Study On The Methodology Of Novel Thiapyran[2,3-d]Pyrimidins And Spiropyrrolidines

Thiapyran[2,3-d]pyrimidins and spiropyrrolidines have gained significant attention due to their interesting biological activities and pharmacological activities such as antimicrobial, antitumor, and antileukemic properties.β-(2-chloroaroyl)-heterocyclic ketene aminals are good synthons in the formation of C-C bond and C-N bond because of their high reactivity. Multicomponent reactions (MCRs) are important for generating high levels of diversity, as they allow more than two building blocks to be combined in a practical, time-saving, one-pot operation, giving rise to complex structures by simultaneous formation of two or more bonds from simple substrates. People widely use the cycloaddition reaction of 1,3-dipolar to produce many biologically active spiroheterocyclic compounds, since there is wide range of 1,3-dipolar which can be conveniently yielded. In the second chapter, twenty-three new thiapyran [2,3-d]pyrimidins were synthesized by the reactions of heterocyclic ketene aminals, chlorides and potassium thiocyanate. Different solvents and catalysts were investigated. Using acetonitrile as solvent and triethylamine (20 %) as catalyst were deemed to the optimum reaction condition. In this reaction, eight different active sites were involved; one C-C bond, one C-S bond, two C-N bonds and two new rings were constructed with all reactants which efficiently utilized via a sequence of imidazole ring-open, Michael addition, cyclization and intramolecular nucleophilic substitution reactions. It fully reflects the"atom economy"of this reaction.In the third chapter, twenty-four new spiropyrrolidines were synthesized by the reactions of indene-1,2,3-trione, benzene-1,2-diamine, sarcosine, aldehyde and 1,3-indanedione or malononitrile. Different solvents were investigated. The solventhermal synthesis was firstly employed in 1,3-dipolar cycloaddition reaction while use malononitrile as reactant. The high atom economy and ecologically benign process are developed since only four molecules of water and one molecule CO2 are lost; and multiple bonds and stereocenters are formed in a single reaction.The structures of all the synthesized compounds were characterized by IR, 1H NMR, 13C NMR.Three single-crystals were cultured and the structure of the unknown compounds could be confirmedconveniently by X-ray single-crystal diffract -ion analysis.