Diaqua-bis-(5-carb-oxy-2-propyl-1H-imidazole-4-carboxyl-ato-κN,O)cadmium(II) 3.5-hydrate.

In the title complex, [Cd(C(8)H(9)N(2)O(4))(2)(H(2)O)(2)]·3.5H(2)O, the Cd(II) is coordinated by two water mol-ecules and N,O-chelated by two 5-carb-oxy-2-propyl-1H-imidazole-4-carboxyl-ate anions in a distorted octa-hedral geometry. The two imidazole rings are oriented to each other with a dihedral angle of 75.

Diaqua-bis-(5-carb-oxy-2-propyl-1H-imidazole-4-carboxyl-ato-κN,O)manganese(II) 3.5-hydrate.

In the title complex, [Mn(C(8)H(9)N(2)O(4))(2)(H(2)O)(2)]·3.5H(2)O, the Mn(II) cation is six-coordinated by two N,O-bidentate H(2)pimda(-) ligands (H(2)pimda(-) = 5-carb-oxy-2-propyl-1H-imidazole-4-carboxyl-ate) and two water mol-ecules in a distorted octa-hedral environment. The complete solid-state structure can be described as a three-dimensional supra-molecular framework stabilized by a wide range of O-H⋯O and N-H⋯O hydrogen bonds.

Diaqua-bis-(5-carb-oxy-2-propyl-1H-imidazole-4-carboxyl-ato-κN,O)zinc(II) 3.5-hydrate.

In the title complex, [Zn(C(8)H(9)N(2)O(4))(2)(H(2)O)(2)]·3.5H(2)O, the Zn(II) ion is coordinated by two N,O-bidentate H(2)pimda ligands (H(3)pimda = 2-propyl-1H-imidazole-4,5-dicarb-oxy-lic acid) and two water mol-ecules in a distorted octa-hedral environment. In the crystal structure, extensive inter-molecular O-H⋯O and N-H⋯O hydrogen bonds stabilize the three-dimensional supra-molecular network.

Diaqua-bis(5-carb-oxy-2-propyl-1H-imidazole-4-carboxyl-ato-κN,O)nickel(II) N,N-dimethyl-formamide disolvate.

In the title complex, [Ni(C(8)H(9)N(2)O(4))(2)(H(2)O)(2)]·2C(3)H(7)NO, the Ni(II) atom is six-coordinated by two N,O-bidentate 5-carb-oxy-2-propyl-1H-imidazole-4-carboxyl-ate ligands and two water mol-ecules in a distorted octa-hedral environment. The methyl C and H atoms of the two ligands are disordered over two sets of sites in 0.74 (2):0.

Diaqua-bis(5-carb-oxy-2-propyl-1H-imidazole-4-carboxyl-ato-κN,O)manganese(II) N,N-dimethyl-formamide disolvate.

In the title complex, [Mn(C(8)H(9)N(2)O(4))(2)(H(2)O)(2)]·2C(3)H(7)NO, the Mn(II) atom, lying on an inversion centre, is six-coordinated by two N,O-bidentate 5-carb-oxy-2-propyl-1H-imidazole-4-carb-oxyl-ate ligands and two water mol-ecules in a distorted octa-hedral environment. In the crystal structure, the complex mol-ecules and dimethyl-formamide solvent mol-ecules are linked by N-H⋯O and O-H⋯O hydrogen bonds into a two-dimensional supra-molecular network parallel to (001).

Poly[diaqua-bis(μ-4-carb-oxy-2-propyl-1H-imidazole-5-carboxyl-ato-κN,O:O)calcium(II)].

In the title complex, [Ca(C(8)H(9)N(2)O(4))(2)(H(2)O)(2)](n), the Ca(II) atom is eight-coordinated in a distorted square-anti-prismatic environment. The water-coordinated Ca atom is N,O-chelated by the monocarboxyl-ate anion; the carboxyl -CO(2) portion engaged in chelation bears an acid hydrogen. The free -CO(2) portion engages in bonding to adjacent Ca atoms.

μ-Aqua-κO:O-di-μ-4-methyl-benzoato-κO:O'-bis-[(4-methyl-benzoato-κO)(1,10-phenanthroline-κN,N')nickel(II)].

