LEQ506 is a second-generation smoothened (smo) inhibitor (antagonist) with IC50s of 2 and 4 nM in humans and mice, respectively.

Physicochemical Properties

Molecular Formula	C25H32N6O
Molecular Weight	432.56
Exact Mass	432.264
CAS #	1204975-42-7
PubChem CID	45100669
Appearance	White to yellow solid powder
LogP	3.546
Hydrogen Bond Donor Count	1
Hydrogen Bond Acceptor Count	7
Rotatable Bond Count	5
Heavy Atom Count	32
Complexity	597
Defined Atom Stereocenter Count	1
SMILES	C[C@@H]1CN(CCN1C2=NC=C(N=C2)C(C)(C)O)C3=NN=C(C(=C3C)C)CC4=CC=CC=C4
InChi Key	POERAARDVFVDLO-QGZVFWFLSA-N
InChi Code	InChI=1S/C25H32N6O/c1-17-16-30(11-12-31(17)23-15-26-22(14-27-23)25(4,5)32)24-19(3)18(2)21(28-29-24)13-20-9-7-6-8-10-20/h6-10,14-15,17,32H,11-13,16H2,1-5H3/t17-/m1/s1
Chemical Name	2-[5-[(2R)-4-(6-benzyl-4,5-dimethylpyridazin-3-yl)-2-methylpiperazin-1-yl]pyrazin-2-yl]propan-2-ol
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	IC50: 2 nM (human smo), 4 nM (mouse smo)[1]
ln Vitro	LEQ506, a smoothened (Smo) inhibitor of the second generation, with IC50 values of 2 nM in humans and 4 nM in mice. The quantity of Gli mRNA in a human cell line (HEPM) indicates that LEQ506 inhibits Hedgehog (Hh) signaling, with an IC50 that is approximately 6-fold lower than that of Compound 2[1]. LEQ506 consistently reduces Gli1 mRNA by approximately 70–80%, making it an effective chemical. LEQ506 (at 1%), an effective drug with an inhibition of 80 to 90% for Gli1 and 60 to 70% for Ptch1, also has a tendency to preferentially inhibit Gli1 mRNA rather than Ptch1 mRNA[2].
References	[1]. Discovery of NVP-LEQ506, a second-generation inhibitor of smoothened. ChemMedChem. 2013 Aug;8(8):1261-5. [2]. Pharmacological evaluation of a series of smoothened antagonists in signaling pathways and after topical application in a depilated mouse model. Pharmacol Res Perspect. 2016 Mar 4;4(2):e00214.
Additional Infomation	LEQ506 has been used in trials studying the treatment of Advanced Solid Tumors, Recurrent or Refractory Medulloblastoma, and Locally Advanced or Metastatic Basal Cell Carcinoma. Smoothened Antagonist LEQ506 is an orally bioavailable small-molecule Smoothened (Smo) antagonist with potential antineoplastic activity. Smoothened antagonist LEQ506 selectively binds to the Hedgehog (Hh)-ligand cell surface receptor Smo, which may result in the suppression of the Hh signaling pathway, thereby inhibiting tumor cell growth. The Hh signaling pathway plays an important role in cellular growth, differentiation and repair. Dysregulated activation of Hh pathway signaling and uncontrolled cellular proliferation, as is observed in a variety of cancers, may be associated with mutations in the Hh-ligand cell surface receptor Smo.

Solubility Data

Solubility (In Vitro)

DMSO: ≥ 100 mg/mL (231.18 mM)

Solubility (In Vivo)

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples. Injection Formulations (e.g. IP/IV/IM/SC) Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline) *Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution. Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline) Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil) Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals). Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)] *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. Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline) Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline) Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline) Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil) Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline) Oral Formulations Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium) Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals). Oral Formulation 3: Dissolved in PEG400 Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose Oral Formulation 6: Mixing with food powders Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.  (Please use freshly prepared in vivo formulations for optimal results.)

Preparing Stock Solutions		1 mg	5 mg	10 mg
	1 mM	2.3118 mL	11.5591 mL	23.1182 mL
	5 mM	0.4624 mL	2.3118 mL	4.6236 mL
	10 mM	0.2312 mL	1.1559 mL	2.3118 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.