The crystal structure of di(histidino)zinc pentahydrate

Abstract

The crystal structure of di(histidino)zinc pentahydrate, Zn(CsHsN30~)2.5H~O, has been determined by Fourier analysis and least-squares refinement using three-dimensional intensity data from CuKa radiation. The crystals are monoclinic, with space group C2/c, and cell dimensions a = 16.41, b = 14.755, c = 10.99 A, ~ = 129.6 °.The primary co-ordination around the zinc atoms, which lie on two-fold axes, is a distorted tetrahedron, consisting of an amino nitrogen and an imidazole nitrogen (at 2.05 and 2.00 A) from each of the two histidine groups. One oxygen atom from each histidine group is also very weakly associated (at 2.91 A). The molecules of di(histidino)zinc and the water molecules take part in an elaborate system of hydrogen bonds holding the structure together.Xext X (1-4-k~ ~/(sin 0') -~-K) Xco~t × (1--k~l/(sin 03+ K) # is one constant for all the data (=0.67 here), K are normalising constants in each layer, to make the correction zero at 0 = 90 °.After this spot-shape correction, all the data were correlated and assembled. The intensities of 1370 reflections were measured, those of 557 were too small for observation, and about 300 were not recorded on any film, although they are within the Cu K~ limit. An approximate scale and temperature factor were determined from a 'Wilson plot'.Sharpened Patterson projections along the b and c axes gave tentative positions for the zinc atoms, which were confirmed by the three-dimensional Patterson synthesis, sharpened 'to point atoms at rest'. The zinc atoms are on two-fold axes at 0, y, ¼, 0, -y, ~, etc., with y= 0.037. By superposltion of the Patterson sections from these two positions as origins, the positions of all atoms of the histidine residue (except hydrogen) were found (Fig. 2). From the smaller peaks three reasonable water-molecule oxygen positions were found, one being on a two-fold axis. The only other features in the superposition map were diffraction peaks around the zinc atom, and one small peak too near to other atomic positions to be a water molecule. Structure factors were calculated and gave R=ZIIFoI-IFd[/XIFo]=21%, for all observed re->0 .-,

Investigation of the reactions of hexanitrocobaltate(III) with amino acids. XIII. The structure and absolute configuration of (–)589-ab-(histidinato-N,N')-cdf-(histidinato-O,N,N')-e-nitrocobalt(III) monohydrate

“…In the crystal structure of [Cd(L-his) 2] (Fuess & Bartunik, 1976), the Co-O bond length is 0.2,4, longer than the Co-N bond lengths. Metal-oxygen distances are even longer in complexes [Zn(D-his)(L-his)]- (Harding & Cole, 1963), [Zn(D-his) 2] (Kretsinger, Cotton & Bryan, 1963) and [Cu(L-his)(L-asn)] (Ono, Shimanouchi, Sasada, Sakurai, Yamauchi & Nakahara, 1979); the principal coordination sites of histidine in these compounds are imidazole and amino N atoms, with a close approach of carboxylato O atoms. In the structures of (-)-[CoNO2(L-hiS)E].H20 and [Cu(Lhis)(D-his)(H202)].…”

Four-, Five- and Six-Coordinated ZnII Complexes of OH-Containing Ligands: Syntheses, Structure and Reactivity

“…[25] (distorted octahedral), Zn II ···O carboxylato distances of 2.91 Å and 2.79 Å observed in the case of two Zn II -histidino complexes, [26,27] (distorted octahedral), Zn II ···O perchlorato distances of 2.528 and 2.818 Å observed with the two crystallographically independent molecules present in the lattice of a Zn II -triazacyclododecane complex [28] (distorted trigonal bipyramidal), Zn II ···O crownether distances of 2.34, 2.56 and 2.60 Å observed in the case of the Zn-crown ether complex [29] (highly distorted trigonal bipyramidal). Each molecule in the lattice of 1 interacts with three other neighbor molecules via two hydrogen bonds, resulting in a total of six hydrogen bonds.…”

Structure, Disorder, and Molecular Dynamics in Zn(d,l-histidine)2: EPR of Copper Ion Dopants, X-ray Diffraction, and Calorimetric Studies

“…They observed an anomalous temperature dependence of the g-factor and the hyperfine coupling parameter at temperatures around 250 K, and attributed this behavior to a Jahn-Teller effect on the copper ions. The crystal structure of Zn(D,L-histidine) 2 at room temperature was reported by Harding and Cole, 14 who determined the positions of all atoms. They found two alternative positions for some of the water hydrogen atoms, and an underlying proton dynamics may be expected from these results.…”

“…13 An important ligand to metal ions is the amino acid histidine, and many investigations dealing with complexes of histidine with metal ions have been reported. The crystal structures of zinc, 14,15 cobalt, 16 cadmium, 17 nickel, 18 and copper 19 complexes show the bis(histidine) as a bidentate ligand, with the metal ion bound to imidazole and amino nitrogens, and to carboxylate oxygens, in tetrahedral, square planar, or octahedral coordinations.…”

“…14 Figure 1 displays an ORTEP projection of the molecule 34 at 293 K, showing the labeling of the atoms. Full accounts of the structural information including data collection procedure and structure refinement results are provided as Supporting Information (Tables S1-S6).…”