<?xml version="1.0" encoding="UTF-8" standalone="yes"?><oembed><version><![CDATA[1.0]]></version><provider_name><![CDATA[amphoteros]]></provider_name><provider_url><![CDATA[http://amphoteros.com]]></provider_url><author_name><![CDATA[ayudin2013]]></author_name><author_url><![CDATA[https://amphoteros.com/author/ayudin2013/]]></author_url><title><![CDATA[Some gems from&nbsp;Colorado]]></title><type><![CDATA[link]]></type><html><![CDATA[<p>I am in Copper Mountain, Colorado, attending the annual meeting of the American Society of Pharmacognosy. Scott Lokey has put together a nice symposium on macrocycles, but a lot here is a bit beyond my expertise. The vast majority of researchers at this meeting are natural products isolation people, a crowd with its own jargon, rules, and ideas about what is cool and what is not.</p>
<p>There was a great talk by Jon Baell yesterday, in which he described molecules now referred to as PAINS, or pan-assay interfering compounds (<a href="http://pubs.acs.org/doi/pdf/10.1021/jm901137j" rel="nofollow">http://pubs.acs.org/doi/pdf/10.1021/jm901137j</a>). Essentially, anything that is an electrophile or a masked electrophile, is sure to cause trouble in assays. Looking out for structures that contain PAINS is not that tough if you are a trained chemist.</p>
<p>There were some real gems in the total synthesis section. I particularly liked the talk by Bill Maio of New Mexico State University. As someone who has been interested in new ways of making macrocycles, I really enjoyed his unconventional approach to making the amide bond of taumycin A. The allene intermediate shown below is generated by the base-induced decomposition of the corresponding beta-ketoester. I found this way of closing the ring to be very creative.</p>
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<p style="text-align:center;"><a href="http://pubs.acs.org/doi/abs/10.1021/ol5025585" rel="nofollow">http://pubs.acs.org/doi/abs/10.1021/ol5025585</a></p>
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