Tolebrutinib (SAR442168) is a potent, selective, orally bioactive and BBB (blood-brain barrier) permeable/penetrable inhibitor of Bruton's tyrosine kinase (BTK) in Ramos B cells and HMC microglia. IC50s are 0.4 and 0.7 nM respectively. Tolebrutinib has efficacy in central nervous system immunity. Tolebrutinib may be used in multiple sclerosis (MS) research.

Physicochemical Properties

Molecular Formula	C26H25N5O3
Molecular Weight	455.5084
Exact Mass	455.195
CAS #	1971920-73-6
PubChem CID	124111565
Appearance	Off-white to light yellow solid powder
Density	1.3±0.1 g/cm3
Boiling Point	644.4±65.0 °C at 760 mmHg
Flash Point	343.5±34.3 °C
Vapour Pressure	0.0±1.9 mmHg at 25°C
Index of Refraction	1.680
LogP	1.76
Hydrogen Bond Donor Count	1
Hydrogen Bond Acceptor Count	5
Rotatable Bond Count	5
Heavy Atom Count	34
Complexity	749
Defined Atom Stereocenter Count	1
SMILES	C=CC(=O)N1CCC[C@H](C1)N2C3=C(C(=NC=C3)N)N(C2=O)C4=CC=C(C=C4)OC5=CC=CC=C5
InChi Key	KOEUOFPEZFUWRF-LJQANCHMSA-N
InChi Code	InChI=1S/C26H25N5O3/c1-2-23(32)29-16-6-7-19(17-29)30-22-14-15-28-25(27)24(22)31(26(30)33)18-10-12-21(13-11-18)34-20-8-4-3-5-9-20/h2-5,8-15,19H,1,6-7,16-17H2,(H2,27,28)/t19-/m1/s1
Chemical Name	4-amino-3-(4-phenoxyphenyl)-1-[(3R)-1-prop-2-enoylpiperidin-3-yl]imidazo[4,5-c]pyridin-2-one
Synonyms	Tolebrutinib; 1971920-73-6; PRN2246; SAR442168; Tolebrutinib [INN];
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

Targets	BTK (IC50 = 0.7 nM)
ln Vitro	PRN2246 inhibits both Fc receptor activation (IC50=166 and 9.6 nM for FcεR and FcγR) and BCR-mediated immune cell activation (IC50=10 nM) [2]. With an IC50 of 157 nM, PRN2246 targets small molecule FcγR activation via persistent port BTK [2].
ln Vivo	PRN2246 (1-5 mg/kg; po, qd, for 28 days) exhibits dose-induced protection in myelin oligodendrocyte glycoprotein (MOG)-induced experimental autoimmune encephalitis (EAE) model [2].
References	[1]. Radiosynthesis of a Bruton's tyrosine kinase inhibitor, [ 11 C]Tolebrutinib, via palladium-NiXantphos-mediated carbonylation. J Labelled Comp Radiopharm. 2020 Sep;63(11):482-487. [2]. PRN2246, a potent and selective blood brain barrier penetrating BTK inhibitor, exhibits efficacy in central nervous system immunity. Multiple Sclerosis Journal. 2017;Poster Session 2:P989.
Additional Infomation	Tolebrutinib is an orally bioavailable, brain-penetrant, selective, small molecule inhibitor of Bruton's tyrosine kinase (BTK), with potential immunomodulatory and anti-inflammatory activities. Upon oral administration, tolebrutinib is able to cross the blood-brain barrier and inhibits the activity of BTK both peripherally and in the central nervous system (CNS). This prevents the activation of the B-cell antigen receptor (BCR) signaling pathway, and the resulting immune activation and inflammation. The inhibition of BTK activity also prevents microglial inflammatory signaling in the CNS, and the resulting immune activation, neuroinflammation and neurodegeneration. BTK, a cytoplasmic tyrosine kinase and member of the Tec family of kinases, plays an important role in B lymphocyte development, activation, signaling, proliferation and survival. In addition to B cells, BTK is also expressed in innate immune cells, including macrophages and microglia, and plays an important role in the regulation of microglial inflammatory signaling.

Solubility Data

Solubility (In Vitro)

DMSO : ~100 mg/mL (~219.53 mM)

Solubility (In Vivo)

Solubility in Formulation 1: ≥ 2.5 mg/mL (5.49 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 (5.49 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 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 (5.49 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	2.1953 mL	10.9767 mL	21.9534 mL
	5 mM	0.4391 mL	2.1953 mL	4.3907 mL
	10 mM	0.2195 mL	1.0977 mL	2.1953 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.