Aqua(4-methylquinoline-κN)[N-(2-oxidobenzylidene)glycinato-κ3 O,N,O′]copper(II) hemihydrate

The title complex, [Cu(C9H7NO3)(C10H9N)(H2O)]·0.5H2O, crystallizes with two independent formula units in the asymmetric unit; the solvent molecule is located on a twofold axis of symmetry. The CuII atom is coordinated by one tridentate N-salicylideneglycinate Schiff base ligand, one 4-methylquinoline ligand and one water molecule, leading to a slightly distorted square-pyramidal N2O3 geometry. In the crystal structure, the molecules are linked by O—H⋯O hydrogen bonds into linear chains in the [100] direction. The structure is further stabilized by intermolecular C—H⋯O interactions and C⋯C contacts with C⋯C = 3.3058 (2), 3.3636 (2) and 3.3946 (2) Å.

The title complex, [Cu(C 9 H 7 NO 3 )(C 10 H 9 N)(H 2 O)]Á0.5H 2 O, crystallizes with two independent formula units in the asymmetric unit; the solvent molecule is located on a twofold axis of symmetry. The Cu II atom is coordinated by one tridentate N-salicylideneglycinate Schiff base ligand, one 4methylquinoline ligand and one water molecule, leading to a slightly distorted square-pyramidal N 2 O 3 geometry. In the crystal structure, the molecules are linked by O-HÁ Á ÁO hydrogen bonds into linear chains in the [100] direction. The structure is further stabilized by intermolecular C-HÁ Á ÁO interactions and CÁ Á ÁC contacts with CÁ Á ÁC = 3.3058 (2), 3.3636 (2) and 3.3946 (2) Å .

S1. Comment
Schiff bases, as condensation products of carbonyls and amines, and their coordination compounds find their utilization in different branches of chemical technology (Katsuki, 2003) and participate in some biochemical pathways, e.g. transamination processes, catalyzed by metalloenzymes.
In connection with our recent studies on copper and zinc salicylidene-derived Schiff base complexes, we report now the structure of (I). The Schiff base (Salgly) ligand represents a condensation product of salicylaldehyde and glycine. The title complex, in the form of an anhydrous compound, showed significant microbistatic and fungistatic effects (Valent et al., 2002). Moreover, similar compounds derived from different N-salicylideneamino acids have been intensively studied and showed some remarkable biological features, from which the antioxidant (Vančo et al., 2008), antiflogistic, antirheumatic (Bauerová et al., 2005, or antidiabetic activities (Vančo et al., 2004) could be considered as the most interesting.
To date, only four X-ray structures of monomeric copper(II) complexes involving the aqua-(N-salicylideneglycinato-

S2. Experimental
The title complex, (I), was prepared by the reaction of an ethanol/water solution (2:1, v/v) of aqua-(Nsalicylideneglycinato)copper(II) hemihydrate (Kishita et al., 1964) with an ethanolic solution of 4-methylquinoline in the molar ratio of 1:4. The reaction mixture was stirred at 60 °C for 30 minutes. After cooling overnight, well developed single crystals of (I) suitable for X-ray analysis were isolated.

S3. Refinement
C-bound H-atoms were included in the riding model approximation with C-H distances of 0.95 Å (C aromatic ), 0.98 Å (CH 3 ) and 0.99 Å (CH 2 ), and with U iso (H) values of 1.2U eq (CH 2 , C aromatic ) or 1.5U eq (C methyl ). The O-bound H atoms were refined, with the O-H distances restrained to 0.90 (2) Å and with U iso (H) values of 1.5U eq (O water ); distances are given in Table 1.

Crystal data
[Cu(C 9 H 7 NO 3 )(C 10 H 9 N)(H 2 O)]·0.5H 2 O M r = 410.9 Monoclinic, P2/c Hall symbol: -P 2yc a = 10.0966 (7) Special details Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes. Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > σ(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.