One of the folks over at Chemistry Blog has run into a shortage: he and his labmates have tried to order (-) sparteine from every supplier in the book, and there's none to be had. So if anyone has a big dusty bottle of it sitting around, you might drop these desperate chemists a line. But that got me thinking about the way things suddenly dry up like this.
The situation is different than for an industrial chemical shortage, like the acetonitrile crunch that we went through a while back (and which has long since eased up). It's quite unusual for a bulk chemical like that to go down; several factors hit all at once in that case, and it affected an awful lot of people who needed the solvent. But fine chemicals are much weirder. When you trace some of them back to their real sources, you sometimes find that there are really only a couple of people in the world at any given time making some of these things. Or, in many cases, you find that there's no one making it at all - someone made a bunch a few years ago for some reason, sold the excess to a supplier, and everyone else has been buying it from that same bottle ever since.
So when one of these small-scale itemsevaporates, the reason can be supply: no one makes it any more. Or it can be demand-driven: a single drug company's scale-up group can deplete the world's commercial supply of some strange little molecule when they suddenly switch to a 500-gram run. Everyone working in such a group knows to call all the suppliers when they have a prep calling for some weirdo starting material, and they'll often take the precaution of ordering whatever's out there to be had. (That serves as a cushion while they contract someone else to crank out a batch or figure out how to make it themselves). Naturally, you'd rather have your drug candidates depend only on things that can be ordered in tank car lots, but that's just not always possible.
So it could be that someone needed a lot of (-) sparteine for an asymmetric synthesis recently, and bought up the existing world stocks. But this one sounds like more of a supply problem. There would appear to be customers out there, who have been draining the existing stocks, but no one's been able to replenish them. TCI apparently stated that it's the starting material for (-) sparteine that has become unavailable, but that sounds a bit funny, since it would surprise me if the material on the market is synthetic. Sparteine is a naturally occurring alkaloid, found in several species of plant, and it's very hard to compete with isolation of the natural product in those cases.
Perhaps TCI means that the usual plant source is unavailable - that's happened before, too. A spike in Tamiflu demand a few years ago suddenly sent the price of star anise up to record levels, since the chiral starting material (shikimic acid) in the usual synthesis was most conveniently isolated from that source. But for sparteine, it looks as if the isolation comes from plants in the broom family, which are not exactly rare shrubs, so I'm not sure what's going on. Any ideas?