Alloxan
<a href="//commons.wikimedia.org/wiki/User:Geralt_Riv" title="User:Geralt Riv">Geralt Riv</a>
2018-01-28
Own work based on: <a href="//commons.wikimedia.org/wiki/File:Alloxan.png" title="File:Alloxan.png">Alloxan.png</a>