The Construction Of C-S/C-Se Bond Via C-H Functionalization And Its Application To Flavone And Imidazo [1,2-a] Pyridine Synthesis

Sulfur compounds have been widely used in the fields of materials,chemistry,medicine and so on.Therefore,the preparation of sulfide has been one of the hottest research topics,especially the research on the construction of C-S bond.So,it is more and more popular to find more efficient and concise method for constructing C-S bond.Selenium,as an important element of human body,plays an important role in human body.These important properties of selenium have attracted people's attention,and the preparation of organic selenium compounds is a hot research direction.As a family of sulfur,selenium has different similarities and differences in chemical properties and sulfur,so the synthesis of selenium compounds is different from that of sulfur compounds.Flavonoids is a kind of widespread compounds in nature,and having diverse pharmacological functions.Flavonoids have a variety of physiological activities,such as: Prevention of adult cancer and leukemia,and to reduce the risk of neurodegenerative diseases such as Parkinson's disease(PD),stroke and Alzheimer's disease(AD).Other reports have shown that a synthetic flavonoid derivative can mimic the action of insulin,which may can be used as a treatment for diabetes.The biological activities of flavonoids also include antibacterial and antiviral effects,anti-inflammatory effects,estrogenic and anti estrogenic effects.In addition to these effects,as well as the role of liver protection,diarrhea and antispasmodic effect.Most of the previous studies on flavonoids are based on the purification of flavonoids extracted from natural plants and animals,and then did researches on pharmacological and pharmacodynamic.However,the extraction of Flavonoids from natural sources is not only cumbersome but also having a low yield.There are also some defects in the synthesis of flavonoids by some traditional methods.Using those traditional methods to synthesis flavonoids one by one also very difficult and having some defects which can not be neglected.Therefore,we would like to find a more convenient and efficient method to synthesize flavone derivatives.The imidazo[1,2-a]pyridine compounds are also widely used in natural products.A variety of listed drugs also contain the structure of the imidazo[1,2-a] pyridine compounds.According to the literature,these compounds have a variety of biological activities,such as anti-virus,anti-tumor,anti parasitic,anti microbial,anti fungal,anti-inflammatory and hypnotic effects.Therefore,the study of flavonoids and imidazo[1,2-a]pyridine compounds has been one of the hottest spots in the field of pharmaceutical chemistry.Based on the previous studies and the researches in our group,first we synthesized a series of flavonoids and imidazo[1,2-a]pyridine compounds,as a reactant.Then,some simple and efficient methods were used to realize the sulfur etherification of flavones and selenium etherification of imidazo[1,2-a]pyridine,including:(1)Synthesis of C-S on flavonoid.We put inorganic sulfur,alkyl /aryl halides and flavonoids three component together,using copper iodide as the catalyzer,and then sulfur compounds were synthesized in one step.The method has the advantages of environment friendly and higher yield.(2)The synthesis of C-Se on imidazo[1,2-]pyridine.We put the inorganic selenium source and aryl / alkyl halide and imidazo[1,2-]pyridine together,and the reaction was catalyzed by nano copper oxide in order to synthesis selenium ether compounds.The method is in line with green chemistry and has the advantages of wide applicability and high yield.In summary,two new methods for the formation of C-S bond and C-Se bond have been found in this paper.These methods have many advantages,such as simple operation,wide application,low cost of raw materials,less impurities and high yield.Therefore,these methods not only have the potential of high industrial production,but also provide more choices for the future screening of these two kind of compounds.