Synthesis and Antiviral Activity of 9-purines

Article abstract of DOI:10.1021/jm00392a020

Alkylation of 2-amino-6-chloropurine with 5-(2-bromoethyl)-2,2-dimethyl-1,3-dioxane (5) provided 2-amino-6-chloro-9-<2-(2,2-dimethyl-1,3-dioxan-5-yl)ethyl>purine (6) in high yield.This aminochloropurine 6 readily converted to the antiviral acyclonucleoside 9-<4-hydroxy-3-(hydroxymethyl)but-1-yl>guanine (1) and to its 6-chloro (10), 6-thio (11), 6-alkoxy (12-17), 6-amino (20), and 6-deoxy (21) purine analogues.The guanine derivative 1 was converted to its xanthine analogue 9.Similarly, alkylation of 6-chloropurine with 5 provided a route to 8, the hypoxanthine analogue of 1.Of these 9-substituted purines, the guanine derivative 1 showed the highest activity against herpes simplex virus types 1 and 2 in cell cultures, and in some tests it was more active than acyclovir, with no evidence of toxicity for the cells.A series of monoesters (30-33) and diesters (24-27, 29) of 1 were prepared, and some of these also showed antiherpes virus activity in cell cultures, the most active ester being the dihexanoate 27.