Dissociation constants of D-galacturonic and D-glucuronic acid and their О-methyl derivatives
نویسنده
چکیده
Dissociation constants (pK, 20°C) of D-galacturonic acid, D-glucuronic acid, their O-methyl derivatives, as well as of the corresponding 4,5-unsaturated substance have been determined by means of discontinuous Potentiometrie titration. The found pK values have been interpreted from the point of view of inductive and mesomeric effects, and nonbonding interactions. It is demonstrated that the effect of the methoxy substitution at various positions of D-galacturonic acid on its acidity has an additive character.
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