Thus the rings II to VII form a compact three-dimensional structure with the plane benzene ring I projecting outwards.References BEEVERS, C. A. & ROBERTSO~, J. H. (1950 There are four molecules of strychnine in the unit cell. As the heavy atom lies on the symmetry centre of the [010] projection, the application of the Fourier method for this projection follows the well-known lines developed for the phthalocyanine structure. For the non-centro-symmetrical [001] projection the phase angles, except for their signs, were derived from the intensity comparison of the isomorphous structures of the sulphate and the selenate. A symmetrical Fourier synthesis was made, and from this and the [010] projection the atomic positions were found. The strychnine structure thus derived proved to be concordant with that one of the competing structure formulas which just then was unequivocally accepted by the organic chemists. After suitable refinement, averaged errors amount to 0.08 A. for both projections.
A blue-green complex, glycylglycylglycinocopper(II) chloride sesquihydrate, has been crystallized from an aqueous solution containing equimolar proportions of glycylglycylglycine and cupric chloride. The boat-shaped crystals are monoclinic, space-group C2/c, with 8 formula units in a cell with dimensions a=21.36, b=6.72, c=15.64/~; fl=98 ° 15'.The metal atom is bonded to the terminal nitrogen and to the oxygen atom of the first peptide residue. In the crystal, the terminal carboxyl group is coordinated to a second copper atom, so that the structure consists of infinite -Cu-peptide-Cu-peptide-chains. These are cross-linked by a hydrogen-bond network making efficient use of the water molecules and chloride ions. The copper atoms are 5-coordinated. The configuration of the ligand atoms is tetragonal pyramidal: the 'top' of the pyramid is occupied by a water molecule and the corners of the base by the terminal nitrogen and peptide oxygen of one peptide chain, a carboxylic oxygen of another peptide, and a chloride ion.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.