Solid-State Conformational Flexibility at Work: Energetic Landscape of a Single Crystal-to-Single Crystal Transformation in a Cyclic Hexapeptoid.

ABSTRACT: We describe the energetic landscape beyond the solid-state dynamic behavior of a cyclic hexapeptoid decorated with four propargyl and two methoxyethyl side chains, namely, cyclo-(Nme-Npa₂)₂, Nme = N-(methoxyethyl)glycine, Npa = N-(propargyl)glycine. By increasing the temperature above 40 °C, the acetonitrile solvate form 1A starts to release acetonitrile molecules and undergoes a reversible single crystal-to-single crystal transformation into crystal form 1B with a remarkable conformational change in the macrocycle: two propargyl side chains move by 113° to form an unprecedented "CH-π zipper". Then, upon acetonitrile adsorption, the "CH-π zipper" opens and the crystal form 1B transforms back to 1A. By conformational ene

SUBMITTER: Pierri G 

PROVIDER: S-EPMC7877721 | biostudies-literature | 2021 Feb

REPOSITORIES: biostudies-literature