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

MedKoo CAT#: 584807

CAS#: 79811-16-8

Description: WW-781 is used to measure action potential propagation in the heart.

Chemical Structure

CAS# 79811-16-8

Theoretical Analysis

MedKoo Cat#: 584807
Name: WW-781
CAS#: 79811-16-8
Chemical Formula: C27H32N4O7S
Exact Mass: 556.1992
Molecular Weight: 556.634
Elemental Analysis: C, 58.26; H, 5.79; N, 10.07; O, 20.12; S, 5.76

Price and Availability

This product is not in stock, which may be available by custom synthesis. For cost-effective reason, minimum order is 1g (price is usually high, lead time is 2~3 months, depending on the technical challenge). Quote less than 1g will not be provided. To request quote, please email to sales @medkoo.com or click below button.
Note: Price will be listed if it is available in the future.

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Synonym: WW-781; NK 2935; WW 781; WW781

IUPAC/Chemical Name: Benzenesulfonic acid, 4-(4-(5-(1,3-dibutyltetrahydro-2,4,6-trioxo-5(2H)-pyrimidinylidene)-1,3-pentadienyl)-4,5-dihydro-3-methyl-5-oxo-1H-pyrazol-1-yl)-


InChi Code: InChI=1S/C27H32N4O7S/c1-4-6-17-29-24(32)23(25(33)30(27(29)35)18-7-5-2)12-10-8-9-11-22-19(3)28-31(26(22)34)20-13-15-21(16-14-20)39(36,37)38/h8-16,22H,4-7,17-18H2,1-3H3,(H,36,37,38)/b10-8+,11-9+

SMILES Code: O=S(C1=CC=C(N2N=C(C)C(/C=C/C=C/C=C(C(N3CCCC)=O)\C(N(CCCC)C3=O)=O)C2=O)C=C1)(O)=O

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 556.634 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: Raha NM, Spinelli LJ, Knauf PA. WW-781, a potent reversible inhibitor of red cell Cl- flux, binds to band 3 by a two-step mechanism. Am J Physiol. 1993 Aug;265(2 Pt 1):C521-32. PubMed PMID: 8368278.

2: Freedman JC, Novak TS. Membrane potentials associated with Ca-induced K conductance in human red blood cells: studies with a fluorescent oxonol dye, WW 781. J Membr Biol. 1983;72(1-2):59-74. PubMed PMID: 6406671.

3: Mizutani K, Shimoi T, Kitamura Y, Ogawa H, Oka K. Identification of two types of synaptic activity in the earthworm nervous system during locomotion. Neuroscience. 2003;121(2):473-8. PubMed PMID: 14522005.

4: Perez-Cornejo P, Arreola J, Law FY, Schultz JB, Knauf PA. Volume-sensitive chloride channels do not mediate activation-induced chloride efflux in human neutrophils. J Immunol. 2004 Jun 1;172(11):6988-93. PubMed PMID: 15153519.

5: Konnerth A, Orkand PM, Orkand RK. Optical recording of electrical activity from axons and glia of frog optic nerve: potentiometric dye responses and morphometrics. Glia. 1988;1(3):225-32. PubMed PMID: 2852172.

6: Wolfbeis OS, Opitz D, Werner T, Ouart A. Chiroptic recognition of potassium ion. J Mol Recognit. 2001 Jan-Feb;14(1):13-7. PubMed PMID: 11180558.

7: Dillon S, Morad M. A new laser scanning system for measuring action potential propagation in the heart. Science. 1981 Oct 23;214(4519):453-6. PubMed PMID: 6974891.

8: Fillette F, Nassif G, Lascault G. [Electric activation of the heart using laser spectrometry. 1. Study of transmembrane action potentials using optical technics]. Arch Mal Coeur Vaiss. 1985 Sep;78(9):1418-24. French. PubMed PMID: 3936445.

9: Pratap PR, Novak TS, Freedman JC. Two mechanisms by which fluorescent oxonols indicate membrane potential in human red blood cells. Biophys J. 1990 Apr;57(4):835-49. PubMed PMID: 1693090; PubMed Central PMCID: PMC1280784.

10: Fillette F, Nassif G. A study of electrical activation of the heart by laser spectrometry. An optical study of cellular action potentials. Int J Card Imaging. 1987;2(3):165-72. PubMed PMID: 3429940.

11: Sakai T. Wavelength dependence of optical action potentials in the isolated rat atrium. Jpn J Physiol. 2005 Dec;55(6):389-93. Epub 2005 Nov 16. PubMed PMID: 16285889.

12: Sato Y, Fujino M. New optical spike in frog twitch muscle fibers injected with a potential probe dye NK2935. Jpn J Physiol. 1986;36(6):1203-24. PubMed PMID: 3599554.

13: Bowmaster TA, Davis CC, Krauthamer V. Excitation and detection of action potential-induced fluorescence changes through a single monomode optical fiber. Biochim Biophys Acta. 1991 Jan 10;1091(1):9-14. PubMed PMID: 1995070.

14: George EB, Nyirjesy P, Basson M, Ernst LA, Pratap PR, Freedman JC, Waggoner AS. Impermeant potential-sensitive oxonol dyes: I. Evidence for an "on-off" mechanism. J Membr Biol. 1988 Aug;103(3):245-53. PubMed PMID: 3184175.