Synthesis Of Pyrazolines And Their Derivatives And Study Of Their Antimicrobial Activity

This dissertation consists of four chapters. Chapter one is mainly about the research development of pyrazolines and their derivatives in recent years. Chapter two is the studies of microwave-assisted synthesis of pyrazolines and their derivatives; Chapter three is about the research of antimicrobial activity of the pyrazolines; In the last chapter, we studied the synthesis of medicinal intermediates 1, 4-N, N-substituted piperazines.There are two parts in chapter one. First, we summarized some researches of the methods to synthesize various of pyrazolines and their bioactivities. Part two we synthesized a series of derivatives of a,α'-bis(benzylidene)cycloalkanones and a, a'-bis(benzylidene)acetones-Pyrazolines in claasical reflux conditions. We studied the influence of size of rings and the substituents of the materials on the reacton, and optimized the reaction conditions.In chapter two, we first reviewed the applications of microwave technology in synthesis of pyrazolines and their derivatives, then synthesized a series of pyazolines and hydrazones with nitro group. The results obtained indicate that, this easy, simple, efficient and rapid synthetic methodology is extremely convenient for the reaction. At last, we analyzed results of the reactions and proposed a possible mechanism.We studied the antimicrobial activity of the pyrazolines and their derivatives in chapter three. The results proved that there were different bacteriostasis effects of Gram-Positive-Bacteria and Gram-Negative-Bacteria, which is broad-spectrum.In chapter four, we summarized the importance of synthesis of 1, 4-N, N-substituted piperazines, and designed a novel way to synthesize 1, 4-N, N-substituted piperazines. The results obtained indicate that, this method has some advantages such as simple operation, mild condition, shorter reaction times and higher purity.