Synthesis And Bioactivity Test Of Novel Pyrazole Compounds

In order to search for new route method what is more simple, more efficient and more environmental friendly for the synthesis of pyrazole compounds and on the basis of our former work, we design a new routeto synthesize pyrazole ring. Finally we successfully synthesized 16 unreported compounds. We hope that the new route for synthesis of pyrazole compounds can be used in the special field of medicine, pesticide, paint and which field needs pyrazole compounds. 1 、 Through Friedel-Crafts Acyl Reaction between benzene compounds and acetylchloride, we get ketone. Then ketones react with hydrazine hydrate to synthesis Hydrazone. Hydrazonesinterconvert itsresonance called alkene hydrazine while acid as catalyst. And then hydrazones react with 2,4-pentanedione to form pyrazole ring(route as follows). The route makes the ketones directly transition to the pyrazole compounds a reality. The reaction process is a direct dehydration to form ring. The process are simple,environmental friendly and the reaction yield reached above 90%. 2、In order to study of pyrazole compounds further, we used the pyrazole compounds which is synthesised by new route as substrate react with N-bromosuccinimide, to replaced the hydrogen of alkenyl, then form halogenated alkenyl pyrazole compounds. We synthesized 16 compounds what have not been reported. The target compounds of general formula as follows:Two series of compounds were characterized by 1HNMR spectra,IR spectra and MS spectra. And the spectrum was primary analyzed. Preliminary study on the mechanism of synthesis of pyrazole ring and the method that the replace of double bond hydrogen.We have commissioned the Shanghai Institute of Organic Chemistry to complete toxicity prediction of the certain target compounds. The prediction results show that the designed target compounds(6a and 6c) have a certain biological activity.We have commissioned the Zhejiang Research Institute of Chemical Measurement Center of Safety Evaluation to complete insecticidal activity, herbicidal and fungicidal activity screening of the compounds(6a-6i). The experimental results show that the compound(6c) has certain inhibiting effect on cucumber downy mildew. The compound(6a) has a certain inhibiting effect on cucumber powdery mildew. The compound(6c) shows high inhibitory activity on the stem of sorghum, barnyard grass, rape and radish. Key word: pyrazole;hydrazone;alkene hydrazine;2,4- pentanedione;halogenated...