16 



IMMUNO-CATALYSIS 



solvation is not known and it is really equally misleading to write a 

 definite structure, such as H3O+ for the hydrogen ion. Secondly, it is 

 not general practice to show the solvation of other ions, although nearly 

 all ions are solvated because of the ion-dipole or ion-induced dipole 

 forces present in their solutions. For these reasons the solvation will be 

 shown only when it serves the purpose of clarifying the interaction of 

 the solvent with the acids and bases present. 



General Acid and Base Catalysis. The role of acid or base as a 

 catalyst in reactions involving esterification, hydrolysis, condensations, 

 and carbonyl addition reactions is to accentuate the difference in 

 electron density between the two reacting centers, as indicated in the 

 following examples. 



a. Mutarotation of Glucose by Acid and Base Catalysis. It is 

 known that when glucose is dissolved in water its specific rotation is 

 + 110° which gradually sinks to +52.5° on standing. This change, 

 known as mutarotation, is the result of the transformation of a-glucose 



HO-C 

 HO-C 



^C-OH 



O 



C— CHoOH 

 /\H 



H OH 

 a-d-Glucose 



d-Glucose 



^-d-Glucose 



