Synthesis of novel racemic carbocyclic nucleoside analogues derived from 4,8-dioxatricyclo[4.2.1.03,7]nonane-9-methanol and 4-oxatricyclo[4.3.1.03,7]decane-10-methanol, compounds with activity against Coxsackie viruses

Abstract

(1R*,2R*,3R*,4S*)-7-Oxabicyclo[2.2.1]hept-5-ene-2,3-dimethanol (10) and (1R*,2R*,3R*,4S*)-bicyclo[2.2.2]oct-5-ene-2,3-dimethanol (14), which were prepared by the Diels–Alder reaction and subsequent reduction with lithium aluminium hydride, were treated with benzyl azidoformate to give benzylN-[(1R*,2R*,3S*,6S*,7S*,9S*)-9-(hydroxymethyl)-4,8-dioxatricyclo[4.2.1.03,7]nonan-2-yl]carbamate (11) and benzylN-[(1R*,2R*,3R*,6R*,7S*,10S*)-10-(hydroxymethyl)-4-oxatricyclo[4.3.1.03,7]decan-2-yl]carbamate (15). Hydrogenolysis of carbamates11or15afforded (1R*,2R*,3S*,6S*,7S*,9S*)-2-amino-4,8-dioxatricyclo[4.2.1.03,7]nonane-9-methanol (12) or (1R*,2R*,3R*,6R*,7S*,10S*)-2-amino-4-oxatricyclo[4.3.1.03,7]decane-10-methanol (16). The amines12and16were transformed to thymine and purine nucleoside analogues. The target compounds were tested for the activity againstCoxsackievirus.