral is to increase the efficacy of certain chemotherapy drugs which have reduced efficacy against hypoxic tumours, and can thus be made more effective by increased offloading of oxygen into the tumour tissues

Chemical Structure

Efaproxiral sodium
CAS# 170787-99-2 (sodium)

Theoretical Analysis

MedKoo Cat#: 330025
Name: Efaproxiral sodium
CAS#: 170787-99-2 (sodium)
Chemical Formula: C20H22NNaO4
Exact Mass:
Molecular Weight: 363.3888
Elemental Analysis: C, 66.11; H, 6.10; N, 3.85; Na, 6.33; O, 17.61

Price and Availability

Size Price Availability Quantity
250.0mg USD 350.0 2 weeks
500.0mg USD 650.0 2 weeks
1.0g USD 950.0 2 weeks
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Related CAS #: 170787-99-2 (sodium)   131179-95-8 (free acid)    

Synonym: Efaproxiral sodium; RSR 13; RSR-13; RSR13 sodium

IUPAC/Chemical Name: Sodium 2-[4-[2-[(3,5-Dimethylphenyl)amino]-2-oxoethyl]phenoxy]-2-methylpropanoate


InChi Code: InChI=1S/C20H23NO4.Na/c1-13-9-14(2)11-16(10-13)21-18(22)12-15-5-7-17(8-6-15)25-20(3,4)19(23)24;/h5-11H,12H2,1-4H3,(H,21,22)(H,23,24);/q;+1/p-1

SMILES Code: CC(C)(OC1=CC=C(CC(NC2=CC(C)=CC(C)=C2)=O)C=C1)C([O-])=O.[Na+]

Appearance: Solid powder

Purity: >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).

Solubility: Soluble in DMSO

Shelf Life: >3 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: 2934.99.9001

Preparing Stock Solutions

The following data is based on the product molecular weight 363.3888 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.

Recalculate based on batch purity %
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: Watanabe A, Poole DC, Kano Y. The effects of RSR13 on microvascular Po(2) kinetics and muscle contractile performance in the rat arterial ligation model of peripheral arterial disease. J Appl Physiol (1985). 2017 Oct 1;123(4):764-772. doi: 10.1152/japplphysiol.00257.2017. Epub 2017 Jun 15. PubMed PMID: 28620055.

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11: Gustafsson T, Pontén F, Seeberger PH. Trimethylaluminium mediated amide bond formation in a continuous flow microreactor as key to the synthesis of rimonabant and efaproxiral. Chem Commun (Camb). 2008 Mar 7;(9):1100-2. doi: 10.1039/b719603b. Epub 2008 Feb 1. PubMed PMID: 18292903.

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13: Hou H, Khan N, Grinberg OY, Yu H, Grinberg SA, Lu S, Demidenko E, Steffen RP, Swartz HM. The effects of Efaproxyn (efaproxiral) on subcutaneous RIF-1 tumor oxygenation and enhancement of radiotherapy-mediated inhibition of tumor growth in mice. Radiat Res. 2007 Aug;168(2):218-25. PubMed PMID: 17638413.

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