Crystal structure of aqua(glycyl)-L-tryptophanatocopper(II) dihydrate

Abstract

The crystal structure of the title compound has been determined by the heavy-atom method from a three-dimensional X-ray diffraction study. Least-squares refinement, based on 1 119 visually estimated independent reflections, has reduced R to 0.109. Crystals are orthorhombic, a= 7.74(4), b= 13.78(3), c= 14.81 (3)Å, space group P2₁2₁2₁ and Z= 4.

In the complex the peptide molecule behaves as a terdentate chelate via its terminal amino-group, peptide nitrogen atom, and the carboxylate ion. The single peptide nitrogen is deprotonated. The Cu^II atom has co-ordination number 4, the peptide atoms and one water molecule forming an approximate square.