| Field | Specification |
|---|---|
| Target | |
| CAS no. | |
| Applications | |
| Molecular weight | |
| Molecular formula | C48H54Cl2N10O2S2 |
| Purity | |
| SMILES | |
| Form | Solid |
| Storage | |
| Shipping | |
| Catalog no. (Mfr.) | |
| Main SKU |
Compound Overview
MS645 is a bivalent inhibitor of BET bromodomains (BrD), with a Ki of 18.4 nM for BRD4-BD1/BD2. It spatially constrains bivalent inhibition of BRD4 BrDs, resulting in sustained repression of BRD4 transcriptional activity in solid-tumor cells[1]. It is supplied as a light yellow to yellow solid (C48H54Cl2N10O2S2, MW 938.04) at 98.0% purity.
Physical & Chemical Properties
| CAS Number | 2250091-96-2 |
|---|---|
| Molecular Formula | C48H54Cl2N10O2S2 |
| Molecular Weight | 938.04 g/mol |
| Purity | 98.0% |
| Appearance | Solid |
| Color | Light yellow to yellow |
| SMILES | O=C(NCCCCCCCCCCNC(C[C@H]1C2=NN=C(C)N2C3=C(C(C)=C(C)S3)C(C4=CC=C(Cl)C=C4)=N1)=O)C[C@H]5C6=NN=C(C)N6C7=C(C(C)=C(C)S7)C(C8=CC=C(Cl)C=C8)=N5 |
| Target | BRD4(BD1BD2) |
| Signaling Pathway | Epigenetics |
| Solubility | In Vitro: DMSO: 200 mg/mL (213.21 mM; Requires sonication; Hygroscopic DMSO has a significant impact on the solubility of product, please use newly opened DMSO) |
| Storage | -20°C, stored under nitrogen. In solvent: -80°C, 6 months; -20°C, 1 month (stored under nitrogen). |
| Shipping | Room temperature in continental US; may vary elsewhere. |
Biological Activity
IC50 & Target[1]
|
BRD4(BD1BD2) 18.4 nM (Ki) |
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 | 200 mg/mL (213.21 mM) | requires sonication; use freshly opened DMSO (absorbed moisture lowers solubility) |
Aliquot the stock solution and store it at -80°C (up to 6 months) or -20°C (up to 1 month); stored under nitrogen; 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 | ≥ 5 mg/mL (5.33 mM); clear solution |
| How to prepare | Gives a clear solution at ≥ 5 mg/mL (saturation not determined). For 1 mL of working solution: add 100 μL DMSO stock (50.0 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% Corn Oil |
|---|---|
| Result | ≥ 5 mg/mL (5.33 mM); clear solution |
| How to prepare | Gives a clear solution at ≥ 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 (50.0 mg/mL) to 900 μL corn oil. |
Data provided by the manufacturer.
In Vitro
MS645 inhibits cell growth in the noncancer mouse macrophage RAW cell line and nontumorigenic breast epithelial MCF10A cells, with IC50s of 4.1 nM, 6.8 nM, and 7.9 nM for the triple-negative breast cancer (TNBC) cell lines HS5878T, BT549, and MCF 10A[1]. In HCC1806 cells, MS645 (15, 30, 60 nM) markedly reduces c-Myc expression and increases p21, a tumor suppressor and cell-cycle inhibitor[1].
Data provided by the manufacturer. Numbered citations refer to the Literature Cited list in the product description.
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Regulation of inflammatory responses by pH-dependent transcriptional condensates. Cell 2025 Oct 2;188(20):5632-5652.e25. PMID: 40680734
