The enantiomers of sulprofos [O-ethyl O-[4-(methylthio)phenyl] S-propyl phosphorodithioate] and its phosphorothiolate analogue were prepared by acid-catalyzed ethanolysis of the diastereoisomers of N-[(2S)-2-(carboxyethyl)pyrrolidinyl] S-propyl phosphoramidodithioate and the corresponding phosphoramidothiolate, respectively. Peracid oxidation converted the phosphorodithioate and phosphorothiolate to the sulfone derivative of sulprofos oxon. Analogous procedures were used to resolve profenofos [O-(4-bromo-2-chlorophenyl) O-ethyl S-propyl phosphorothiolate] and its O-methyl and O-pentachlorophenyl analogues. The (+)-isomers are most toxic to house flies in the sulprofos series and the (-)-isomers in the profenofos series. The chiral specificity is reversed in each case relative to potency as inhibitors of house fly head acetylcholinesterase (AChE) activity. Most of these phosphorothiolates are activated to more potent inhibitors of electric eel AChE on coincubation with a mouse liver microsomal oxidase system. (+)-Profenofos and (-)-sulprofos oxon sulfone are the only exceptions, undergoing stereoselective detoxification when unwashed microsomes are used.
All Science Journal Classification (ASJC) codes
- Agricultural and Biological Sciences(all)