Ponomar'ova A G, Iurenko Ie P, Zhurakovs'kyĭ R O, Govorun D M
Ukr Biokhim Zh (1999). 2012 Jan-Feb;84(1):67-78.
Comprehensive conformational analysis of the biologically active nucleoside 2',3'-didehydro-2',3'-dideoxyaguanosine (d4G) has been performed at the MP2/6-311++G(d,p)//DFT B3LYP/6-31G(d,p) level of theory. The energetic, geometrical and polar characteristics of twenty d4G conformers as well as their conformational equilibrium were investigated. The electron density topological analysis allowed us to establish that the d4G molecule is stabilized by nine types of intramolecular interactions: O5'H...N3, O5'H...C8, C8H...O5', C2'H...N3, C5'H1...N3, C5'H2...N3, C8H...H1C5', C8H...H2'C5' and N2H1...O5'. The obtained results of conformational analysis permit us to think that d4G may be a terminator of the DNA chain synthesis in the 5'-3' direction. Thus it can be inferred that d4G competes with canonical 2'-deoxyaguanosine in binding an active site of the corresponding enzyme.
已在MP2/6 - 311++G(d,p)//DFT B3LYP/6 - 31G(d,p)理论水平上对生物活性核苷2',3'-二脱氢-2',3'-二脱氧鸟苷（d4G）进行了全面的构象分析。研究了二十种d4G构象异构体的能量、几何和极性特征及其构象平衡。电子密度拓扑分析使我们能够确定，d4G分子通过九种分子内相互作用得以稳定：O5'H...N3、O5'H...C8、C8H...O5'、C2'H...N3、C5'H1...N3、C5'H2...N3、C8H...H1C5'、C8H...H2'C5'和N2H1...O5'。构象分析所得结果使我们认为，d4G可能是5'-3'方向DNA链合成的终止剂。因此可以推断，d4G在结合相应酶的活性位点时会与典型的2'-脱氧鸟苷竞争。
