title: Acetylcholinesterase inhibition by sulphur and selenium heterosubstituted isomers of N,N-diethylcarbamyl choline and carbaryl.
abstract: Nine sulphur and selenium heterosubstituted isomers of N,N-diethylcarbamylcholine and carbaryl have been prepared and their inhibiting activity towards electric eel acetylcholinesterase (E.C. 3.1.1.7) have been measured. The N,N-diethylcarbamylcholines acted only as reversible inhibitors, i.e. they could not carbamylate the enzyme. The reversible inhibition was of mixed type. Sulphur and selenium substitution had only marginal effects on Ki(0.2-0.3 mM) but reduced the value of K'i. The heterosubstituted carbaryl analogues were, with one exception, found to be irreversible inhibitors, about 100 times less potent than carbaryl.
mesh_terms: D000818:Animals; D002219:Carbamates / Q000138:chemical synthesis* / Q000494:pharmacology; D012721:Carbaryl / Q000031:analogs & derivatives* / Q000138:chemical synthesis* / Q000494:pharmacology; D002800:Cholinesterase Inhibitors / Q000138:chemical synthesis* / Q000494:pharmacology; D004593:Electrophorus; D007202:Indicators and Reagents; D007700:Kinetics
chemical_list: D002219:Carbamates; D002800:Cholinesterase Inhibitors; D007202:Indicators and Reagents; D012721:Carbaryl