Synthesis Of C2-methyl Branched Poly Hydroxy Cyclic Nitrone And Its Application In The Synthesis Of The Aza Sugar

Azasugar, also called iminosugar and polyhydroxylated alkaloid, can be seemedas the derivatives of sugar in which oxygen in the ring have been replaced by nitrogen.As a kind of potent glycosidase inhibitors, azasugars show great bioactivity onantitumor, antivirus, antidepresent and anti-metabolic disorders. Nitrone, a greatimportant synthon in organic synthesis, can not only proceed1,3-dipole cyclicaddition, but also introduce multiple chiral center diastereoselectively. Thisdissertation focus on the synthesis of C2-methyl polyhydroxylated cyclic nitrone andthe application in the synthesis of C2-branched azasugars.First of all, C2-methyl sugar was prepared from D-glucose, followed byintramolecular N-alkylation of oxime to afford C2-methyl five-member ring andsix-member ring cyclic nitrone.Then, starting from C2-methyl five-member ring cyclic nitrone, some C2-methyl azasugars were synthesized through simple nucleophilic addition, and the absoluteconfiguration was determined by NMR.