The Smallest Drugs

Here is the updated version of the "smallest drugs" collection that I did the other day. Here are the criteria I used: the molecular weight cutoff was set, arbitrarily, at aspirin's 180. I excluded the inhaled anaesthetics, only allowing things that are oils or solids in their form of use. As a small-molecule organic chemist, I only allowed organic compounds - lithium and so on are for another category. And the hardest one was "Must be in current use across several countries". That's another arbitrary cutoff, but it excludes pemoline (176), for example, which has basically been removed from the market. It also gets rid of a lot of historical things like aminorex. That's not to say that there aren't some old drugs on the remaining list, but they're still in there pitching (even sulfanilamide, interestingly). I'm sure I've still missed a few. What can be learned from this exercise? Well, take a look at those structures. There sure are a lot of carboxylic acids and phenols, and a lot more sulfur than we're used to seeing. And pretty much everything is polar, very polar, which makes sense: if you're down in this fragment-sized space, you've got to be making some strong interactions with biological targets. These are fragments that are also drugs, so fragment-based drug discovery people may find this interesting as the bedrock layer of the whole field. Some of these are pretty specialized and obscure - you're only going to see pralidoxime if you have the misfortune to be exposed...
Source: In the Pipeline - Category: Chemists Tags: Chemical News Source Type: blogs