The Journal of Organic Chemistry

First-order rate constants for the racemization of each component in a mixture of isomeric dipeptides and their diketopiperazine

GG Smith, R Baum

Index: Smith, Grant Gill; Baum, Rocky Journal of Organic Chemistry, 1987 , vol. 52, # 11 p. 2248 - 2255

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Citation Number: 23

Abstract

L-Alanylglycine (L-Ala-Gly), glycyl-L-alanine (Gly-L-Ala), and cL-Ala-Gly [diketopiperazine (DKP)] were racemized at 120" C in aqueous phosphate-buffered solutions at pH 8.0, a pH value near maximum racemization. The kinetics were followed by regression analysis. The racemization of Ala-Gly and Gly-Ala closely followed reversible first-order kinetics. The initial rate of racemization of DKP was fast but soon slowed, likely because of hydrolysis to the ...