| R & D of agrochemicals was a great progress and contribution in the 20th century. Since the 40's of the 20l century, agrochemicals were widely used in a variety of crops and became the most important tools which avoid or reduced the damage from many kinds of diseases, pests and weeds, greatly raised the output of crops and promoted the rapid development of agriculture, basically met the needs of increasing population for food. On the other hand, however, the negative influence of agrochemicals on human beings and environment and relevant social factors have been gradually understood and paid attention to by people. For example, the first-generation (organochlorine, organophosphorus) and the second-generation (carbamate, pyrethroid) pesticides extensively used at present were also harmful to benefit insects, wild animals, fishes, natural environment and even to human beings. Therefore, modern new varieties of pesticides must be high efficient, low toxic, low residue, safe to the human race and mammals, and friendly to environment. The insect growth regulator, as a functional mechanism, exactly meets such a need.At present, the insect growth regulatorsas chiefly include juvenile hormone analog, moeting hormone analog and chitin synthesis inhibitor, etc., which derived from the simulation and development of the inner hormone within insects. Since they are similar to the hormone structure or function within insects and that take the growth system unique to insects as the target of attack in terms of functional mechanism, These hormone substances, unique to insects, can prevent and eliminate insect pests in a selective way, without producing resistance and harm to natural enemies, human beings and domesticated animals, hence enjoying new and special characteristics of eliminating insect pests, obviously featured by low toxicity, high efficiency and environmental friendliness.Directional synthesis has become one of the main methods for developing new pesticides in recent years. Active elements in natural substances or active elements in some kinds of pesticides already successfully developed are taken as the leading structure in addition to applying the principle of moleculer bioisosterism and the method of analoguesynthesis for making innovative structural modification, hence greatly improving and elevating the original bio- activeness. Bio-sifting has further helped to have found chemical compounds with the same functional mechanism and greater activeness. Compared with traditional random composition frequently used, this kind of innovative way of producing new pesticides is marked by a clearer and more directional aim, higher rate of hits and less expense, hence desirably fitting the concrete situation of China.As mentioned above, we have chosen the insect growth regulator (N-tert-butyl biacyl hydrazine) featured by meeting hormone analog and low toxicity as the target for research to deal with Lepidoptera pests which are the most harmful to crops. Directional synthesis is hoped to compose and sift new chemical compounds with relatively high efficiency for further bringing about new pesticides characterized by high efficiency, low toxicity and environmental acceptable.The general formula of N-tert-butyl biacyl hydrazine derivatives is as follows:with different substituted radicals, and N-tert-butyl biacyl hydrazine ()is a basal active part of the general formula. Mail research work of this article:(1) Using N-tert-butyl biacyl hydrazine as the lead structure to make lead design via moleculer bioisosterism and analogue synthesis method. RI and R2 were selectively and purposely substituted with different radicals. 46 objective compounds were synthesized as a result of combining the above lead structures with a phonyl, heterocycle or fused heterocycle radical with different radicals. After refined, these compounds were respectively detected by nuclear magnetic resonance, High Performance Liquid Chromatography(HPLC), Liquid Chromatography and Mass Spectrometry(LC-MS), a...
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