Atomic-resolution structure analysis inside an adaptable porous framework

Area of Science:

• Materials Science
• Supramolecular Chemistry
• Crystallography

Background:

• Metal-organic frameworks (MOFs) offer tunable porous structures for molecular encapsulation.
• Ordered internal water networks within MOFs can mediate guest interactions.
• Structural elucidation of complex molecules often requires precise crystallographic methods.

Purpose of the Study:

• To develop a versatile MOF for guest encapsulation and immobilization.
• To utilize a water-mediated entrapment mechanism for structural elucidation of bioactive compounds.
• To investigate the role of host-solvent-guest interactions in molecular alignment within MOF pores.

Main Methods:

• Synthesis of a novel metal-organic framework (MOF).
• Encapsulation of 14 bioactive compounds, including natural product intermediates.
• Single-crystal X-ray diffraction analysis for structural determination.
• Computational analysis of host-solvent-guest interactions.

Main Results:

• The MOF effectively encapsulates diverse guests via a water-mediated mechanism.
• Three-dimensional structures of 3 natural product intermediates were successfully elucidated.
• Hydrogen-bonded water networks within the MOF pores adapt to guest molecules.
• Weak dispersion forces dominate guest-MOF interactions, while hydrogen bonds provide directional alignment.

Conclusions:

• The developed MOF provides a versatile platform for guest encapsulation and structural analysis.
• The water-mediated entrapment mechanism is effective for clarifying the structures of complex bioactive molecules.
• Understanding host-solvent-guest interactions is crucial for designing MOFs with controlled guest alignment.