The present invention relates to pharmaceutical compositions for the treatment or prevention of viral infections comprising as an active principle at least one compound having the general formula (A): wherein U is N or C; X is selected from C1-C10 alkylene, C2-10 alkenylene or C2-10 alkynylene, where each may include one or more intrachain heteroatoms selected from O, S, or NR11, provided any such heteroatom is not adjacent to the N in the ring; R3 is selected from aryl, aryloxy, arylthio, cycloalkyl, cycloalkenyl, cycloalkynyl, aryl-N(R10)—, or heterocycle, where each said substituent is optionally substituted with at least one R17, provided that for cycloalkenyl the double bond is not adjacent to a nitrogen; and the other substituents are described in the specification. The invention also relates to processes for the preparation of compounds according to the invention having above mentioned general formula, their pharmaceutically acceptable formulations and their use as a medicine or to treat or prevent viral infections.