Synthesis of purines and their derivatives from HCN.
<a href="//commons.wikimedia.org/wiki/User:%D0%94.%D0%98%D0%BB%D1%8C%D0%B8%D0%BD" title="User:Д.Ильин">Д.Ильин</a>: vectorization, translation
<a href="//commons.wikimedia.org/wiki/File:Basicpurines.png" title="File:Basicpurines.png">File:Basicpurines.png</a> by <a href="https://en.wikipedia.org/wiki/User:Andervik" class="extiw" title="wikipedia:User:Andervik">Andervik</a> at <a href="https://en.wikipedia.org/wiki/" class="extiw" title="wikipedia:">English Wikipedia</a>