A series of isomeric 2',3'-dideoxynucleosides which contains a modified carbohydrate moiety has been prepared. This class of compounds was designed to mimic the activity of known anti-HIV dideoxynucleosides, while imparting enhanced chemical and enzymatic stability. Isonucleosides containing the standard heterocyclic bases (A, C, G, T) were synthesized via nucleophilic addition of the base to an isomeric sugar unit. Modified derivatives were generated by manipulation of the intact isonucleoside. Two of the compounds prepared, iso-ddA (1) and iso-ddG (6), exhibit significant and selective anti-HIV activity, as well as beneficial hydrolytic stability.
Novel isomeric dideoxynucleosides as potential antiviral agents
摘要:
Novel isomeric dideoxynucleosides with S,S absolute stereochemistry and involving the transposition of the base moiety from the normal 1'- to the 2'-position have been regiospecifically and stereospecifically synthesized. The synthetic approaches involved either direct coupling with inversion at the 2-position of a preformed dideoxygenated sugar using the base moiety as nucleophile (for purine isodideoxynucleosides) or construction of the base moiety onto a stereochemically defined amino sugar precursor (pyrimidine isodideoxynucleosides). These compounds possess extremely high stability with respect to ''glycosidic'' bond cleavage and enzymatic deamination. Antiviral data suggest that the most active compound was levorotatory S,S-isodideoxyadenosine.