The synthesis of four 5’-chain-extended adenosine derivatives is described. Threeof these nucleosides were prepared by manipulation of lactone 6, which is derived from N-benzoyl-2',3’-0-isopropylideneadenosine 5’-aldehyde by chain extension through Wittig chemistry. Functional group manipulation allowed introduction of the C-6’ amide and amine groups, and the chain terminal amino or hydroxyl group. The fourth compound was prepared in five steps from the natural product sinefungin. Antiviral data and certain enzyme inhibition data are presented on the target compounds. © 1990, Taylor & Francis Group, LLC. All rights reserved.