| Field | Specification |
|---|---|
| Target | |
| Alternative names | Casein Kinase I Inhibitor |
| CAS no. | |
| Applications | |
| Molecular weight | |
| Molecular formula | C23H18N4O3 |
| Purity | |
| SMILES | |
| Form | Solid |
| Storage | |
| Shipping | |
| Catalog no. (Mfr.) | |
| Main SKU |
Compound Overview
D4476, also known as Casein Kinase I Inhibitor, is a potent, selective, cell-permeable inhibitor of casein kinase 1 (CK1), with an IC50 of 0.3 μM in vitro. It is supplied as a white to yellow solid (C23H18N4O3, MW 398.41) at 99.89% purity.
Physical & Chemical Properties
| CAS Number | 301836-43-1 |
|---|---|
| Molecular Formula | C23H18N4O3 |
| Molecular Weight | 398.41 g/mol |
| Purity | 99.89% |
| Appearance | Solid |
| Color | White to yellow |
| SMILES | O=C(N)C1=CC=C(C=C1)C(N2)=NC(C3=CC=C4OCCOC4=C3)=C2C5=NC=CC=C5 |
| Target | CK1 |
| Signaling Pathway | Cell Cycle/DNA Damage; Stem Cell/Wnt; Autophagy; Apoptosis |
| Solubility | In Vitro: DMSO: ≥ 50 mg/mL (125.50 mM; Hygroscopic DMSO has a significant impact on the solubility of product, please use newly opened DMSO) * "≥" means soluble, but saturation unknown. |
| Storage | Powder: -20°C, 3 years; 4°C, 2 years. In solvent: -80°C, 1 year; -20°C, 6 months. |
| Shipping | Room temperature in continental US; may vary elsewhere. |
Biological Activity
IC50 & Target[1]
|
CK1 0.3 μM (IC50) |
Literature Cited
Sources cited in this description and in the In Vitro & In Vivo Data tab. Peer-reviewed publications that used this product are listed under References.
Safety
For Research Use Only. Not for use in diagnostic or therapeutic procedures, and not for human or veterinary use. Handle in accordance with the Safety Data Sheet and your institution's chemical hygiene plan.
In Vitro
| Solvent | Solubility | Notes |
|---|---|---|
| DMSO | ≥ 50 mg/mL (125.50 mM) | use freshly opened DMSO (absorbed moisture lowers solubility) |
Aliquot the stock solution and store it at -80°C (up to 1 year) or -20°C (up to 6 months); avoid repeated freeze-thaw cycles.
In Vivo
Choose the formulation that suits the animal model and route of administration; percentages are volume ratios of the final working solution. Start from a clear DMSO stock (see In Vitro above), add the co-solvents one at a time in the order listed, mixing after each addition, and prepare the working solution fresh on the day of dosing. If precipitation or phase separation occurs, gentle warming or sonication can help.
Protocol 1
| Composition | 10% DMSO + 40% PEG300 + 5% Tween-80 + 45% saline |
|---|---|
| Result | ≥ 2.5 mg/mL (6.27 mM); clear solution |
| How to prepare | Gives a clear solution at ≥ 2.5 mg/mL (saturation not determined). For 1 mL of working solution: add 100 μL DMSO stock (25.0 mg/mL) to 400 μL PEG300; then 50 μL Tween-80; then 450 μL saline to bring the volume to 1 mL. Saline: dissolve 0.9 g sodium chloride in ddH2O and make up to 100 mL. |
Protocol 2
| Composition | 10% DMSO + 90% (20% SBE-β-CD in saline) |
|---|---|
| Result | ≥ 2.5 mg/mL (6.27 mM); clear solution |
| How to prepare | Gives a clear solution at ≥ 2.5 mg/mL (saturation not determined). For 1 mL of working solution: add 100 μL DMSO stock (25.0 mg/mL) to 900 μL 20% SBE-β-CD in saline. 20% SBE-β-CD in saline: dissolve 2 g SBE-β-CD powder in 10 mL saline until clear (4°C, store up to one week). |
Protocol 3
| Composition | 10% DMSO + 90% Corn Oil |
|---|---|
| Result | ≥ 2.5 mg/mL (6.27 mM); clear solution |
| How to prepare | Gives a clear solution at ≥ 2.5 mg/mL (saturation not determined). Use with caution if continuous dosing will exceed two weeks. For 1 mL of working solution: add 100 μL DMSO stock (25.0 mg/mL) to 900 μL corn oil. |
Data provided by the manufacturer.
