<P> Metolachlor is an organic compound that is widely used as an herbicide . It is a derivative of aniline and is a member of the chloroacetanilide family of herbicides . It is highly effective toward grasses . </P> <P> Metolachlor was developed by Ciba - Geigy . Its acts by inhibition of elongases and of the geranylgeranyl pyrophosphate (GGPP) cyclases, which are part of the gibberellin pathway . It is used for grass and broadleaf weed control in corn, soybean, peanuts, sorghum, and cotton . It is also used in combination with other herbicides . </P> <P> Metolachlor is a popular herbicide in the United States . As originally formulated metolachlor was applied as a racemate, a 1: 1 mixture of the (S) - and (R) - stereoisomers . The (R) - enantiomer is inactive, and modern production methods afford only (S) - metolachlor, thus current application rates are far lower than original formulations . </P> <P> Metolachlor is produced from 2 - ethyl - 6 - methylaniline (MEA) via condensation with methoxy acetone . The resulting imine is hydrogenated to give primarily the S - stereoisomeric amine . This secondary amine is acetylated with chloroacetylchloride . Because of the steric effects of the 2, 6 - disubstituted aniline, rotation about the aryl - C to N bond is restricted . Thus, both the (R) - and the (S) - enantiomers exist as atropisomers . Both atropisomers of (S) - metolachlor exhibit the same biological activity . </P>

Where is metolachlor most commonly found (choose 2)