2,4-DB or 4-(2,4-dichlorophenoxy)butyric acid is a selective systemic phenoxy herbicide used to control many annual and perennial broad-leaf weeds in alfalfa, peanuts, soybeans, and other crops.
The compounds of every Wikipedia article carrying a Chembox or a Drugbox, refreshed daily, with the values their infoboxes give. The pages need JavaScript; the API does not.