Studies On Stereoselective Ring Opening Reactions Of Three-Membered Heterocycles With Nitric Oxide Mediated By Free Radicals

In this dissertation I will present my study on stereoselective ring opening reactions of three-membered heterocycles with nitric oxide(NO)mediated by free radicals.This dissertation is divided into 3 chapters as follows.The first part opens the great roles of NO in biology.As conceived by Louis J. Ignarro,Ferid Murad and Robert F.Furchgott,who shared the 1998 Nobel Price for Medicine,the mechanism of NO acting as the endothelium-derived relaxing factor (EDRF)is described in this section.In addition,a description of NO's chemical actions is given.Otherwise,the chemistry of epoxides and aziridines is also reviewed in this chapter,especially focused on their ring opening reactions and rearrangements initiated by free radicals.In the second part,the results are presented in details.We found the reaction of epoxides with NO occurred highly stereoselectively,affording corresponding ring-opened products.A possible mechanism is suggested to trace out the ring opening pathway.The third part develops the ring opening reactions to aziridines with NO. Mechanisms of the reactions are described.Meanwhile,differences in the ring opening reaction of aizidines and epoxides with NO are discussed.