title: Graphene-like nets of hydrogen-bonded water molecules in the dihydrate of 2-[(2-ammonioethyl)amino]acetate and the structure of its anhydrous hydroiodide salt.
abstract: 2-[(2-Ammonioethyl)amino]acetate dihydrate, better known as N-(2-aminoethyl)glycine dihydrate, C(4)H(10)N(2)O(2) x 2 H(2)O, (I), crystallizes as a three-dimensional hydrogen-bonded network. Amino acid molecules form layers in the ac plane separated by layers of water molecules, which form a hydrogen-bonded two-dimensional net composed of fused six-membered rings having boat conformations. The crystal structure of the corresponding hydroiodide salt, namely 2-[(2-ammonioethyl)ammonio]acetate iodide, C(4)H(11)N(2)O(2)(+) x I(-), (II), has also been determined. The structure of (II) does not accommodate any solvent water molecules, and displays stacks of amino acid molecules parallel to the a axis, with iodide ions located in channels, resulting in an overall three-dimensional hydrogen-bonded network structure. N-(2-Aminoethyl)glycine is a molecule of considerable biological interest, since its polyamide derivative forms the backbone in the DNA mimic peptide nucleic acid (PNA).
authors.affiliation: Department of Physics and Chemistry, University of Southern Denmark, Campusvej 55, 5230 Odense M, Denmark.
authors.forename: Tove
authors.initials: T
authors.lastname: Wiklund
authors.forename: Christine J
authors.initials: CJ
authors.lastname: McKenzie
authors.forename: Anders
authors.initials: A
authors.lastname: Lennartson
mesh_terms: D018360:Crystallography, X-Ray; D005998:Glycine / Q000031:analogs & derivatives* / Q000737:chemistry; D006860:Hydrogen Bonding; D007477:Ions / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D012492:Salts / Q000737:chemistry*; D014867:Water
chemical_list: D007477:Ions; D012492:Salts; D014867:Water; C028791:N-(2-aminoethyl)glycine; D005998:Glycine