*The following content is generated by AI and is for reference only.
<h3>Overview</h3>
<p>Tofacitinib Impurity 19 is a critical synthetic intermediate and degradation product associated with the JAK inhibitor Tofacitinib. It is primarily generated during <strong>pharmaceutical synthesis</strong> or stress testing. The compound features the molecular formula C<sub>20</sub>H<sub>26</sub>N<sub>4</sub>O<sub>3</sub> (CAS No. 159789-48-5), serving as a key reference standard for <strong>quality control</strong> in API manufacturing.</p>
<h3>Application</h3>
<ul>
<li><strong>R&D Validation:</strong> Used to establish HPLC methods for detecting trace impurities in drug substances.</li>
<li><strong>Regulatory Compliance:</strong> Essential for ICH Q3B guidelines regarding impurity qualification in new drug applications.</li>
<li><strong>Stability Studies:</strong> Monitored to assess long-term storage stability of Tofacitinib formulations under various conditions.</li>
</ul>
<h3>Precautions</h3>
<p>Strictly store at -20°C in a desiccated environment away from light. Handle only within certified fume hoods using appropriate PPE due to potential mutagenicity. Do not use in human clinical trials without specific regulatory approval for reference standards.</p>