INHIBITION REVERSIBLE DE LA BUTYRYLCHOLINESTERASE PAR QUELQUES PHOSPHORAMIDES ALIPHATIQUES

Syntheses and spectroscopic characterization of some phosphoramidates as reversible inhibitors of human acetylcholinesterase and determination of their potency

The ability of phosphoramidates Me2NP(O)(Cl)(p-NHC6H4NO2) 1, Me2NP(O)(p-NHC6H4NO2)2 2, (CH3C6H4O-p)P(O)(p-NHC6H4NO2)2 3 and (CH3C6H40-p)2P(O)(p-NHC6H4NO2) 4 to inhibit human acetylcholinesterase (hAChE) has been evaluated by a modified Ellman's method and spectrophotometric measurements. Results showed that compounds 1 and 2 do not have any inhibitory potency, whereas compounds 3 and 4 were reversible mixed inhibitors. The IC50 values for inhibitors 3 and 4 were 0.143 and 0.581 mM, respectively. The previously unknown compounds 3 and 4 were synthesized and characterized by 1H, 13C, 31P NMR and IR spectroscopy and elemental analysis.

Acetylcholinesterase inhibition by two phosphoric 4-nitroanilides

Two phosphoric 4-nitroanilides Z2P(O)NH-phi-NO2 (A, Z = Me; B, Z = NMe2) have been prepared and purified by chromatographic techniques. Their spectral data (uv, ir and 1H-nmr) have been determined, and compared with those of other similar compounds. Their ability to inhibit acetylcholinesterase has been measured by a modification of Ellman's method. The data, as computed according to the Michaelis scheme, indicate that A is not an inhibitor, whereas B is a reversible mixed one. These differences are discussed in terms of hydrophobic interactions.