Mustard gas (bis(chloroethyl) thioether) alkylating a DNA amine base.
<b>Vectorization: </b> <a href="//commons.wikimedia.org/wiki/User:Alhadis" title="User:Alhadis">Alhadis</a>
Own work based on: <a href="//commons.wikimedia.org/wiki/File:Mustard-dna.png" title="File:Mustard-dna.png">Mustard-dna.png</a> <i>by</i> <a href="https://en.wikipedia.org/wiki/User:Vuo" class="extiw" title="w:User:Vuo">Vuo</a>