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.
There was a great talk by Jon Baell yesterday, in which he described molecules now referred to as PAINS, or pan-assay interfering compounds (http://pubs.acs.org/doi/pdf/10.1021/jm901137j). 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.
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.