Novel enzymatic de-esterification studies on substituted polyacetoxybenzamides

The regioselective capabilities of porcine pancreatic lipase in tetrahydrof uran and Candida rugosa lipase in diisopropyl ether have been investigated for selective deacetylation of peracetates of primary, secondary and tertia ry amides of 2-hydroxy-, 2,4-dihydroxy-, 2,5-dihydroxy-, 3,5-dihydroxy- and 3,4,5-trihydroxybenzoic acids. The lipases exhibit random selectivity for the deacetylation of ortho-, meta- and para-acetoxy functions of di/triacet oxybenzamides leading to the formation of the corresponding partially and/o r completely deacetylated benzamides. The am ide group of all substrates un der investigation remains inert to enzymatic hydrolysis. The results of de- esterification are in good agreement with our earlier proposed mechanism of action of porcine pancreatic lipase on diaryl or aryl allyl ketones in org anic solvents.