SYNTHESIS OF RACEMIC 5-SUBSTITUTED 1-(2,3-DIHYDROXYPROPYL)-6-AZAURACILS AND THEIR ISOSTERIC ISOMERS

Acyclic nucleoside analogues of antiviral DHPA and HPMPA have been pre pared. Coupling of silylated 6-azauracils with benzyl glycidyl. ether and stannic chloride followed by the deprotection with boron trichlori de gave 1-(2,3-dihydroxypropyl)-6-azauracils (3) in good overall yield s. Reaction of silylated 6-azauracil and epichlorohydrin with or witho ut catalytic stannic chloride afforded 1-(2-chloro-3-hydroxypropyl)-6- azauracil (4a) and 1-(3-chloro-2-hydroxypropyl)-6-azauracil (6a) respe ctively. Coupling of silylated 6-azaisocytosine under the same reactio n conditions provided 1-(2,3-dihydroxypropyl)-6-azaisocytosine (9) and 1-(2-chloro-3-hydroxypropyl)-6-azaisocytosine (10) respectively. None of the compounds exhibited significant antiviral activity against her pes simplex viruses.