Abstract
在本論文中，報告以反撲試劑六甲基二矽硫醚應用於新穎之雙官能基轉換反應。同時，亦報告另一反撲試劑六甲基二矽烷於各式有機氧化物之去氧反應上之應用。此外，合成出一系列木酚素之甲基化衍生物以作為新型抗愛滋藥物。 在第一部分裡，建立了一系列新型雙官能基轉換反應。此類反應可將硝基環烯於同瓶反應中轉化成含羰基或烯基之氰類化合物，其操作手續簡便但所涉及之反應機構卻極為複雜。利用此反應亦可合成出高產率的各式a取代之污類化合物。在這些高效率的反應中運用六甲基二矽硫醚作為一反撲試劑。 在第二部分中，發現反撲試劑六甲基二矽烷在甲基鋰存在下可對nitrones進行去氧反應而得到高產率之亞胺。在相似反應條件下，含氮雜環氧化物亦可被去氧而得到高產率之雜環化合物。這些去氧反應均藉由含Si-C-N-O結構之中間體經1,2-脫除反應而進行。 在第三部分中，利用硫酸二甲酯及碳酸鉀於丙酮中與nordihydroguaiaretic acid (NDGA)反應而得九種甲基化衍生物。其中八種衍生物可被單離純化出來，並由各種光譜數據確定其結構。在這些衍生物中，肆甲基化NDGA具有最強之抗愛滋病毒活性。利用我們發展出來的方法，將可製造大量價廉之木酚素衍生物，以作為新型抗愛滋病藥物。In this thesis, the application of "counterattackregent" hexamethyldisilathiane on the accomplishment of a seriesof novel double functional group transformations was reported.Another counterattack regent hexamethyldisilane was used in thedeoxygenation of various organic oxides. Furthermore, thederivatives of nordihydroguaiaretic acid (NDGA) were synthesizedand characterized which act as a new class of anti-HIV agents.In Part 1 of this thesis, a series of novel double functionalgroup transformations were established. These transformationsconvert nitrocycloalkenes to carbonyl or alkenyl nitriles in"one-flask" procedure. Sophisticated mechanisms are involved inthese reactions. Various a-substituted ketoximes can also beprepared in good yields. In those efficient tandem processes,hexamethyldisilathiane acts as a counterattack reagent.In Part 2 of this thesis, deoxygenation of nitrones was achievedin excellent yields by use of hexamethyldisilane in the presenceof methyl lithium. Similarly, heterocyclic N-oxides wereconverted to the corresponding heterocycles in high yields.These deoxygenation processes involve a new 1,2-elimination ofintermediates containing Si-C-N-O moiety. In Part 3 ofthis thesis, the treatment of NDGA with dimethyl sulfate andpotassium carbonate in acetone to give nine methylated productswas reported. Eight of those mono-, di-, tri-, and tetra-O-methylated NDGAs were isolated. Among the eight differentmethylated NDGAs, tetra-O-methyl-NDGA exhibited the strongestanti-HIV activity. Lignans with methylated catecholic hydroxylgroups can be produced in large quantities with low cost toserve as new anti-HIV agent.