Tofacitinib

Tofacitinib is a pivotal pharmaceutical intermediate and certified reference standard in the industrial synthesis and quality control of this first-in-class JAK inhibitor. The pyrrolopyrimidine core of Tofacitinib is synthesized through coupling of 4-chloro-7H-pyrrolo[2,3-d]pyrimidine with (3R,4R)-N-benzyl-3-methylamino-4-methylpiperidine, followed by deprotection and cyanoacetylation. In quality control contexts, Tofacitinib and its related impurities—including (3S,4R)-Tofacitinib, Tofacitinib Impurity 3 (CAS 1616761-00-2), and various process-related byproducts—are essential analytical reference standards for impurity profiling, analytical method development, and quality control testing. As the first JAK inhibitor approved for autoimmune conditions, Tofacitinib represents a significant therapeutic advance for patients with rheumatoid arthritis and other immune-mediated diseases. The pyrrolopyrimidine scaffold of Tofacitinib serves as a versatile platform for JAK inhibitor development, making Tofacitinib indispensable for pharmaceutical manufacturers developing generic versions and for analytical laboratories performing quality control testing.

 

 Product Parameters

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Parameter	Specification
Product Name	Tofacitinib
CAS Number	477600-75-2
Molecular Formula	C₁₆H₂₀N₆O
Molecular Weight	312.38 g/mol
Density	1.3 g/cm³
pKa	6.04±0.60 (Predicted)
Appearance	Off-white light powder
Storage Condition	–20°C

Application

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Tofacitinib is indicated for adult patients with moderate to severe active rheumatoid arthritis (RA) who have inadequate response to or are intolerant of methotrexate, and may be used in combination with methotrexate or other non-biological disease-modifying antirheumatic drugs (DMARDs).

 

Bioactivity

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Tofacitinib (CP-690550, Tasocitinib) is a novel JAK3 inhibitor with an IC50 of 1 nM, exhibiting 20 to 100-fold lower selectivity against JAK2 compared to JAK1.

 

In Vitro Study

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CP-690550 is a specific oral JAK3 inhibitor that targets both JAK2 and JAK1, with efficacy 20-fold and 100-fold lower than their respective counterparts. CP-690550 exhibits no activity against 30 other kinases, with an average IC50> 3000 nM. It demonstrates 30-fold stronger inhibitory effect on IL-2-induced proliferation compared to GM-CSF-induced proliferation. CP-690550 efficiently suppresses the murine mixed lymphocyte reaction (MLR) (IC50 = 91 nM). When administered to mouse B cells, CP-690550 effectively inhibits IL-4-induced upregulation of CD23 expression (IC50 = 57 nM) and class II major histocompatibility complex (MHC-II) expression (IC50 = 71 nM). Recent studies indicate that low-dose CP-690550 accelerates the development of experimental autoimmune encephalomyelitis by promoting Th17 differentiation.

 

Contact Us

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Whether you're developing a generic JAK inhibitor, validating analytical methods for Tofacitinib, or preparing an ANDA submission, Cosperpharm is your trusted partner for high-quality reference standards and pharmaceutical intermediates. Get in touch to discuss your requirements.