피라졸 계통의 유기인계 살충제인 flupyrazofos(O,O-diethyl O-1-phenyl-3-trifluoromethylpyrazo-5-yl phosphorothioate)의 합성공정에서 생산된 원제 1(95.4%), 원제 2(97.6%) 그리고 정제품(99.2%)에 대한 불순물 조성과 함량을 조사하였으며, 이들 원제 및 정제품을 이용하여 in vitro와 in vivo 상에서 acetylcholinesterase (AChE) 활성 저해 정도를 비교 검정하였다. 실험결과 불순물의 조성은 O,O,O-triethylthio-phosphoric acid (TEA), 1-phenyl-3-trifluoromethyl-5-ethoxy pyrazole(PTMEP), O,O-diethyl O-1-phenyl-3-trifluoromethylpyrazo-5-yl phosphoric acid ester(flupyrazofos oxon), O,S-diethyl O-1-phenyl-3-trifluoromethylpyrazo-5-yl phosphorothionate (S-ethyl flupyrazofos)이었으며, 이들 불순물들의 함량이 원제 중에서 전반적으로 높았다. In vitro 상에서 AChE 저해는 불순물들이 많은 원제 1에서 가장 빠르게 저해되었으며, 생쥐 뇌 AChE (in vivo)에 대한 $I_{50}$ 값은 원제 1과 2가 정제품 보다 40% 이상 높았다. 이는 정제품에 비하여 원제 중에 더 많이 함유된 flupyrazofos oxen과 S-methyl flupyrazofos에 의한 영향일 것으로 판단되었다.
Flupyrazofos (O,O-diethyl O-1-phenyl-3-trifluoromethylpyrazo-5-yl phosphorothioate) is an organophosphorus insecticide with a pyrazole moiety which is newly developed and commercialized by SUNGBO chemical company and Korean Research Institute of Chemical Technology for effectively control against diamond back moth. This study was conducted to determine the composition and quantity of impurities in technical 1 (94.5%), technical 2 (97.6%) and purified (99.2%) flupyrazofos using GLC/MSD. Bimolecular inhibition rate constant($k_i$) with acethylcholinesterase (in vitro) and $I_{50}$ with mouse brain acetylcholinesterase (in vivo) were measured for comparing inhibitory patterns of two technicals and purified flupyrazofos. Impurities of flupyrazofos were identified as O,O,O-triethylthio-phosphoric acid (TEA), 1-phenyl-3-trifluoromethyl-5-ethoxy pyrazole(PTMEP), O,O-diethyl O-1-phenyl-3-trifluoromethylpyrazo-5-yl phosphoric acid ester(flupyrazofos oxen), O,S-diethyl O-1-phenyl-3-trifluoromethylpyrazo-5-yl phosphorothionate (S-ethyl flupyrazofos). In in vitro, technical 1 showed the fastest inhibition on AChE activity among them. And technical 1 and 2 showed 40% higher in vivo inhibition against mouse brian AChE than purified flupyrazofos did. These results could be caused by the impurities such as flupyrazofos oxen and S-methyl flupyrazofos contained in technical grades of flupyrazofos.
