Novel alkenyl substituted aryl bicyclic furano pyrimidines have been prepared and evaluated in vitro against Varicella Zoster Virus (VZV). The para-substituted analogues retain the nanomolar potency we have reported for p-alkyl analogues, while the ortho- and meta- alkenyl systems lose 3-4 orders of potency. Crown Copyright (C) 2009 Published by Elsevier Ltd. All rights reserved.