Tofacitinib (CP-690550,Tasocitinib)


Technical Data

Molecular Weight 312.37 Storage powder


in solvent
CAS No. 477600-75-2 Synonyms Tasocitinib
Solubility (25°C) * In vitro DMSO 62 mg/mL warmed (198.48 mM)
Water <1 mg/mL
Ethanol <1 mg/mL
In vivo 2% DMSO+30% PEG 300+ddH2O 5mg/mL
* <1 mg/ml means slightly soluble or insoluble.
* Please note that Selleck tests the solubility of all compounds in-house, and the actual solubility may differ slightly from published values. This is normal and is due to slight batch-to-batch variations.
Chemical Name 3-((3R,4R)-4-methyl-3-(methyl(7H-pyrrolo[2,3-d]pyrimidin-4-yl)amino)piperidin-1-yl)-3-oxopropanenitrile

Biological Activity

Description Tofacitinib (CP-690550,Tasocitinib) is a novel inhibitor of JAK3 with IC50 of 1 nM in cell-free assays, 20- to 100-fold less potent against JAK2 and JAK1.
JAK3 [1]
(Cell-free assay)
JAK2 [1]
(Cell-free assay)
JAK1 [1]
(Cell-free assay)
ROCK2 [1]
(Cell-free assay)
LCK [1]
(Cell-free assay)
1 nM 20 nM 112 nM 3.4 μM 3.87 μM
In vitro CP-690550 is a specific, orally inhibitor of JAK3, it is 20- to 100-fold less potent for JAK2 and JAK1 with IC50 of 20 nM and 112 nM, respectively. CP-690550 doesn't have potent activity against 30 other kinases (all median IC50 > 3000 nM). CP-690,550 inhibits IL-2–induced proliferation with 30-fold greater potency than its effects on GM-CSF–induced proliferation. [1] CP-690550 effectively inhibits a murine mixed lymphocyte reaction (MLR) (IC50 = 91 nM). [2] CP-690550 potently inhibits IL-4 induced upregulation of CD23 (IC50=57 nM) and class II major histocompatibility complex (MHCII) expression (IC50=71 nM) on murine B cells. [3] A recent research indicates low dose of CP-690550 accelerates the onset of experimental autoimmune encephalomyelitis by potentiating Th17 differentiation. [4]
In vivo In a murine model of heterotopic heart transplantation (DBA2 donor heart into C57/BL6 host), CP-690550 results in a dose-dependent increase in survival of transplanted hearts.The EC50 (drug concentration in blood at which 50% of mice will maintain their graft for >28 days) to be ~60 ng/mL.CP-690550 prevents rejection of allogeneic kidneys in nonhuman primate (NHPs, macaca fascicularis) (MST of 62 and 83 days for the 50 to 100 ng/ml groups and 200 to 400 ng/ml groups, respectively). [1] Mice chronically dosed with CP-690550 (1.5-15 mg/kg/day) demonstrates dose and time-dependent alterations in lymphocyte subsets when examined by flow cytometry. The most dramatic change observed is a 96% reduction in splenic NK1.1+TCRb-cell numbers following 21 days of treatment. Delayed-type hypersensitivity (DTH) responses in sensitized mice are reduced in a dose-dependent manner following treatment with CP-690550 (1.87–30 mg/kg, s.c.). Extended survival of neonatal Balb/c hearts implanted into the ear pinna of MHC mismatched C3H/HEN mice is observed with CP-690550 monotherapy (10–30 mg/kg/day), but improved upon combination with cyclosporin (10 mg/kg/day). [2]

Protocol (Only for Reference)

Kinase Assay:


JAK3 Kinase Assay A fragment encoding the catalytic domain of human JAK3 (785aa to 1125aa, JH1 catalytic domain) is amplified by PCR from the full length cDNA and cloned into the EcoRI site of the baculovirus transfer vector pVL1393. Recombinant baculovirus is used to infect Sf9 (Spodoptera frugipedra) cells and recombinant GSTJAK3 fusion protein is isolated on glutathione sepharose. The fusion protein is eluted with reduced glutathione and stored in buffer containing 50 mM Tris, pH 7.5, 10 mM DTT and 10% glycerol. JAK3 kinase activity is measured by ELISA as follows: Plates are coated overnight with a random L-glutamic acid and tyrosine co-polymer (4:1) (100 ug/mL). The plates are washed and recombinant JAK3 JH1:GST (100 ng/well) with or without inhibitors is incubated at room temperature for 30 minutes, after which HRP-conjugated PY20 anti-phosphotyrosine antibody (ICN) is added and developed by TMB (3,3',5,5'-tetramethylbenzidine). Other kinases (Table 1) are produced in E. coli or in insect cells, depending upon what is found to be optimal for the given kinase. The catalytic activity of tyrosine kinases is easured using the aftorementioned ELISA, whereas serine/threonine kinases are assayed using radioactive enzyme assays.

Cell Assay:


Cell lines Human T blasts cell
Concentrations 0-4000 nM
Incubation Time 4 days

To measure IL-2-dependent proliferation, isolated lymphocytes are resuspended to a cell density of 1-2 × 106/mL in complete RPMI medium (RPMI 1640 containing 10% (w/v) fetal calf serum (FCS), 1%(w/v) penicillin and treptomycin).Phytohemagluttinin (PHA) is added to a final concentration of 10mg/mL, and the culture incubated for 3 days at 37 °C in a humidified 5% (v/v) CO2 incubator to upregulate IL-2R and JAK3 expression. IL-2 (200U/mL), with or without CP-690,550 is then added and the cells are incubated for 72 hours at 37 °C in a humidified 5% (v/v) CO2 incubator, after which 50 mL of 3H-thymidine (5mCi/mL) is added. The plates are incubated for an additional 18 hours, harvested with a 96-well harvester, and counted on a scintillation counter. HUO3 cells are maintained in culture with granulocyte-macrophage colony stimulating factor and human foreskin fibroblasts are maintained in culture with 10% fetal calf serum. CP-690550 is added to freshly plated cells and cultured for 4 days. 3Hthymidine is added during the last 18 hours of the culture period.

Animal Study:


Animal Models DBA/2 and C57/BL6 mice
Formulation CP-690550 is dissolved in polyethylene glycol 300.
Dosages 0-136 ng/mL
Administration Administered via osmotic minipump infusion


Customer Product Validation

Data from [Data independently produced by Cancer Discov, 2012, 2(7), 591-7]

Effects of CP-690550 on NKTCL cell lines. NK-S1, KHYG-1 cells were treated with CP-690550 for 48 hours, and the effect on STAT5 phosphorylation was evaluated by Western blotting.

Data from [Data independently produced by , , Leukemia, 2016, 30(6):1311-9]

(d) Immunoblots of indicated proteins in primary EITL cells treated with PD0325901, Tofacitinib and Trametinib for two and Stattic for 24 h at indicated concentrations.

Tofacitinib (CP-690550,Tasocitinib) has been referenced in 34 publications.



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Chemical Structure

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