Todralazine HCl (Ecarazine HCl) is an anti-hypertensive (blood pressure lowering) agent, a β2 adrenergic receptor (β2AR) blocker, and has antioxidant and free radical scavenging activities.

Physicochemical Properties

Molecular Formula	C11H13CLN4O2
Molecular Weight	268.69952
Exact Mass	268.073
Elemental Analysis	C, 49.17; H, 4.88; Cl, 13.19; N, 20.85; O, 11.91
CAS #	3778-76-5
Related CAS #	Todralazine; 14679-73-3
PubChem CID	19604
Appearance	White to off-white solid powder
Density	1.328g/cm3
LogP	2.968
Hydrogen Bond Donor Count	3
Hydrogen Bond Acceptor Count	5
Rotatable Bond Count	4
Heavy Atom Count	18
Complexity	262
Defined Atom Stereocenter Count	0
SMILES	Cl.CCOC(NNC1=NN=CC2=CC=CC=C12)=O
InChi Key	OMCOKCNIYWULQH-UHFFFAOYSA-N
InChi Code	InChI=1S/C11H12N4O2.ClH/c1-2-17-11(16)15-14-10-9-6-4-3-5-8(9)7-12-13-10;/h3-7H,2H2,1H3,(H,13,14)(H,15,16);1H
Chemical Name	ethyl N-(phthalazin-1-ylamino)carbamate;hydrochloride
Synonyms	Todralazine hydrochloride; Todralazine HCl
HS Tariff Code	2934.99.03.00
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

Targets	β2AR
References	[1]. Todralazine protects zebrafish from lethal effects of ionizing radiation: role of hematopoietic cell expansion. Zebrafish. 2015 Feb;12(1):33-47.
Additional Infomation	An antihypertensive agent with both central and peripheral action; it has some central nervous system depressant effects. See also: Todralazine (annotation moved to).

Solubility Data

Solubility (In Vitro)

DMSO: ~125 mg/mL (~465.2 mM) H2O: ~14.29 mg/mL (~53.2 mM)

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.08 mg/mL (7.74 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 (7.74 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. Solubility in Formulation 3: ≥ 2.08 mg/mL (7.74 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 20.8 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	3.7216 mL	18.6081 mL	37.2162 mL
	5 mM	0.7443 mL	3.7216 mL	7.4432 mL
	10 mM	0.3722 mL	1.8608 mL	3.7216 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.