| Abstract
| - Heterocyclic unit 2 containing complementary donor−donor−acceptor (DDA) and acceptor−acceptor−donor (AAD) hydrogen bonding arrays at an angle of about 60° was designed to self-assembleinto a hexamer. To investigate whether this unit could self-assemble dendrimers, the 2,8-diamino-2-N-ethylpyrimido-(4,5-b)(1,8)naphthyridine-3H-4-one subunit was synthesized with a first (2a), second (2b),and third generation (2c) Fréchet-type dendron attached to the 8-amino group. The synthesis of 2a−cwas accomplished in 11 steps beginning with 2,6-diaminopyridine and the corresponding dendron bromide.Studies using 1H NMR, size exclusion chromatography (SEC), and dynamic light scattering (DLS) supportthe cooperative formation of cyclic hexamers in apolar solvents. The stability of the self-assembleddendrimers is dependent on the size of the attached dendron, and mixing studies with 2a−c indicate theirusefulness in constructing dynamic combinatorial libraries.
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