STING agonist-17 (compound 4a) is a potent STING agonist/activator with IC50 of 0.062 nM. It has anti-cancer activity and can be used for tumor immunity.

Physicochemical Properties

CAS #	2816929-47-0
Appearance	Off-white to light yellow solid powder
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=0.062 nM
ln Vitro	The activity of four major CYP isozymes (CYP1A2, CYP2C9, CYP2C19, and CYP2D6) with IC50 values > 100 μM and CYP3A4 with an IC50 = 4.2 μM is inhibited by STING agonist-17 (compound 4a)[1]. With an EC50 of 2.0 nM, STING agonist-17 (compound 4a) (0-2 μM, 24 hours) stimulates IFN-β secretion[1]. Compound 4a, or STING agonist-17, has the ability to promote the expression of signal transduction factors at 2 nM, 10 nM, and 6 hours [1]. Compound 4a's pharmacokinetic characteristics in vitro[1]. Compound 4a's parameter values are as follows: 1A2 >100.0, 2C9 >100.0, 2C19 >100.0, 2D6 >100.0, and 3A4 4.2 Cardiotoxicity (IC50, μM) hERG patch clamp assay >50.0, Liver microsomal phase I stability mouse (%) 38.7 ± 2.6 human (%) 11.2 ± 2.7 Plasma stability mouse (%) >99 human (%) >99
ln Vivo	In female BALB/c mice with colon cancer originating from CT26 cells, STING agonist-17 (compound 4a) (intravenous injection; 0.015 mg/kg, 1.5 mg/kg; every other day; a week) inhibits the formation of tumors[1]. Compound 4a's pharmacokinetic characteristics in vivo[1]. AUClast (μg •h/mL) 4.20 ± 0.26 AUC∞ (μg·h/mL) >4.78 ± 0.59 Parameter Compound 4a T1/2 (h) 10.54 ± 4.10 Vss (L/kg) >17.74 ± 5.29 CL (L/h/kg) 2.12 ± 0.27
Cell Assay	Western Blot Analysis[1] Cell Types: THP-1 dual cells Tested Concentrations: 2 nM, 10 nM Incubation Duration: 6 hrs (hours) Experimental Results: Induced phosphorylation of signal transduction factors STING, TBK1, IRF3 and STAT1 at 2 nM. Activated the expression of IFNB gene and IFN stimulated gene (ISG).
Animal Protocol	Animal/Disease Models: Female balb/c (Bagg ALBino) mouse aged 6 weeks[1] Doses: 0.015 mg/kg, 1.5 mg/kg Route of Administration: intravenous (iv) injection ; every other day; a week Experimental Results: Inhibited tumor growth in both doses and caused 57% inhibition at a concentration of 1.5 mg/kg on the 17th day without weight loss.
References	[1]. Development of Potent Immune Modulators Targeting Stimulator of Interferon Genes Receptor. J Med Chem. 2022 Apr 14;65(7):5407-5432.

Solubility Data

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.)