Cletoquine oxalate (Desethylhydroxychloroquine oxalate) is the main active metabolite of Hydroxychloroquine and is formed in the liver from CYP2D6, CYP3A4, CYP3A5 and CYP2C8 isoenzymes. Cletoquine oxalate is also a Chloroquine analogue with activity against Chikungunya virus (CHIKV). Cletoquine oxalate has antimalarial effects and may be utilized in study/research of autoimmune diseases.

Physicochemical Properties

Molecular Formula	C16H22N3OCL.C2H2O4
Molecular Weight	397.85326
Exact Mass	397.14
CAS #	14142-64-4
Related CAS #	Cletoquine;4298-15-1;Cletoquine-d4;1854126-47-8
PubChem CID	46781036
Appearance	Light yellow to yellow solid powder
LogP	2.67
Hydrogen Bond Donor Count	5
Hydrogen Bond Acceptor Count	8
Rotatable Bond Count	9
Heavy Atom Count	27
Complexity	364
Defined Atom Stereocenter Count	0
InChi Key	DTVGVTDECKJJJK-UHFFFAOYSA-N
InChi Code	InChI=1S/C16H22ClN3O.C2H2O4/c1-12(3-2-7-18-9-10-21)20-15-6-8-19-16-11-13(17)4-5-14(15)16;3-1(4)2(5)6/h4-6,8,11-12,18,21H,2-3,7,9-10H2,1H3,(H,19,20);(H,3,4)(H,5,6)
Chemical Name	2-[4-[(7-chloroquinolin-4-yl)amino]pentylamino]ethanol;oxalic acid
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 Vivo

In order to measure the amount of chlorotoquine (desethylhydroxychloroquine) in the blood and tissues of BALB/c mice, hydroxychloroquine (5 mg/kg) was intravenously given. It can be inferred that tissues collect chlorotoquine when the tissue to blood concentration ratio (Kp) is less than 1. Liver (114.3), kidney (24.4), spleen (19.3), lung (16.5), heart (5.5) are the tissues with the highest and lowest chlorotoquine Kp ratios, respectively [3].

References

[1]. Molecular docking studies of chloroquine and its derivatives against P23pro-zbd domain of chikungunya virus: Implication in designing of novel therapeutic strategies. J Cell Biochem. 2019 Oct;120(10):18298-18308. [2]. Development of a novel ion-pairing HPLC-FL method for the separation and quantification of hydroxychloroquine and its metabolites in whole blood. Biomed Chromatogr. 2018 Aug;32(8):e4258. [3]. Simultaneous quantitation of hydroxychloroquine and its metabolites in mouse blood and tissues using LC-ESI-MS/MS: An application for pharmacokinetic studies. J Chromatogr B Analyt Technol Biomed Life Sci. 2018 Jan 1;1072:320-327.

Solubility Data

Solubility (In Vitro)

DMSO : ~5 mg/mL (~12.57 mM)

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 1.67 mg/mL (4.20 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 16.7 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 2: ≥ 1.67 mg/mL (4.20 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 16.7 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	2.5135 mL	12.5676 mL	25.1351 mL
	5 mM	0.5027 mL	2.5135 mL	5.0270 mL
	10 mM	0.2514 mL	1.2568 mL	2.5135 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.