The conformational dependence of the hydroxymethyl group of the struct
ural nature of the substituent at the anomeric carbon (aglycone) is re
vealed in the present spectroscopic study, based on CD and NMR, of syn
thetic glycopyranoside systems. The perturbation generated by the subs
tituents, achiral and chiral secondary alcohols of different sizes, co
mes mainly from the exo-anomeric stereoelectronic effect.