| Field | Specification |
|---|---|
| Target | |
| Alternative names | LY2523355 |
| CAS no. | |
| Applications | |
| Molecular weight | |
| Molecular formula | C23H37N5O4S2 |
| Purity | |
| SMILES | |
| Form | Solid |
| Storage | |
| Shipping | |
| Catalog no. (Mfr.) | |
| Main SKU |
Compound Overview
Litronesib, also known as LY2523355, is a selective inhibitor of the mitosis-specific kinesin Eg5 and has shown antitumor activity[1]. It is supplied as a white to off-white solid (C23H37N5O4S2, MW 511.70) at 98.84% purity.
Physical & Chemical Properties
| CAS Number | 910634-41-2 |
|---|---|
| Molecular Formula | C23H37N5O4S2 |
| Molecular Weight | 511.70 g/mol |
| Purity | 98.84% |
| Appearance | Solid |
| Color | White to off-white |
| SMILES | CC(C)(C)C(N1[C@@](C2=CC=CC=C2)(CNS(CCNCC)(=O)=O)SC(NC(C(C)(C)C)=O)=N1)=O |
| Target | Eg5 |
| Signaling Pathway | Cell Cycle/DNA Damage; Cytoskeleton |
| Solubility | In Vitro: DMSO: ≥ 50 mg/mL (97.71 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, 2 years; -20°C, 1 year. |
| Shipping | Room temperature in continental US; may vary elsewhere. |
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 (97.71 mM) | use freshly opened DMSO (absorbed moisture lowers solubility) |
Aliquot the stock solution and store it at -80°C (up to 2 years) or -20°C (up to 1 year); 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 (4.89 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 (4.89 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 (4.89 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
Litronesib (LY2523355) acts as a selective inhibitor of Eg5. At 25 nM, Litronesib drives cancer cells to death during mitotic arrest, which requires sustained activation of the spindle-assembly checkpoint (SAC)[1].
In Vivo
In Colo205 xenograft tumors, Litronesib (LY2523355) given i.v. at 1.1, 3.3, 10, and 30 mg/kg shows antitumor activity in a dose-dependent manner and dramatically increases the number of cancer cells immuno-positive for histone H3 phosphorylation[1].
Data provided by the manufacturer. Numbered citations refer to the Literature Cited list in the product description.
Cell Assay[1]
Plate cancer cells in poly-d-lysine coated 96-well plates and incubate overnight. Treat the cells with the indicated concentrations of Litronesib for various time periods. Fix cells with 3.7% formaldehyde in PBS for 45 minutes or with 1× Prefer fixative solution for 30 minutes at room temperature, then permeabilize with cold methanol for 10 minutes followed by 0.2% Triton X-100 in PBS for 10 minutes. Wash the cells three times with PBS. Incubate the cells for 1 hour with 100 μg/mL DNase-free RNase and 10 μg/mL of propidium iodide, and scan for mitotic index (MI) measurement based on DNA condensation, expressed as percentage of cells with condensed DNA. For MI measurement based on histone H3 phosphorylation, or for apoptosis analysis, incubate cells overnight at 4°C with anti-phospho-histone H3 antibody or anti-phospho-histone H2AX, respectively, at 1:1,000 dilution with 5% bovine serum albumin (BSA) in PBS. Wash the cells three times with 0.2% Triton-X 100 in PBS and incubate for 60 minutes at room temperature with Alexa 488 secondary antibody (1:1,000 in PBS-2% BSA). Wash the cells three times again with PBS and stain with 10 μg/mL propidium iodide and 100 μg/mL RNaseA in PBS for 15 minutes. Scan the stained cells with an Acumen Explorer eX3 microplate cytometer. Express the results as percentage of cells positive for phospho-histone H3-Ser10 or phospho-histone H2AX[1].
Animal Administration[1]
Establish and maintain primary human-tumor xenograft models in nude mice. Evaluate antitumor efficacy in subcutaneous xenograft tumor-bearing mice (10 mice per treatment group), derived from either established cancer cell lines or fragments of human tumor explants, as tumor volume from serial caliper measurements, and calculate the volume. Develop the p388 syngeneic tumor model using female BDF1 mice, weighing 20 to 23 g, for high-content imaging analysis; acclimate the mice in-house for one week before use in experiments. Authenticate p388 murine lymphocytic leukemia cells by STR assay and maintain in RPMI1640 medium containing 10% FBS. For inoculation, wash the cells three times with serum-free medium and implant 1.25 million cells into mice by intraperitoneal injection. On day 5 after implantation, treat mice with Litronesib by either intravenous bolus or intravenous infusion at appropriate doses and durations. Euthanize mice, draw the ascitic (intraperitoneal) fluid containing the p388 tumor cells, and analyze phospho-histone H3, G2-M, and apoptosis in it by acumen, flow cytometry, and TUNEL assays. For the pharmacokinetic study, collect blood samples via cardiac puncture, generate plasma with EDTA, and determine Litronesib exposure in the plasma[1].
Data provided by the manufacturer. Numbered citations refer to the Literature Cited list in the product description.
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Kinesins regulate the heterogeneity in centrosome clustering after whole-genome duplication. Life Sci Alliance 2024 Jul 29;7(10):e202402670. PMID: 39074902
Targeting Eg5 using Arry520 combats gastric cancer by inducing monopolar spindles. Gene 2025 Jul 5:955:149458. PMID: 40187619
