A Comparison of the Reactivity and Mutagenicity of <i>N</i>-(Benzoyloxy)-<i>N</i>-(benzyloxy)benzamides
作者:Stephen A. Glover、Gerard P. Hammond、Antonio M. Bonin
DOI:10.1021/jo980863z
日期:1998.12.1
A new series of N-(acyloxy)-N-alkoxybenzamides, N-(benzoyloxy) -N-(benzyloxy)benzamides 7 have been synthesized and have been found to be direct acting mutagens in Salmonella TA100. They undergo A(Al)1 solvolysis to give N-benzoyl-N-(benzyloxy)nitrenium ions 3 under conditions of acid catalysis as well as unusual B(Al)2 reactions at nitrogen with hydroxide. The latter process affords as intermediates the anomeric hydroxamic esters 4 which rearrange intramolecularly to esters in a HERON reaction. Rates of acid-catalyzed solvolysis and reaction with hydroxide ions correlate with Hammett a values with low sensitivity (rho = +0.32 and +0.55, respectively) in accordance with the A(Al)1 and B(Al)2 mechanisms. Mutagenicity for the series also appears to correlate with Hammett sigma values but with low, negative sensitivity (rho = -0.57), and their biological activity may be attributable to their stability under conditions of the Ames assay and hydrophobic binding to DNA, rather than their chemical reactivity.