Density function of 3′-azido-3′-deoxythymidine

The internal rotation potential energy curve around the glycosidic bond in 3′-azido-3′- deoxythymidine (AZT) molecule, an HIV-1 reverse transcriptase inhibitor, is calculated by using density functional B3LYP method and a 3–21G basis set. For the stationary points along the internal rotation energy curve, the B3LYP/6–31G* full geometry optimization and frequency analysis calculations are performed. Along the curve there are two energy minima, one of which corresponds to a structure having a North conformation (P= 85.3°) and in the anti range (x= −129.1°) and the +sc range (y= 62.1°), which is consistent with the conformation of AZT in the AZT 5′- triphosphate bound to HIV RT.