PCILO STUDIES ON ANTI-AIDS AGENTS - CONFORMATION OF DDG AND DDAPR

Conformational preferences of two anti-AIDS agents: 2',3'-dideoxyguano sine (ddG) and 2',3'-dideoxy-2,6-diaminopurine riboside (ddAPR) have b een investigated by using the semi-empirical quantum mechanical PCILO method. The computations have been carried on these anti-AIDS agents h aving both C2'-endo and C3'-endo sugar puckers as well as their respec tive parent molecules, guanosine (G) and 2,6-diaminopurine riboside (A PR). The results obtained exhibit a remarkable similarity in the confo rmation of these anti-AIDS agents and their parent nucleosides. The im portant biological significance of this result has been discussed in t he light of our earlier results on the conformation on azidothymidine (AZT) which is the most widely used anti-AIDS drug throughout the worl d.