70年代以前开发的有机磷杀虫剂品种中大多含有两个低烷氧基,因此具有对称结构(1)。而70年代以后,出现了一类含烷硫基和不对称磷原子的化合物(2),通常把它称为S烷基不对称磷酸酯类杀虫剂。这类杀虫剂的代表性品种有速丙磷(Heterophos)、丙溴磷(Pro-fenofos)、硫醚磷(Diphenprophos)、吡唑硫磷(Pyraclofos)、丙硫磷(Prothiofos)和甲丙硫磷 Organophosphorus insecticide varieties developed before the 1970s mostly contain two lower alkoxy groups and therefore have a symmetrical structure (1). Since the 1970s, a class of compounds containing alkylthio and asymmetric phosphorus atoms (2) has emerged, commonly referred to as S-alkyl asymmetric phosphate pesticides. Representative varieties of such insecticides are Heterophos, Pro-fenofos, Diphenprophos, Pyraclofos, Prothiofos and Methylparaben Phosphorus