| abstract |
Compounds of the general formula <CHEM> (wherein X is sulphur or oxygen or a chemical bond; R<1> is halogen, amino or azido; R<2> is hydrogen, hydroxy, alkyl or hydroxyalkyl; R<3> is hydrogen or alkyl; R<4> is hydroxy, hydroxyalkyl, benzyloxy, phosphate or carboxypropionyloxy; R<5> is hydrogen, alkyl or hydroxyalkyl) and salts and esters thereof, have been found to have valuable antiviral activity particularly against herpes viruses. Methods for the preparation of the above compounds are described as well as pharmaceutical formulations containing such compounds. |