Novel lipoamino acid- and liposaccharide-based system for peptide delivery: Application for oral administration of tumor-selective somatostatin analogues

Lipoamino acid and liposaccharide conjugates of somatostatin analogue TT-23 2 were synthesized to modify the physicochemical properties of the parent p eptide. The relative position, the number, and the nature of the lipid and/ or saccharide moieties were varied. Experiments in vitro clearly showed tha t many compounds modified at the N- and/or C-terminus with lipid or sugar m oieties retained the biological activity of the parent compound. An interes ting construct was synthesized containing lipid and sugar units at opposite ends of the somatostatin analogue, so that the entire molecule could be co nsidered as an amphipathic surfactant.