Abstract
Modifying the backbone of 24-atom macrocycles allows tailoring of physical properties (octanol-water partition coefficients, log P) while conserving both conformation and the barrier to dynamic, hinge-like motion. Structure is determined by 1D and 2D NMR spectroscopy. The barrier can be subtly tuned by modifications that appear to preclude fully revolute motion and efficient π-stacking of the two subunits. The log P values increase as expected across this series, and the correlation between computed and observed values reinforces the belief of common structure and behavior across this class of macrocycles.