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Catalog No. T6101   CAS 1229208-44-9
Synonyms: GS-9973

Entospletinib (GS-9973) (IC50= 7.7 nM)is a specific Syk inhibitor, which is orally bioavailable.

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Entospletinib Chemical Structure
Entospletinib, CAS 1229208-44-9
Pack Size Availability Price/USD Quantity
1 mg In stock $ 32.00
2 mg In stock $ 45.00
5 mg In stock $ 74.00
10 mg In stock $ 98.00
25 mg In stock $ 178.00
50 mg In stock $ 272.00
100 mg In stock $ 438.00
200 mg In stock $ 649.00
1 mL * 10 mM (in DMSO) In stock $ 81.00
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Purity: 99.51%
Purity: 99.05%
Purity: 98.2%
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Biological Description
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Storage & Solubility Information
Description Entospletinib (GS-9973) (IC50= 7.7 nM)is a specific Syk inhibitor, which is orally bioavailable.
Targets&IC50 Syk:IC50: 7.7 nM
In vitro In cells, GS-9973 also displays excellent specificity for Syk, and effectively inhibits BCR-mediated activation and proliferation of B-cells, as well as immune-complex-stimulated cytokine production in monocytes. In Caco-2 cell, GS-9973 exhibits good bidirectional permeability across cell monolayers.
In vivo In rat and dog, GS-9973 (1 mg/kg) by oral administration shows moderate to high bioavailability. In a rat collagen-induced arthritis model, GS-9973 (1-10 mg/kg) by oral administrations significantly suppress ankle inflammation. GS-9973(ED50 =1.2 -3.9 mg/kg) exhibits disease-modifying activity such as pannus formation, cartilage damage, bone resorption, and periosteal bone formation.
Kinase Assay In the determination of full-length baculovirus expressed Syk kinase activity, the reaction system was 25 μL containing 25 mM Tris-HCl, pH 7.5, 5 mM β-glycerophosphate, 2 mM DTT, 0.1 mM Na3VO4, 10 mM MgCl2, 0.5 μM Promega PTK Biotin Peptide Substrate 1, 0.01% casein, 1, 0.01% Triton X-100, 0.25% Glycerol, and 40 mM ATP (Km for ATP). After incubation for 60 minutes at room temperature, the reaction was stopped by adding 30 mM EDTA (30 μL of SA-APC and 4 nM PT-66 antibody). After measuring the plate, the IC50 value of the test compound was calculated using a 4-parameter linear regression algorithm.
Cell Research In MV-4-11 cells, the functional effect of the compound on the cellular Flt3 activity was determined by inhibition of cell proliferation. Cells were diluted in 96 well flat bottom tissue culture plates in RPMI medium containing 10% FBS and compound dilutions were added and incubated at 37°C for 72 hours. Aramazol (10%) was added to the cells and the cells were incubated for another 12-18 hours at 37°C. Finally, the inhibition of the relative cell number was measured at 570/600 nm in the spectrophotometer.
Animal Research In the rat collagen-induced arthritis (CIA) model, Entospletinib (10 mg/kg), which is dissolved in hydrogenated castor oil,ethanol or physiological saline, is taken by oral.
Synonyms GS-9973
Molecular Weight 411.46
Formula C23H21N7O
CAS No. 1229208-44-9


Powder: -20°C for 3 years | In solvent: -80°C for 1 year

Solubility Information

DMSO: 50 mg/mL (121.52 mM)

TargetMolReferences and Literature

1. J Med Chem. 2014, 57(9), 3856-3873. 2. Burke RT, et al. Oncotarget. 2014, 5(4), 908-915.


1. Geng R, Zhao Y, Xu W, et al.SIRPB1 regulates inflammatory factor expression in the glioma microenvironment via SYK: functional and bioinformatics insights.Journal of Translational Medicine.2024, 22(1): 338

Related compound libraries

This product is contained In the following compound libraries:
Drug Repurposing Compound Library FDA-Approved Kinase Inhibitor Library Inhibitor Library Anti-Cancer Approved Drug Library Anti-Cancer Active Compound Library Anti-Cancer Clinical Compound Library Kinase Inhibitor Library Anti-Cancer Drug Library Tyrosine Kinase Inhibitor Library Angiogenesis related Compound Library

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Entospletinib 1229208-44-9 Angiogenesis Tyrosine Kinase/Adaptors Syk inhibit Spleen tyrosine kinase GS-9973 GS 9973 GS9973 Inhibitor inhibitor