Ribose conformations of 8-azapurine nucleosides in solution.
نویسندگان
چکیده
The ribose conformations of 8-azaadenosine, 8-azaguanosine, and 8-azainosine have been studied using proton magnetic resonance in ND3 solutions, in D2O solutions, and in pyridine solutions. The temperature was varied between -60 and +40 degrees C in ND3 and between +10 and +60 degrees C in D20 solutions. The analysis is based on the two state S in equilibrium N model of the ribose moiety proposed by Altona and Sundaralingam. In D2O, the 8-aza substitution destabilizes the gg rotamer and simultaneously diminishes the population of the S state of the ribose. It is deduced that the anti population of the base is greater in the 8-azapurine(beta)ribosides than in the common purine(beta)-ribosides.
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ورودعنوان ژورنال:
- Zeitschrift fur Naturforschung. Section C, Biosciences
دوره 31 3-4 شماره
صفحات -
تاریخ انتشار 1976