The coordination behavior of N-tosyl-L-glutamine (hereafter abbreviated as tsglnH, tosyl = toluenesulfonyl group) toward the Zn(II) ion is investigated by means of structural and spectroscopic techniques. From aqueous solution, at acidic pH the Zn(II) ion separates a compound of empirical formula Zn(tsgln)(2) . 2H(2)O whose crystal structure is determined. The crystal is monoclinic, space group C2, with cell dimensions: a = 19.775(5), b = 5.3146(3), c = 16.543(8)Angstrom, beta = 119.93(3)degrees, Z = 2. The Zn(II) is tetrahedrally coordinated by two symmetry-related tsgln monoanions acting as monodentate carboxylate Ligands and two symmetry related water molecules. The Zn-O bond distances are similar while the angles at Zn(II) ion differ significantly from those of regular tetrahedron. The side chain amide group does not participate in metal coordination and forms intermolecular hydrogen bonds.
Coordination properties of sulfonyl-N-aminoacids: Crystal and molecular structure of the [Zn(II)(N-(p-toluenesulfonyl)-L-glutaminate)(2)(H2O)(2)] complex / Lusvardi, Gigliola; Menabue, Ledi; Saladini, Monica. - In: JOURNAL OF CHEMICAL CRYSTALLOGRAPHY. - ISSN 1074-1542. - STAMPA. - 25(11):(1995), pp. 713-716.