Study On Enantioselective Environmental Behavior Of Triadimefon

Up to2006, over40%of used pesticides are chiral in the world. Different enantiomers of the chiral pesticides often exhibit different bioactivity and toxicity in the environment. Now research on enantioselective behavior of the chiral pesticides was a hot spot in chemistry and environment, its had great importance on the elucidation and value of practical application, and evaluate ecological risk of the chiral pesticides in the environment.In this paper, three triazole pesticides, i.e., Triadimefon, Triadimefon A and Triadimefon B were investigated in details related to chiral separation and enantioselective degration in soils, organic solvents and buffer solution. Following experimental contents and conclusion were conducted:(1) Enantiomeric separation of chiral pesticidesEnantiomers of Triadimefon, Triadimefon A and Triadimefon B were successfully using chiral HPLC.(2) Enantioselective degradation of Triadimefon in two kinds of soilThe degradation of Triadimefon was faster in Wuhan soil than in Baoding soil, and had the transformation from Triadimefon A to Triadimefon B. Through the sterilization the contrast research, the enantioselective degradation of Triadimefon was mainly biologically mediated in the Baoding soil and Wuhan soil.(3) Enantioselective degradation of Triadimefon A and Triadimefon B in two kinds of soilsThe degradation of Triadimefon B was faster in Wuhan soil than in Baoding soil, and obvious enantioselectivity was observed in Wuhan soil and Baoding soil with1R,2R-Triadimefon faster degraded than1S,2S-Triadimefon. The degradation of Triadimefon was faster in Wuhan soil than in Baoding soil, and had the transformation from Triadimefon A to Triadimefon B. Respectively the1R,2S-Triadimefon was degraded faster than IS,2R-Triadimefon in the two kinds of soils. However, transformed Triadimefon B, its ER value was firstly increase, and then decrease. Through the sterilization the contrast research, the enantioselective degradation of Triadimefon A and Triadimefon B were mainly biologically mediated in the Baoding soil and Wuhan soil.(4) Enantioselective degradation of1S,2R-Triadimefon A in two kinds of soilsThe degradation of1S,2R-Triadimefon A showed the half-lives was61.9d in Baoding soil, and37.7d in Wuhan soil. The experiment in Baoding soil showed, transformed Triadimefon B, its generation and transformation degree not had shown a big difference. However, in the experiment in Wuhan soil showed that transformation was mainly from1S,2R-Triadimefon into1S,2S-Triadimefon.(5) Chiral stability of Triadimefon A in organic solvents and buffer solutionChiral stability of Triadimefon A in organic solvent and buffer solution was studied. under the condition of25℃, light training avoided, Triadimefon A in the buffer solution and methanol were not existed degradation and enantiomers transformation phenomenon.