N, O-Dicarbethoxy-4-chlorobenzenesulfohydroxamate (IC) and 0-carbethoxy-N- hydroxysaccharin (61, both potential carbethoxylating agents, inhibited yeast aldehyde dehydrogenase (AlDH) with Ic50) s of 24 and 56 pM, respectively. The esterase activity of the enzyme was commensurably inhibited. AlDH activity was only partially restored on incubation with mercaptoethanol (20 mM) for 1 h. On incubation with rat plasma, IC ...