WF-47-JS03 is a potent and specific RET kinase inhibitor (antagonist) with over 500-fold selectivity over the kinase insert domain receptor (KDR). WF-47-JS03 acts on Ba/F3 cells transfected with KIF5B-RET and LC-2/ad lung cancer cells transfected with CCDC6-RET, with IC50 of 1.7 nM and 5.3 nM respectively. Can penetrate the BBB (blood-brain barrier).

Physicochemical Properties

Molecular Formula	C30H38N6O2
Molecular Weight	514.661726474762
Exact Mass	514.305
CAS #	2561413-77-0
PubChem CID	145996543
Appearance	White to off-white solid powder
LogP	5.3
Hydrogen Bond Donor Count	2
Hydrogen Bond Acceptor Count	7
Rotatable Bond Count	6
Heavy Atom Count	38
Complexity	771
Defined Atom Stereocenter Count	0
InChi Key	YRBWLEAMGAGYBK-UHFFFAOYSA-N
InChi Code	InChI=1S/C30H38N6O2/c1-29(2)16-21(17-30(3,4)35(29)5)33-27-25(19-11-9-8-10-12-19)26(31)36-28(34-27)22(18-32-36)20-13-14-23(37-6)24(15-20)38-7/h8-15,18,21H,16-17,31H2,1-7H3,(H,33,34)
Chemical Name	3-(3,4-dimethoxyphenyl)-5-N-(1,2,2,6,6-pentamethylpiperidin-4-yl)-6-phenylpyrazolo[1,5-a]pyrimidine-5,7-diamine
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	With IC50s of 0.99 and 1.5 μM, respectively, WF-47-JS03 inhibits Tel-KDR transfected Ba/F3 cells as well as Ba/F3 wild-type cell lines[1].
ln Vivo	WF-47-JS03 significantly inhibits tumor growth in RIE KIF5B-RET xenograft mice and is well tolerated at 1, 3, and 10 mg/kg in the 10 day study[1].
Animal Protocol	Animal/Disease Models: Female 6-8 week old Harlan Foxn1 nude mice with RIE-RET-KIF5B transgenic cell line Doses: 1, 3, 10 mg/kg Route of Administration: Dosed orally, 1x daily for 10 days Experimental Results: Inhibited tumor growth in RIE KIF5B-RET xenograft mice.
References	[1]. Efficacy and Tolerability of Pyrazolo[1,5- a]pyrimidine RET Kinase Inhibitors for the Treatment of Lung Adenocarcinoma. ACS Med Chem Lett. 2020 Feb 12;11(4):558-565.

Solubility Data

Solubility (In Vitro)

DMSO: 62.5 mg/mL (121.44 mM)

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.08 mg/mL (4.04 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 (4.04 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	1.9430 mL	9.7152 mL	19.4303 mL
	5 mM	0.3886 mL	1.9430 mL	3.8861 mL
	10 mM	0.1943 mL	0.9715 mL	1.9430 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.