Studies On Synthesis Procedure And Conditions Of Two Classes Of Heterocyclic Nitrogenous Compounds By Dehydrogenation

Hantzsch 1,4-dihydropyridines (Hantzsch 1,4-DHP) attract great interest for their importance in organic synthesis and biochemistry. They can not only be extensively used as starting materials or intermediates in organic synthesis, but also be recognized as calcium channel blockers for the treatment of cardiovascular diseases. Their biological significance has been greatly recognized since they are discovered to be the active part of NADH, the essential reducing coenzyme in animals. It is interesting that 1,4-DHP systems are oxidatively transformed into the corresponding pyridine derivatives both during the redox reaction of NADH and in the course of drug metabolism. These discoveries make dehydrogenation of 1,4-DHP a convenient method for synthesis of pyridines, and furthermore, endow it with pharmacological and biological significance. Therefore, studies on dehydrogenation of 1,4-DHP continue to be important both in organic synthesis and biochemistry.The excessive accumulation of free radicals or substances that can produce free radicals in human body can cause many diseases such as heart disease, aging, etc. In order to examine the potential application of 1,4-DHP to consume excess peroxide or oxygen free radicals in human body thus delay aging, studies on the reaction procedure and mechanism of 1,4-DHP with peroxide compounds can be of healthy and pharmacological significance. Based on the analysis and summary of related literature, several 1,4-DHP have been designed and synthesized, and peracetic acid as a new oxidation reagent was also investigated for 1,4-DHP. It was observed that the reaction of peracetic acid with 1,4-DHP failed to work well for its poor selectivity. After careful investigation into the reaction, it was found that 1,4-DHP can be quickly aromatized to their corresponding pyridine derivatives by diatomite-supported peracetic acetic acid at room temperature or 0-5 ℃ in moderate to good yields.In addition, the complex CuCl(OH).TMEDA has been synthesized and...