PESTICIDES REPORT .37. CHIRALITY IN SYNTHETIC AGROCHEMICALS - BIOACTIVITY AND SAFETY CONSIDERATION (TECHNICAL REPORT) (VOL 69, PG 1335, 1997)

Most synthetic agrochemicals with chiral structures are marketed as ra cemates even though the desired biological activity may be derived fro m only one enantiopure isomer. However some synthetic agrochemicals su ch as pyrethroid insecticides, aryloxypropanoate herbicides and triazo le fungicides are marketed as the most biologically active enantiopure isomer. Numerous reports describing the relative biological actitivit es, preparations and analyses of enantiopure agrochemicals are availab le. Some examples of how different enantiomers in racemates are select ively metabolized have also been reported. When agrochemicals have chi ral structures, efforts should be made to define the mode of action, e lucidate metabolic pathways and to define the human and environmental toxicity of each enantiopure isomer. If there are large differences in the biological activities of individual enantiomers in racemates, it is desirable to develop and use only the enantiopure isomer with the h ighest sought-after biological activities.