Marta M, Gatta F, Pomponi M
Istituto di Chimica, U.C.S.C. Facoltà di Medicina A. Gemelli, Rome, Italy.
Biochim Biophys Acta. 1992 Apr 17;1120(3):262-6. doi: 10.1016/0167-4838(92)90246-a.
Data are presented about the inhibitor power of new carbamates against acetylcholinesterase. The study was carried out on two series of physostigmine analogs, N-alkyl and N-methyl,N-alkylphysostigmines. For these inhibitors, the second-order rate constants for inhibition, ki, and the first-order rate constants of reactivation, k3, have been determined. From the reported results, electronic, hydrophobic and steric effects, due to the enhancement of the alkyl chain, may have influenced all kinetics parameters discussed. In comparison to physostigmine, both the new N-methyl,N-alkylphysostigmines and the N-alkylphysostigmines showed a non-linear decrease in the values of ki and k3. This study presents the hydrophobic interactions as an important factor not only in determining carbamylation but also decarbamylation rates constants.
文中给出了新型氨基甲酸酯对乙酰胆碱酯酶抑制能力的数据。该研究针对毒扁豆碱的两类类似物展开，即N-烷基毒扁豆碱和N-甲基-N-烷基毒扁豆碱。对于这些抑制剂，已测定了抑制反应的二级速率常数ki和复活反应的一级速率常数k3。从报告结果来看，由于烷基链的增长所产生的电子、疏水和空间效应，可能对所讨论的所有动力学参数都产生了影响。与毒扁豆碱相比，新型N-甲基-N-烷基毒扁豆碱和N-烷基毒扁豆碱的ki和k3值均呈非线性下降。本研究表明，疏水相互作用不仅是决定氨甲酰化反应的重要因素，也是决定脱氨甲酰化反应速率常数的重要因素。
