Coenzyme B (CoB), an coenzyme in methanogenesis; 7-mercaptoheptanoylthreonine phosphate
<a href="//commons.wikimedia.org/wiki/User:Yikrazuul" title="User:Yikrazuul">Yikrazuul</a>
<span class="int-own-work" lang="en">Own work</span>; <a href="//commons.wikimedia.org/wiki/Special:BookSources/978-0195122589" title="Special:BookSources/978-0195122589">ISBN 978-0195122589</a>; S. 245