A-3 HCl is a potent, cell-penetrable, reversible, ATP-competitive, non-selective antagonist targeting multiple kinases. A-3 HCl is an inhibitor (blocker/antagonist) of PKA (Ki=4.3 µM), casein kinase II (Ki=5.1 µM) and myosin light chain kinase (MLCK) (Ki=7.4 µM). A-3 HCl also inhibits PKC and casein kinase I activities with Ki of 47 µM and 80 µM, respectively.

Physicochemical Properties

Molecular Formula	C12H13N2O2SCL.HCL
Molecular Weight	321.22276
Exact Mass	320.015
CAS #	78957-85-4
PubChem CID	9861903
Appearance	Light yellow to light brown solid powder
Melting Point	173-176ºC
LogP	4.704
Hydrogen Bond Donor Count	3
Hydrogen Bond Acceptor Count	4
Rotatable Bond Count	4
Heavy Atom Count	19
Complexity	369
Defined Atom Stereocenter Count	0
InChi Key	VWAGIWCLJAQLAL-UHFFFAOYSA-N
InChi Code	InChI=1S/C12H13ClN2O2S.ClH/c13-11-5-1-4-10-9(11)3-2-6-12(10)18(16,17)15-8-7-14;/h1-6,15H,7-8,14H2;1H
Chemical Name	N-(2-aminoethyl)-5-chloronaphthalene-1-sulfonamide;hydrochloride
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 Note: Please store this product in a sealed and protected environment, avoid exposure to moisture.
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	At a Ki value of 7.4 μM, A-3 hydrochloride competitively inhibits MLC kinase in comparison to ATP. A-3 exhibits competitive inhibition against cAMP-dependent protein kinase, cGMP-dependent protein kinase, protein kinase C, casein kinase I, and casein kinase II, with corresponding Ki values of 4.3 μM, 3.8 μM, and 47 in relation to ATP. consist of μM, 80 μM, and 5.1 μM[1].
References	[1]. Naphthalenesulfonamides as calmodulin antagonists and protein kinase inhibitors. Mol Pharmacol. 1986 Jun;29(6):577-81.

Solubility Data

Solubility (In Vitro)

DMSO : ~125 mg/mL (~389.14 mM) H2O : ~50 mg/mL (~155.66 mM)

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.08 mg/mL (6.48 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 20.8 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: ≥ 2.08 mg/mL (6.48 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), clear solution. For example, if 1 mL of working solution is to be prepared, you can add 100 μL of 20.8 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.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	3.1131 mL	15.5657 mL	31.1313 mL
	5 mM	0.6226 mL	3.1131 mL	6.2263 mL
	10 mM	0.3113 mL	1.5566 mL	3.1131 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.