The Anomeric EffectThe equilibrium

The Anomeric Effect

The equilibrium preference of most glucosides for the alpha-anomer is referred to as the anomeric effect. If we take away the extraneous functions and substituents from the glucoside structure, it is reduced to the 2-substituted pyran shown on the left in the following diagram. As the two conformational equilibria in the diagram demonstrate, the anomeric effect for a methoxy substituent is sufficient to change the preference for equatorial orientation (a consequence of steric hindrance) to a preference for the axial orientation. The anomeric effect in this case has been estimated at over 1 kcal/mol, but it should be noted that hydrogen bonding in hydroxylic solvents influences this factor.

Kết quả (Anh) 2:

The anomeric Effect The preference of most equilibrium for the alpha-anomer glucosides is Referred to as the anomeric effect. If We take away the extraneous functions and thế from the glucoside structure, it is reduced to the 2-substituted pyran Shown on the left in the drop down diagram. As the two conformational equilibria proven and demonstrated in the diagram, the anomeric effect for a methoxy substituent is đủ to change the preference for Equatorial orientation (a consequence of steric hindrance) to a preference for the axial orientation. The anomeric effect in this case Estimated at over 1 bị kcal / mol, but it shouldnt be noted có hydrogen bonding influences this factor in hydroxylic solvents.