Molecule of the Day

I was curious about this one after seeing it in the grocery and drugstore so many times. Docosanol, or Abreva, is apparently an effective treatment for herpes labialis (cold sores). It is one of the most boring structures you can imagine, and probably one of the only drugs to have its IUPAC name as its common generic name:

Herpes, is, of course, just another virus. I think the most common treatment is still acyclovir, a guanosine analogue and general antiviral. Docosanol is very, very different structurally, more like a soap (e.g., SDS or sodium laurate.) This no doubt contributes to the fact that it is OTC; most antivirals are analagous to antibiotics, in that resistance often develops. A virus, for example, can mutate, causing drugs that previously fit into its enzymes to cease to work.
Docosanol works by a much more general mechanism that is thought to be less likely to provide selective pressure for resistant viruses. Its mechanism is thought to be analagous to a soap; modulating the structure of the plasma membrane of cells and the lipid envelope of the virus. It seems this works in a way that makes it work pretty well at keeping the virus from injecting its payload into human cells, noted here, for example. Here is also a bit of good background. See you tomorrow!