Synthesis and anticholinesterase activity of S-alkynyl diethyl thiophosphates containing hydrophobic or onium groups in the alkylthiol radical

A study has been carried out of the anticholinesterase activity of S-alkynyl dialkyl thiophosphates containing hydrophobic or onium groups in the thioalkyl radical. It has been shown that interaction of the acetylenic bond with the corresponding region of the enzyme is not in accordance with the hydrophobic interaction of the thioalkyl radical. The presence of an acetylenic bond in the onium compounds results in a decrease in their inhibitory activity as compared with the analogous uncharged compounds.