Detail of "64911-17-7"

Reference

A crystallographic study of the structure of glycyl-L-alaninatocopper(II) hydrate and the conformations of copper(II)

A crystallographic study of the structure of glycyl-L-alaninatocopper(II) hydrate and the conformations of copper(II).cntdot.dipeptide complexes. Freeman, Hans C.; Healy, Michael J.; Scudder, Marcia L. (Sch. Chem., Univ. Sydney, Sydney, Aust.). 64911-17-7 which is the cas registry number is also used here. J. Biol. Chem., 252(24), 8840-7 (English) 1977. CODEN: JBCHA3. DOCUMENT TYPE: Journal CA Section: 75 (Crystallization and Crystal Structure) The crystals of glycyl-L-alaninatocopper(II) monohydrate are orthorhombic, space group P212121, with a 9.18(1), b 9.75(1), and c 8.94(1) A, d.(exptl.) = 1.86(2) and d.(calcd.) = 1.87 for Z = 4. The structure was solved with x-ray diffraction data and refined to an R of 0.045. The Cu atom is bonded to the dipeptide at the N(amino) atom, the N(peptide) atom of the deprotonated peptide group, and an O(carboxyl) atom. These three donor atoms occupy equatorial coordination positions. The fourth equatorial coordination position is filled by the free O(carboxyl) atom of an adjacent complex. A fifth bond in an axial direction joins the Cu atom to the O(peptide) atom of a 2nd adjacent complex. The coordination no. of the Cu atom is five, and the coordination geometry is square-pyramidal. There is a short nonbonded contact (3.0 .ANG.) between the C.beta. atom of the alanyl side chain and an O atom of the adjacent carboxyl group. Similar C.beta....O contacts exist in all relevant Cu-dipeptide complexes. These contacts restrict the amino-acid side chains to quasiaxial orientations. The chelate ring conformations vary over a wide range and are strongly influenced by intermol. contacts in the solid state. The structural results provide no support for the hypothesis that the restrictions on side-chain orientations are more severe in the COOH-terminal chelate. .