Fig. 3.
Conformational free energy landscapes of N-aryl peptoid trimer 1 and N-alkyl peptoid trimer 2. Landscapes calculated from REMD simulations show a funnel-like landscape for 1, with a small number of low free energy torsional states. The observed crystal structure of 1 is found at the free energy minimum of this landscape (black arrow). The landscape of 2 is more degenerate, suggesting a more heterogeneous structure in solution. The crystal structure observed for 2 (red arrow) is estimated by REMD to be approximately 2.5 kcal/mol above the solution-phase ground state.