Use of O-p-Nitrobenzyl-N, N′-Diisopropylisourea as a Chromogenic Reagent for Liquid Chromatographic Analysis of Carboxylic Acids

O-p-Nitrobenzyl-N, N′-diisopropylisourea was shown to react under relatively mild conditions with carboxylic acids to yield the p-nitrobenzyl esters as chromogenic derivatives useful for liquid chromatographic analysis. The p-nitrobenzyl ester of stearic acid was detectable down to the picomole range.