The Reactions Of 1-Sulfonyl-1H-Indazoles And Its Applications In The Synthesis Of Cryptolepine-Type Alkaloids

This thesis mainly introduces the reactions of 1-sulfonyl-1H-indazoles and its applications in synthesis of Cryptolepine-type alkaloids.The thesis is divided into three chapters:The first chapter introduces the biological activity of indazoles.Then outlines the reactions of 1-sulfonyl-1H-indazoles and its preparations.An efficient synthesis of indazoles from readily accessible E/Z mixtures of o-haloaryl N-tosylhydrazones has been discussed.In the second chapter,the studies of Kemp elimination reaction and its application in the synthesis of(-)-Cocaine,Aeroplysinin-1 and Aconitine A ring intermediates are summarized.Then the reactions of 1-sulfonyl-1H-indazoles under basic conditions are discussed,a series of 2-(p-tosylamino)benzonitriles were prepared in good yields,and the 2-(ptosylamino)benzonitriles were transformed into a diverse range of important derivatives in a one-pot reaction.The third chapter,the isolation of Cryptolepine-type alkaloids were introduced,then their pharmacological activities and synthesis methods were summarized.We have developed a novel strategy to synthesize of Quindolinone,Cryptolepinone,Quindoline and N-methyl regioisomer of Cryptolepine,using the Kemp elimination reaction of 1-sulfonyl-1H-indazole as the key step.