RESUMO
A series of thirty-three alkynyl and ß-ketophosphonates were evaluated for their in vitro acetyl- and butyryl-cholinesterase (AChE and BChE) inhibitory activities using Ellman's spectrophotometric method. None of the examined compounds inhibited AChE activity at tested concentrations while twenty-nine of them showed significant and selective inhibition of BChE with IC50 values between 38.60⯵M and 0.04⯵M. In addition, structure-activity relationships were discussed. The most effective inhibitors were the dibutyl o-methoxyphenyl alkynylphosphonate 3dc and dibutyl o-methoxyphenyl ß-ketophosphonate 4dc. Activities of most potent compounds were also compared with a commercial organophosphorus compound. These results could inspire the design of new inhibitors with stronger activity against BChE.