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In this thesis, the application of "counterattack
regent" hexamethyldisilathiane on the accomplishment of a series
of novel double functional group transformations was reported.
Another counterattack regent hexamethyldisilane was used in the
deoxygenation of various organic oxides. Furthermore, the
derivatives of nordihydroguaiaretic acid (NDGA) were synthesized
and characterized which act as a new class of anti-HIV agents.
In Part 1 of this thesis, a series of novel double functional
group transformations were established. These transformations
convert nitrocycloalkenes to carbonyl or alkenyl nitriles in
"one-flask" procedure. Sophisticated mechanisms are involved in
these reactions. Various a-substituted ketoximes can also be
prepared in good yields. In those efficient tandem processes,
hexamethyldisilathiane acts as a counterattack reagent.
In Part 2 of this thesis, deoxygenation of nitrones was achieved
in excellent yields by use of hexamethyldisilane in the presence
of methyl lithium. Similarly, heterocyclic N-oxides were
converted to the corresponding heterocycles in high yields.
These deoxygenation processes involve a new 1,2-elimination of
intermediates containing Si-C-N-O moiety. In Part 3 of
this thesis, the treatment of NDGA with dimethyl sulfate and
potassium carbonate in acetone to give nine methylated products
was reported. Eight of those mono-, di-, tri-, and tetra-O-
methylated NDGAs were isolated. Among the eight different
methylated NDGAs, tetra-O-methyl-NDGA exhibited the strongest
anti-HIV activity. Lignans with methylated catecholic hydroxyl
groups can be produced in large quantities with low cost to
serve as new anti-HIV agent.
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