In Vitro
D4476 is a potent and fairly selective inhibitor of CK1 in vitro and in cells. In H4IIE hepatoma cells, phosphorylation of the endogenous transcription factor forkhead box O1a (FOXO1a) at Ser322 and Ser325 within its MPD is specifically inhibited by D4476, while other sites are unaffected. In an assay of CK1δ at 0.1 mM ATP with a phosphorylated peptide, TFRPRTSpSNASTIS, covering residues 312–325 of FOXO1a, inhibition occurs with an IC50 value of 0.3 μM. Lowering the ATP concentration progressively decreases the IC50 value for CK1δ, indicating that D4476 acts as an ATP-competitive inhibitor of CK1[1].
Data provided by the manufacturer. Numbered citations refer to the Literature Cited list in the product description.
Cell Assay[2]
Use D4476 for inhibition of Csnk1a1. Add D4476 to leukemia cells held in 96-well plates (5,000 cells per well) in medium containing 10 ng/mL mIL-3. Perform a D4476 dose titration using D4476 at 2.5 μM, 5 μM, 10 μM, 20 μM, and 40 μM in cell cultures at a final DMSO percentage of 0.4%. Likewise, add D4476 to LSK cells grown in SFEM medium containing mTpo and mScf. After 96 h of treatment, count cells by flow cytometry using CountBright absolute counting beads[2].
Data provided by the manufacturer. Numbered citations refer to the Literature Cited list in the product description.
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Inhibition of CK1ε potentiates the therapeutic efficacy of CDK4/6 inhibitor in breast cancer. Nat Commun 2021 Sep 10;12(1):5386. PMID: 34508104
Androgen deprivation upregulates SPINK1 expression and potentiates cellular plasticity in prostate cancer. Nat Commun 2020 Jan 20;11(1):384. PMID: 31959826
Molecular glue degrader function of SPOP enhances STING-dependent immunotherapy efficacy in melanoma models. J Clin Invest 2025 Oct 28:e191772. PMID: 41148213
Nicotinamide improves in vitro lens regeneration in a mouse capsular bag model. Stem Cell Res Ther 2022 May 12;13(1):198. PMID: 35550648
The APC/C adaptor Cdh1 stabilizes STING to potentiate innate immune activation in renal cell carcinoma. Sci Signal 2026 Jun 23;19(943):eaef1474. PMID: 42335217
Casein kinase I isoforms contribute to platelet activation and thrombogenesis via RIPK3-MLKL signaling. Commun Biol 2025 Sep 30;8(1):1384. PMID: 41028907
Casein Kinase 1α as a Novel Factor Affects Thyrotropin Synthesis via PKC/ERK/CREB Signaling. Int J Mol Sci 2023 Apr 11;24(8):7034. PMID: 37108197
CSNK1A1, KDM2A, and LTB4R2 Are New Druggable Vulnerabilities in Lung Cancer. Cancers (Basel) 2021 Jul 12;13(14):3477. PMID: 34298691
Casein kinase 1α regulates testosterone synthesis and testis development in adult mice. Endocrinology 2023 Mar 13;164(5):bqad042. PMID: 36929849
β-catenin stimulates Tcf7l1 degradation through recruitment of casein kinase 2 in mouse embryonic stem cells. Biochem Biophys Res Commun 2020 Apr 2;524(2):280-287.
