Design And Synthesis Of Heterocycles Containing Nitrogen Atom

Up to date, hundreds of millions of organic compounds have been prepared, however, only small amounts of them have some bioactivities, most of them are heterocyclic compounds. Therefore, the design and synthesis of heterocyclic compounds having some bioactivities attract more and more chemists and pharmacologists for doing research in this field.Author had started the research on design and synthesis of heterocycles several years ago, mainly focused on the design and synthesis of imidazole, thiazole, tetrazole derivatives and their glucosides, in which most of them may have some particular bioactivities. Furthermore, in order to get a large numbers of these compounds, the same reactions were proceeded on solid phases such as Marrifield resin, Wang resin. In our investigation, several new reactions have been discovered, and 116 new heterocyclic compounds have been prepared, these results are included in 6 chapters.The chapter 1 introduces the background of imidazole, thiazole, tetrazole derivatives and their glycosides, and organic solid phase research.The chapter 2 concentrates on the design and synthesis of l-aroyl-3-aryl-4-substituted imidazoline-2-thiones and l-aroyl-3-aryl-4-substituted imidazole -2-thiones by the reaction of l-aroyl-3-arylthioureas with a variety of carbonyl compounds bearing a-H in the presence of bromine and triethylamine. The novel synthetic method included the following merits, such as easy available starting materials, simple manipulation, mild reaction condition and high yields. 18 new imidazoline-2-thiones and 18 imidazole-2-thiones have been prepared, respectively. In addition, author succeeded in design and synthesis of new 2,4-imidazolidinediones and 2-thioxo-4-imidazolidinones by the reaction of a-benzoylhemithioacetal with ureas and thioureas, the new synthetic route has similar merits as mentioned above. All the compounds obtained were confirmed byIR, 'HNMR, 13CNMR, MS and elemental analyses. Finally, the reaction mechanisms were proposed for these reactions.The chapter 3 focuses on the design and synthesis of new thiazole derivatives. When changing the substituents at 3-position of the aroylthioureas and the structures of carbonyl compounds, the corresponding thiazole derivatives instead of imidazoles have been obtained. 12 new 4-methyl-2-aroylimino-3-(4-substituted phenyl) thiazoles and 6 4-methyl-2-(4-Hydroxyaroylimino)-3-aryl thiazoles were prepared. The structures of all the thiazole derivatives were confirmed by IR, 'HNMR, 13CNMR, MS and elemental analyses and a mechanism was proposed for them.The chapter 4 describes the synthesis of thiazole derivatives on the solid phase such as Merrifield resin, acid resin and Wang resin, the results showed that the products have excellent purity, simple manipulation and a lot of analogues can be obtained at the same time.The chapter 5 centers on the design and synthesis of tetrazoles named N-(biphenylmethyl)-2, 4-imidazolinedione derivatives. The structures of all the compounds were confirmed by IR, 'HNMR, 13CNMR, MS and elemental analyses.The chapter 6 makes a study on the design and synthesis of new glycosides, which prepared from imidazole, thiazole and tetrazole aglycones mentioned above and glucose derivatives by phase transfer catalysis under the moderate reaction condition. The structures of all the glycosides were confirmed by IR, 1HNMR, 13CNMR and MS, and found that they all have the (-configuration. Finally, the structure of l-(p-D-2', 3', 4',6'-tetraacetylglucopyranosyl)-4-[2'-(benzoylimino)-4'-methyl-3'-thiazolyl] benzoate was confirmed by X-ray diffraction analysis.