4,4'-MDA (precursor for MDI and polyurethanes)
<a href="//commons.wikimedia.org/wiki/User:Marmelad" title="User:Marmelad">Marmelad</a>
2008-09-02
based on <a href="//commons.wikimedia.org/wiki/File:4,4%27-diaminodifenylmethaan.png" title="File:4,4'-diaminodifenylmethaan.png">Image:4,4'-diaminodifenylmethaan.png</a> by <a href="//commons.wikimedia.org/w/index.php?title=User:Klever&amp;action=edit&amp;redlink=1" class="new" title="User:Klever (page does not exist)">Klever</a>