Phenylacetate와 그 유도체의 acetylcholinesterase에의 한 hydrolysis 속도를 비교 측정하였다. Acetylcholine의 quaternary group과 같은 trimethylammonium을 o- 나 p-위치에 넣을경우 phenylacetates의 hydrolysis 속도는 빨라졌지만 m-위치에 trimethylammonium을 넣을경우 hydrolysis 속도는 매우 느려졌다. ter-butyl group은 cationic charge를 갖지 않은 trimethylammonium의 carbon analog 이지만 m-position에 넣은경우 hydrolysis 속도는 빨라졌다.
The hydrolysis rates of o-, m- and p-trimethylammonium phenylacetates by acetylcholinesterase were compared in relation with phenylacetate and m-ter butyl phenylacetate. o- or p-Trimethylammonium and m-ter butyl substitution gave favorable effect on the hydrolysis by the enzyme. However, the hydrolysis rate of phenylacetate was decreased with the m-trimethylammonium substitution which makes the compound most sterically resemble to acetylcholine, the natural substrate of acethylcholinesterase. It appears that trimethylammonium group increased the hydrolysis rate by the enzyme not by having electrostatic interaction with the anionic site of the enzyme but by stabilizing the phenoxy ion by electron attracting properties of the group.
