Figure 5.
Dimer and tetramer of peptide 1b. Hydrogen-bonded dimer subunit (upper). Red arrows illustrate intramolecular and intermolecular NOEs observed in the NOESY spectrum. Sandwich-like tetramer consisting of two hydrogen-bonded dimers (lower). The red arrow illustrates the interlayer NOEs observed in the NOESY spectrum. The tetramer exhibits four-fold symmetry and four I11–HaoOMe interactions, even though only one arrow is shown.