« Roche Closes Nutley, Once Its US R&D Home |
| Shire's Replagal Problems: An Inside Look? »
June 27, 2012
Bungled Structure, And How
A lot of natural product structures have been misassigned over the years. In the old days, it was a wonder when you were able to assign a complex one at all. Structure determination, pre-NMR, could be an intellectual challenge at the highest level, something like trying to reconstruct a position on a chess board in the dark, based on acrostic clues in a language you don't speak. The advent of modern spectroscopy turned on the lights, which is definitely a good thing, but many people who'd made their careers under the old system missed the thrill of the old hunt when it was gone.
But even now, it's possible to get structures wrong - even with high-field 2-D NMR, even with X-ray spectroscopy. Natural products can be startlingly weird by the standards of human chemistry, and I still have a lot of sympathy for anyone who's figuring them out. My sympathy goes only so far, though.
Specifically, this case. I have to agree with the BRSM Blog, which says: "I have to say that I think I could have done a better job myself. Drunk." Think that's harsh? Check out the structures. The proposed structure had two napthalenes, with two methoxys and four phenols. But the real natural product, as it turns out, has one methoxy and one phenol. And no napthyls. And four flipping bromine atoms. Why the vengeful spirit of R. B. Woodward hasn't appeared, shooting lightning bolts and breaking Scotch bottles over people's heads, I just can't figure.
+ TrackBacks (0) | Category: Analytical Chemistry | Chemical News | Natural Products
POST A COMMENT