Computational Chemistry and Molecular Modeling
Atomic, Molecular and Optical Physics
Wiley InterScience Backfile Collection 1832-2000
Chemistry and Pharmacology
The influence of accepting the hydrogen bond by N(3) of adenine on the conformational preferences of the N(6) substituent in modified nucleic acid base N6-(N-glycylcarbonyl)adenine (gc6Ade) has been modeled by the protonation of N(3). The preferred orientation of the glycylcarbonyl substituent changes on the protonation of N(3). The preferred conformation for the N(3) protonated base is the planar, intramolecular bifurcated hydrogen-bonded structure involving the interaction of the ureido N(11)H with the N(1) of the purine and the O(13b) of the amino acid carboxyl. Another conformation of nearly equal stability, having the internal hydrogen bonding of O(13b) with the N(6)H, is also predicted. Such protonation or hydrogen-bonding-induced conformational flipping may enable the structural reorientation of the anticodon loop required for the functioning of tRNA. © 1994 John Wiley & Sons, Inc.
Type of Medium: