*The following content is generated by AI and is for reference only.
<h3>Overview</h3>
<p><strong>4-chloro-1H-pyrazolo[3,4-d]pyrimidine</strong> (CAS: 26097-75-6) is a key heterocyclic intermediate with formula C<sub>5</sub>H<sub>3</sub>ClN<sub>4</sub>. It is synthesized via chlorination of pyrazolopyrimidine derivatives using phosphorus oxychloride. This compound serves as a fundamental scaffold for pharmaceutical development.</p>
<h3>Application</h3>
<ul>
<li>Pharmaceutical synthesis: Precursor for kinase inhibitors and antiviral agents.</li>
<li>Agrochemicals: Building block for novel herbicides and fungicides.</li>
<li>Material science: Component in functional organic semiconductors.</li>
</ul>
<h3>Precautions</h3>
<p>Store in sealed containers under inert atmosphere at 2-8°C. Use PPE including nitrile gloves and goggles; avoid inhalation of dust. Not approved for direct clinical use without further derivatization.</p>