CK-869 is a small molecule inhibitor of human and bovine actin-related protein 2/3 (Arp2/3) complex which is a seven-subunit assembly that nucleates branched actin filaments. The mode of action of CK-869 is to bind to Arp2/3 complex and inhibit nucleation. CK-869 binds to a serendipitous pocket on Arp3 and allosterically destabilizes the short pitch Arp3-Arp2 interface. These results provide key insights into the relationship between conformation and activity in Arp2/3 complex and will be critical for interpreting the influence of the inhibitors on actin filament networks in vivo.

Physicochemical Properties

Molecular Formula	C17H16BRNO3S
Molecular Weight	394.28
Exact Mass	393.003
CAS #	388592-44-7
Related CAS #	388592-44-7
PubChem CID	3574452
Appearance	White to off-white solid powder
LogP	4.309
Hydrogen Bond Donor Count	0
Hydrogen Bond Acceptor Count	4
Rotatable Bond Count	4
Heavy Atom Count	23
Complexity	425
Defined Atom Stereocenter Count	0
InChi Key	MVWNPZYLNLATCH-UHFFFAOYSA-N
InChi Code	InChI=1S/C17H16BrNO3S/c1-21-13-6-7-14(15(9-13)22-2)19-16(20)10-23-17(19)11-4-3-5-12(18)8-11/h3-9,17H,10H2,1-2H3
Chemical Name	2-(3-Bromophenyl)-3-(2,4-dimethoxyphenyl)-4-thiazolidinone
Synonyms	CK-869; CK 869; CK869; CK-0157869; CK 0157869; CK0157869
HS Tariff Code	2934.99.9001
Storage	Powder-20°C 3 years 4°C 2 years In solvent -80°C 6 months -20°C 1 month
Shipping Condition	Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Biological Activity

ln Vitro	CK-869 is an Actin-Related Protein 2/3 (ARP2/3) complex inhibitor, with an IC50 of 7 μM[1]. CK-869 strongly inhibits MT polymerization even at a dose of 25 μM[2].
ln Vivo
Animal Protocol
References	[1]. Small molecules CK-666 and CK-869 inhibit actin-related protein 2/3 complex by blocking an activating conformational change. Chem Biol. 2013 May 23;20(5):701-12. [2]. Use of CK-548 and CK-869 as Arp2/3 complex inhibitors directly suppresses microtubule assembly both in vitro and in vivo. Biochem Biophys Res Commun. 2018 Feb 12;496(3):834-839.

Solubility Data

Solubility (In Vitro)

DMSO: 10 mM Water:< 1mg/mL Ethanol:< 1mg/mL

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.5 mg/mL (6.34 mM) (saturation unknown) in 10% DMSO + 40% PEG300 + 5% Tween80 + 45% Saline (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 400 μL PEG300 and mix evenly; then add 50 μL Tween-80 to the above solution and mix evenly; then add 450 μL normal saline to adjust the volume to 1 mL. Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH₂ O to obtain a clear solution. Solubility in Formulation 2: ≥ 2.5 mg/mL (6.34 mM) (saturation unknown) in 10% DMSO + 90% (20% SBE-β-CD in Saline) (add these co-solvents sequentially from left to right, and one by one), suspension solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of 20% SBE-β-CD physiological saline solution and mix evenly. Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution. Solubility in Formulation 3: ≥ 2.5 mg/mL (6.34 mM) (saturation unknown) in 10% DMSO + 90% Corn Oil (add these co-solvents sequentially from left to right, and one by one), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 25.0 mg/mL clear DMSO stock solution to 900 μL of corn oil and mix evenly.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	2.5363 mL	12.6813 mL	25.3627 mL
	5 mM	0.5073 mL	2.5363 mL	5.0725 mL
	10 mM	0.2536 mL	1.2681 mL	2.5363 mL

*Note: Please select an appropriate solvent for the preparation of stock solution based on your experiment needs. For most products, DMSO can be used for preparing stock solutions (e.g. 5 mM, 10 mM, or 20 mM concentration); some products with high aqueous solubility may be dissolved in water directly. Solubility information is available at the above Solubility Data section. Once the stock solution is prepared, aliquot it to routine usage volumes and store at -20°C or -80°C. Avoid repeated freeze and thaw cycles.