In the title dinuclear complex, [Ni(2)(C(8)H(7)O(2))(4)(C(12)H(8)N(2))(2)(H(2)O)], each Ni(II) atom is six-coordinated by three carboxylate O atoms from three 4-methyl-benzoate ligands, two N atoms from two 1,10-phenanthroline ligands, and one μ(2)-bridging aqua ligand. The dimeric complex is located on a crystallographic twofold axis and each Ni atom displays a distorted octa-hedral coordination geometry. The crystal structure is stabilized via intra-molecular hydrogen bonding of the bridging water mol-ecule and the uncoordinated carboxyl-ate O atoms, and by C-H⋯O and π-π stacking inter-actions [centroid-centroid distances between neighbouring phenanthroline ring systems and between the benzene ring of a 4-methyl-benzoate unit and a phenanthroline ring system are 3.

Poly[[diaqua-bis[μ-(2,4-dichloro-phen-oxy)acetato]calcium(II)] monohydrate].

In the title coordination polymer, {[Ca(C(8)H(5)Cl(2)O(3))(2)(H(2)O)(2)]·H(2)O}(n), the Ca(II) atom is eight-coordinated by six O atoms from four different (2,4-dichloro-phen-oxy)acetate ligands and two water mol-ecules, and displays a distorted square-anti-prismatic coordination geometry. The compound forms an infinite zigzag chain through connection of the metal centers by (2,4-dichlorphen-oxy)acetate ligands and hydrogen bonding of coordinated and inter-stitial water mol-ecules. These chains are further hydrogen bonded with neighboring chains, forming a supra-molecular network.

Poly[(μ-3,5-dinitro-2-oxidobenzoato)(μ-3-hydroxy-pyridine)copper(II)].

A new coordination polymer, [Cu(C(7)H(2)N(2)O(7))(C(5)H(5)NO)](n), exhibits a double-chain structure, in which 3,5-dinitro-2-oxidobenzoate and 3-hydroxy-pyridine both act as bridging ligands, -connecting adjacent copper(II) centers to form an infinite double-stranded chain. The asymmetric unit contains one Cu(II) ion, one 3,5-dinitro-2-oxidobenzoate ligand and a 3-hydroxy-pyridine ligand. Coordination by one N atom and three O atoms from two different 3,5-dinitro-2-oxidobenzoate ligands and a 3-hydroxy-pyridine ligand creates a square-planar Cu(II) center, which is augmented by a less tightly bonded fifth phenol O atom to form a square-pyramidal five-coordinate complex with an essentially planar base.

Poly[[(μ(4)-5-amino-isophthalato)aqua-iron(II)] dihydrate].

In the title three-dimensional coordination polymer, {[Fe(C(8)H(5)NO(4))(H(2)O)]·2H(2)O}(n), the Fe(II) atom exhibits a distorted octa-hedral geometry, being coordinated by one N and four O atoms from four 5-amino-isophthalate ligands and one water mol-ecule. In addition, the crystal structure is stabilized by numerous O-H⋯O and N-H⋯O hydrogen bonds.

Bis-(1H-benzimidazole-κN)bis(4-methyl-benzoato-κO,O')cobalt(II).

In the title mononuclear complex, [Co(C(8)H(7)O(2))(2)(C(7)H(6)N(2))(2)], the Co(II) atom is coordinated by four carboxylate O atoms from two 4-methyl-benzoate ligands and two N atoms from two benzimidazole ligands in an octa-hedral coordination geometry. The molecules are assembled via inter-molecular N-H⋯O hydrogen-bonding inter-actions into a three-dimensional network.

Tetra-aqua-bis(1-hydr-oxy-2-naphthoato-κO)zinc(II).

In the title mononuclear complex, [Zn(C(11)H(7)O(3))(2)(H(2)O)(4)], the Zn(II) atom is located on a centre of inversion and is coordinated by two O atoms from two 1-hydr-oxy-2-naphthoate ligands and four water mol-ecules in an octa-hedral geometry. The structure is consolidated by inter-molecular O-H⋯O hydrogen bonding, as well as by a π-π stacking inter-action [centroid-centroid distance 3.762 (2)Å] between adjacent naphthyl ring systems.

High-level expression and purification of Escherichia coli oligopeptidase B.

Oligopeptidase B (OpdB) of Escherichia coli, previously called protease II, has a trypsin-like specificity, cleaving peptides at lysine and arginine residues and belongs to the prolyl oligopeptidase family of new serine peptidases. In this study, we report the fusion expression of E. coli oligopeptidase B with an N-terminal histidine tag using pET28a as the expression vector.