Amphiphilic nucleoside phosphate analogues of formula I ##STR1## wherein R.sup.1 denotes a hydroxyl or amino group or an acylated or alkylated or polyoxyethylene-substituted amino group, the acyl or alkyl group of which is straight-chained or branched, has 1 to 24 carbon atoms and up to 2 double bonds and may be substituted by an aromatic group; R.sup.2 denotes H, F, a 2-bromo vinyl group or a straight-chained or branched C.sub.1-24 -alkyl group; R.sup.3 and R.sup.4 are identical or different and denote H, hydroxyl, halogen and azido; R.sup.5 denotes a nucleoside group of formula II ##STR2## wherein R.sup.6 denotes a hydroxyl or amino group or an acylated or alkalized amino group, the acyl or alkyl group of which is straight-chained or branched, contains 1 to 24 carbon atoms and up to 2 double bonds and may be substituted by an aromatic group, whilst R.sup.6 and R.sup.1 are different and one of the groups denotes acylamino or alkylamino groups having 12 to 24 carbon atoms, R.sup.1, R.sup.2, R.sup.6 and R.sup.7 are selected so that, together, they impart an amphiphilic nature to a dinucleotide phosphate analogue; and the corresponding salts of the acid forms of these compounds.