Envelope conformation reductions

The FOZ 310, derived from the corresponding hydrocarbon bearing a C=C link, is unusually stable (m.p. 159-161 °C) and resistant to reduction by NaBHt. Its strucmre was elucidated by XRD analysis, showing the same O envelope conformation of 288,... 

Alkylation of the lactol HO-group also enhances the anomeric effect (Table 4.7). A reduction of the dielectric constant of the solvent (e. g., transition from water to methanol), resulting in an increase in the dipole-dipole interaction, also enhances the anomeric effect. Conformational isomers of fura-nose also occur since its ring is not planar. There are two basic conformations, the envelope (E) and the twist (T), which are the most stable in solu-... 

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