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Updated: May 10, 2026
14:18
A Strategy for Sensitive, Large Scale Quantitative Metabolomics
Published on: May 27, 2014
l-Leucylglycylglycine
Masanori Ootaki1, Yukino Nawa, Tomoko Hiroi
1Institute of Radioisotope Research, St. Marianna University Graduate School of Medicine, 2-16-1 Sugao, Miyamae-ku, Kawasaki, Kanagawa 216-8511, Japan.
Summary
This study details the zwitterionic crystal structure of a compound, revealing a folded main chain stabilized by extensive hydrogen bonding and hydrophobic interactions, forming a unique three-dimensional network.
Area of Science:
- Crystallography
- Molecular structure analysis
- Supramolecular chemistry
Background:
- Understanding the solid-state behavior of amino acid derivatives is crucial for drug design and materials science.
- Zwitterions, molecules with both positive and negative charges, exhibit unique intermolecular interactions.
- The specific compound investigated provides insights into the interplay of charged termini and side chains in crystal packing.
Purpose of the Study:
- To elucidate the crystal structure of the title compound (C10H19N3O4).
- To characterize the intermolecular interactions, including hydrogen bonding and hydrophobic interactions, within the crystal lattice.
- To describe the overall molecular conformation and network formation in the solid state.
Main Methods:
- Single-crystal X-ray diffraction was employed to determine the three-dimensional molecular structure.
- Analysis of hydrogen bonding networks, including N-H···O and C-H···O interactions.
- Identification of hydrophobic regions formed by side chains.
Main Results:
- The compound exists as a zwitterion in the crystal, with protonated N-termini and ionized C-termini.
- The main molecular chain adopts a folded conformation.
- A robust three-dimensional network is formed through hydrogen bonding between the N-terminal ammonium groups and C-terminal carboxylate groups, as well as carbonyl oxygen atoms.
- Intramolecular hydrogen bonds involving amide groups and C-H···O interactions contribute to the crystal structure along the a-axis.
- Leucyl side chains create a distinct hydrophobic region extending along the a-axis.
Conclusions:
- The crystal structure reveals a complex interplay of electrostatic, hydrogen bonding, and hydrophobic forces dictating the solid-state arrangement.
- The zwitterionic nature and folded conformation are stabilized by a well-defined hydrogen bond network.
- The segregation of hydrophobic side chains suggests potential implications for molecular recognition and self-assembly processes.
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