CHARACTERISTICS OF INHIBITION OF BUTYRYL CHOLINESTERASE AND CARBOXYL ESTERASE HYDROLYSIS BY BETA,BETA-DIPHENYLETHYLPHOSPHONIC ACID FLUOROANHYDRIDE ESTERS

A new series of organophosphorus compounds, beta,beta-diphenylethylpho sphonic acid fluoroanhydride esters with various alkyl radicals (CH3, C2H5, C3H7, iC(3)H(7), C4H9, i-C4H9, C5H11, and C6H13) and phenyl radi cal C6H5, were tested for inhibition of horse serum butyryl cholineste rase (EC 3.1.1.8) and of two forms of reindeer liver carboxyl esterase (EC 3.1.1.1). All the tested compounds are strong irreversible inhibi tors of butyryl cholinesterase and strong combined-type inhibitors of carboxyl esterase. The inhibition constants were found to depend on th e structure of the alkyl radical in the inhibitor molecule.