pH Dependence of the rate of DNA alkylation for (+)-duocarmycin SA and (+)-CCBI-TMI

A study of the DNA alkylation rate pH dependence with the establishment of pseudo first-order rate constants for 1 and 3 at a single high affinity site in w794 DNA is detailed. This dependence proved to be remarkably small with the rates increasing only 1.89x and 2.5x, respectively, over 2 pH units (pH 6–8).