微波辐射下合成2-甲硫基-3-氰基-7-取代苯基吡唑并[1,5-a]嘧啶及生物活性的研究

Facile Synthesis of Pyrazolo[1,5-a]pyrimidine Derivatives via Microwave Irradiation and Biological Activity Research

利用取代烯胺酮1与3-甲硫基-4-氰基-5-氨基-1H-吡唑(2)反应,用传统和微波2种方法合成了6种化合物2-甲硫基-3-氰基-7-取代苯基吡唑并[1,5-a]嘧啶(3a～3f),化合物的结构均经元素分析,IR,1H NMR所证实.对比两种方法,微波辐射具有用时少、环境友好、易纯化和产率高的特点,同时,探讨了反应可能的机理,并对所有化合物的杀菌和除草活性进行了测试.

A series of 2-methylthio-3-cyano-7-substituted pyrazolo[1,5-α]pyrimidines （3a～3f） by the reaction of substituted enaminones 1 with 3-methylthio-4-cyano-5-amino-1H-pyrazole （2） have been conveniently synthesized via conventional method and microwave irradiation technique. By comparison of the two methods, microwave irradiation possessed such advantages as short reaction time, environmentally benign procedures, easy purification and high yield over the conventional stirring at ambient temperature. The structure of all compounds was characterized by elemental analyses, IR, ^1H NMR spectra. In the meantime, the plausible mechanism was discussed. The preliminary test showed that certain compounds had somewhat herbicidal activities.