Synthesis And Characterization Of Novel Pyrazole Derivatives

In pharmaceutical and pesticide fields, heterocyclic compounds always play a very important role. Research on the synthesis of heterocyclic compounds which have biological activity become a hot topic in the research of pharmaceutical and pesticide fields. Pyrazole is an important five-membered heterocyclic ring system, that has different biological activities due to the four substitution position of different substituents. It has attracted considerable attention to the experts owing to the different biological activities such as anti-bacterial, anti-tumor, herbicidal. anti-inflammatory.1,5-benzothiazepine is an important seven-membered heterocyclic ring system. They possess a number of biological activities such as anti-ulcer, hypotensive, anti-bacterial, anti-tumor, anti-depressant.1,5-benzothiazepine derivatives have been used as anxiolytics, hypnotics, cardiovascular drugs in clinical. Meanwhile, antihypertensive drugs which have1,5-benzothiazepine active components are already on the market. Diltiazem is a typical1,5-benzothiazepine drugs. Therefore, scientists pay more and more attention in research of this kind of the compounds. In addition,1,2,4-triazole compounds have the advantages of high efficiency, broad spectrum, and they have a number of biological activities such as hypotensive, anti-bacterial. Since the bactericide of ketotriazole has been used, experts pay more and more attention in research of this kind of the compounds.Considering the combination principles for drug design, the compounds containing different heterocyclic in a single molecular can increase the biological activity. Therefore, our major work is put the three compounds of pyrazole,1,5-benzothiazepine and triazole into a single molecular. Consequently, we prepared a series of novel tricyclic derivatives via1,3-dipolar cycloaddition reaction with potential biological activities.The thesis includes two major parts:The first part is literature review:This part introduce the important synthetic methods and biology activities of pyrazole,1,5-benzothiazepine and triazole derivatives. Meanwhile, elaborate1,3-dipolar cycloaddition reaction.The second part is experimental content. Major works as follows:1. Synthesis of pyrazole derivatives containing triazole moiety.Chalcone containing triazole moiety synthesized from3-methyl-1-phenyl-5-(1,2,4-triazole-1-yl)-4-formylpyrazole and4-chloro-benzohydroximinoyl chlorides, which reacted with o-aminothiophenol to give1,5-benzothiazepine containing triazole moiety. Finally, a series of novel pyrazole derivatives are prepared with chalcone/1,5-benzothiazepine and benzohydroximinoyl chlorides respectively via1,3-dipolar cycloaddition reaction.2. Synthesis of3,4-diaryl-1-[3-methyl-1-phenyl-5-(1,2,4-triazole-1-yl)-pyrazolo-4-yl]-3a,4,5,11-4H-[1,2,4]oxadiazole[5,4-d]1,5-benzothiazepines via1,3-dipolar cycloaddition reaction.In this part, pyrazolohydroximinoyl chloride is prepared step by step, which reacted with1,5-benzothiazepines to give3,4-diaryl-1-[3-methyl-1-phenyl-5-(1,2,4-triazole-1-yl)-pyrazolo-4-yl]-3a,4,5,11-4H-[1,2,4]oxadiazole[5,4-d]1,5-benzothiazepi-nes via1,3-dipolar cycloaddition reaction.3. Synthesis of3,4-diaryl-5-[3-methyl-1-phenyl-5-(1,2,4-triazole-1-yl)-pyrazolo-4-yl]-1,2,4-oxadiazolines via1,3-dipolar cycloaddition reaction.In this part, schiff bases of3-methyl-1-phenyl-5-(1,2,4-triazole-1-yl)-4-formylp-yrazole are prepared with3-methyl-1-phenyl-5-(1,2,4-triazole-1-y])-4-formylpyrazole and para-substituted aniline. Then,3,4-diaryl-5-[3-methyl-1-phenyl-5-(1,2,4-triazole-1-yl)-pyrazolo-4-yl]-1,2,4-oxadiazolines are prepared with schiff bases of3-methyl-1-phenyl-5-(1,2,4-triazole-1-yl)-4-formylpyrazole and4-chloro-benzohydr-oximinoyl chlorides via1,3-dipolar cycloaddition reaction.The structures of the new compounds were confirmed by IR, MS,1H NMR and elemental analyses. In addition, we give the single crystal discussion to some of the target compounds...