Keywords: Nucleosides / Amphiphiles / Lipophilicity / Membrane anchoring / Synthesis Nucleosides were synthesized bearing one or two lipophilic groups at the 5Ј-position. The lipophilic substituents can be fixed at a 5Ј-amino group or at the 5Ј-phosphate moiety. Selected examples of these lipophilic nucleosides are shown by