Remaud G, Zhou X X, Chattopadhyaya J, Oivanen M, Lönnberg H
Department of Bio-organic Chemistry, University of Uppsala, Sweden.
Nucleic Acids Symp Ser. 1987(18):145-8.
Kinetics for the acidic hydrolysis of several N6-substituted 2'-deoxyadenosines were studied in a wide pH-range. The proportions of the partial reactions proceeding via mono- and di-protonated substrates were estimated on the bases of the rate profiles obtained and the acidity constants determined spectrophotometrically for the monocations. The site of the initial protonation was established by the effects that trifluoroacetic acid exerted on the 15N NMR chemical shifts. The exceptional lability of the monocations of N6-acyl protected compounds is suggested to result from the preferred N7 protonation.
在很宽的pH范围内研究了几种N6-取代的2'-脱氧腺苷酸催化水解的动力学。根据所获得的速率曲线和通过分光光度法测定的单阳离子酸度常数，估算了通过单质子化和双质子化底物进行的部分反应的比例。通过三氟乙酸对15N NMR化学位移的影响确定了初始质子化的位点。N6-酰基保护化合物的单阳离子具有异常的不稳定性，这被认为是由优先的N7质子化导致的。
