C=C Bond Formation
2.6
369
⊡ Scheme 43
⊡ Scheme 44
The glucose analog, 3-deoxy-3-C-methylene-D-ribo-hexose (102) is a substrate of a D-xylose
isomerase. The efficient synthesis from 3-deoxy-3-C-methylene-glucofuranose (101 prepared
by the classical method according to [92]) was described recently ( > Scheme 44) [93].
The key step in the preparation of 5,6-dihydro-δ-pyrones with an incorporated 1,3-polyol system (an example, compound 105 possessing inhibitory activity against C. cucumerinum is
shown in > Scheme 45) consisted of formation of a 2,3-unsaturated furanose derivative 104,
which was prepared from 103. Abstraction of an acidic proton from the C-2 induced β-elimination, providing the desired target 104 [94].
⊡ Scheme 45
2.6
369
⊡ Scheme 43
⊡ Scheme 44
The glucose analog, 3-deoxy-3-C-methylene-D-ribo-hexose (102) is a substrate of a D-xylose
isomerase. The efficient synthesis from 3-deoxy-3-C-methylene-glucofuranose (101 prepared
by the classical method according to [92]) was described recently ( > Scheme 44) [93].
The key step in the preparation of 5,6-dihydro-δ-pyrones with an incorporated 1,3-polyol system (an example, compound 105 possessing inhibitory activity against C. cucumerinum is
shown in > Scheme 45) consisted of formation of a 2,3-unsaturated furanose derivative 104,
which was prepared from 103. Abstraction of an acidic proton from the C-2 induced β-elimination, providing the desired target 104 [94].
⊡ Scheme 45