In recent years, we have prepared a series of oligoindoles that fold into helical structures
upon anion binding. The molecular building block of a biindole unit exists in a transoid
conformation to minimize dipole-dipole repulsions between two indole units. As the
consequence, the oligoindoles display an extended zigzag-shaped conformation. Herein, we
have prepared new oligoindoles with the amide and urea functional groups at the ends of the
strand. These groups form intramolecular hydrogen bonding with the indole NH protons,
which may enables the folding of the oligomers in a helical conformation. Furthermore, the
oligoindoles contain an internal cavity capable of binding a complementary guest, e.g. anions.
Details including the features of folding structures and the properties of anion binding will be
described in the poster.