Photoresponsive dendritic azobenzene peptides

Two dendritic peptides containing a branched lysine core and up to eight az obenzene moieties in the periphery were synthesized on solid support employ ing the omega -amino acid 4-(aminomethyl)phenylazobenzoic acid. With an add itional peptidic tail consisting of an oligolysine portion, water solubilit y was achieved for the dendrimers, which allowed for the characterization o f the cis/trans photoisomerization of the dendritic azobenzene species in b oth organic and aqueous media. Despite the interactions between the chromop hores, which occur particularly in. aqueous, media, at higher dilution the photoisomerization process was found to. proceed to extents that should per mit photomodulation of molecular recognition processes between ligands graf ted to the photosensitive azobenzene units and receptor molecules.