Dendrimers are well-defined, highly branched macromolecules that emana
te from a central core and are synthesized through a stepwise, repetit
ive reaction sequence. The synthesis and characterization of dendritic
boxes, based on the construction of a chiral shell of protected amino
acids onto poly(propyleneimine) dendrimers with 64 amine end groups,
is reported here. Nuclear magnetic resonance-relaxation and optical da
ta show that a dense shell with solid-phase character is formed. Guest
molecules were captured within the internal cavities of the boxes whe
n these boxes were constructed in the presence of guest molecules. The
diffusion of guest molecules out of the boxes into solution was unmea
surably slow because of the close packing of the shell. These monomole
cular dendritic containers of 5-nanometer dimensions with physically l
ocked-in guest molecules were characterized spectroscopically.