Homochiral and Heterochiral Assemblies of 3 ₁₀ ‐helical 1‐aminocyclopropane‐1‐carboxylic Acid Foldamers in the Crystals

Abstract X‐ray crystallographic analysis unambiguously revealed the molecular conformations, packing structures, and intermolecular interactions of homo‐oligopeptide foldamers constructed from achiral 1‐aminocyclopropane‐1‐carboxylic acid (Ac 3 c). The conformational properties of these Ac 3 c homo‐oligopeptides, Mts‐(Ac 3 c) n ‐OR (Mts = 2‐mesitylenesulfonyl) 1 – 3 , enabled the formation of distorted 3 10 ‐helical foldamers stabilized by intramolecular hydrogen bonds. In the crystalline state, left‐handed ( M ), and right‐handed ( P ) 3 10 ‐helical Ac 3 c foldamers assembled into linear networks through head‐to‐tail intermolecular hydrogen bonds. These networks were organized into two types: homochiral sequences ( ···M···M···M··· and ···P···P···P·· ·) and heterochiral sequences (· ··M···P···M···P··· ).