Dissociation Constants of Cystine, Cysteine, Thioglycollic Acid and α-Thiolactic Acid

Abstract

MATHEWS and WALKER [1909] and, in greater detail, Dixon and Tunnicliffe [1923] have demonstrated the great significance of the hydrogen ion activity in relation to the rates of oxidation and of autoxidation of a number of thioacids. To assist the analysis of these results and of certain observations of our own it became desirable to know the dissociation constants of cysteine, thioglycollic acid and thiolactic acid. It was thought worth while at the same time to determine the corresponding constants of cystine in order that a gap in the electrochemical data on the natural amino-acids might be filled.