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MedKoo CAT#: 562345

CAS#: 273930-52-2

Description: NS4591 is a molulator of SK-IK channels [small- and intermediate-conductance Ca2(+) -activated K(+) channels].

Price and Availability

Size Price Shipping out time Quantity
Inquire bulk and customized quantity

Pricing updated 2020-08-08. Prices are subject to change without notice.

NS4591 is not in stock, may be available through custom synthesis. For cost-effective reason, minimum 1 gram order is requested. The product will be characterized by NMR, HPLC and MS analysis. Purity (HPLC) is usually >98%. CoA, QC data, MSDS will be provided when product is successfully made. The estimated lead time is 2-3 months. Please send email to sales@medkoo.com to inquire quote.

Chemical Structure


Theoretical Analysis

MedKoo Cat#: 562345
Name: NS4591
CAS#: 273930-52-2
Chemical Formula: C11H12Cl2N2O
Exact Mass: 258.0327
Molecular Weight: 259.13
Elemental Analysis: C, 50.99; H, 4.67; Cl, 27.36; N, 10.81; O, 6.17

Synonym: NS4591; NS-4591; NS 4591;

IUPAC/Chemical Name: 4,5-Dichloro-1,3-diethyl-1,3-dihydro-benzoimidazol-2-one


InChi Code: InChI=1S/C11H12Cl2N2O/c1-3-14-8-6-5-7(12)9(13)10(8)15(4-2)11(14)16/h5-6H,3-4H2,1-2H3


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).

HS Tariff Code:


1: Comerma-Steffensen SG, Carvacho I, Hedegaard ER, Simonsen U. Small and Intermediate Calcium-Activated Potassium Channel Openers Improve Rat Endothelial and Erectile Function. Front Pharmacol. 2017 Sep 20;8:660. doi: 10.3389/fphar.2017.00660. eCollection 2017. PubMed PMID: 28993731; PubMed Central PMCID: PMC5619997.

2: Kroigaard C, Kudryavtseva O, Dalsgaard T, Wandall-Frostholm C, Olesen SP, Simonsen U. K(Ca)3.1 channel downregulation and impaired endothelium-derived hyperpolarization-type relaxation in pulmonary arteries from chronically hypoxic rats. Exp Physiol. 2013 Apr;98(4):957-69. doi: 10.1113/expphysiol.2012.066340. Epub 2012 Dec 13. PubMed PMID: 23243147.

3: Rosenbaum ST, Larsen T, Joergensen JC, Bouchelouche PN. Relaxant effect of a novel calcium-activated potassium channel modulator on human myometrial spontaneous contractility in vitro. Acta Physiol (Oxf). 2012 Jun;205(2):247-54. doi: 10.1111/j.1748-1716.2011.02384.x. Epub 2011 Dec 22. PubMed PMID: 22099068.

4: Nielsen JS, Rode F, Rahbek M, Andersson KE, Rønn LC, Bouchelouche K, Nordling J, Bouchelouche P. Effect of the SK/IK channel modulator 4,5-dichloro-1,3-diethyl-1,3-dihydro-benzoimidazol-2-one (NS4591) on contractile force in rat, pig and human detrusor smooth muscle. BJU Int. 2011 Sep;108(5):771-7. doi: 10.1111/j.1464-410X.2010.10019.x. Epub 2011 Jan 11. PubMed PMID: 21223472.

5: Hougaard C, Fraser MO, Chien C, Bookout A, Katofiasc M, Jensen BS, Rode F, Bitsch-Nørhave J, Teuber L, Thor KB, Strøbaek D, Burgard EC, Rønn LC. A positive modulator of K Ca 2 and K Ca 3 channels, 4,5-dichloro-1,3-diethyl-1,3-dihydro-benzoimidazol-2-one (NS4591), inhibits bladder afferent firing in vitro and bladder overactivity in vivo. J Pharmacol Exp Ther. 2009 Jan;328(1):28-39. doi: 10.1124/jpet.108.143123. Epub 2008 Sep 26. PubMed PMID: 18820135.