The goal of this paper is the development of a “new” class of sensors that use selective chemically amplified toxic signatures (CATS) to detect pollutants in air. Most detection methods measure one molecule of product per analyte molecule. Our goal is to use catalyst poisoning to detect the presence or absence of thousands of product molecules per molecule of analyte. One example of this is the detection of toxic sulfur compounds and their simulants. Toxic sulfur compounds selectively bind to 4-(4'-nitrobenzyl) pyridine (DB-3) and its analogues. Also, DB-3 analogues have been used as effective acylation catalysts for the esterification of methanol to methyl acetate. Combining these two chemistries will allow us to chemically amplify the signal from one molecule of simulant by electrochemically monitoring methanol oxidation current. The goal of this work is to optimize the chemistry of the reaction by varying solvent, solution additives, and pyridine catalyst in order to chemically amplify the signal from one molecule of toxic sulfur compound.