Diisopropyl fluorophosphate
Diisopropyl fluorophosphate (DFP) or Isofluorophate is an oily, colorless liquid with the chemical formula C6H14FO3P. It was once used to treat glaucoma and is currently used as an organophosphorus insecticide. It is stable, but undergoes hydrolysis when subjected to moisture.
Source: Wikipedia — Diisopropyl fluorophosphate (CC BY-SA 4.0)