Geometrical variations of two manganese(II) complexes with closely related quinoline-based tripodal ligands.

Structural analyses of the compounds di-μ-acetato-κ :'-bis-{[2-meth-oxy-,-bis-(quinolin-2-ylmeth-yl)ethanamine-κ ,','',]manganese(II)} bis-(tetra-phen-yl-borate) di-chloro-methane 1.45-solvate, [Mn(CO)(CHNO)](CHB)·1.45CHCl or [Mn(DQMEA)(μ-OAc)Mn(DQMEA)](BPh)·1.

Crystal structure of a mononuclear copper(II) complex with 2-methoxy-,-bis-(quinolin-2-yl-meth-yl)-ethyl-amine (DQMEA).

Structural characterization of the compound [Cu(CHN)(CHNO)](ClO)] or [Cu(CHN)(DQMEA)](ClO)] [DQMEA = 2-methoxy-,-bis-(quinolin-2-ylmeth-yl)ethyl-amine] {systematic name: (aceto-nitrile)[2-methoxy-,-bis(quinolin-2-ylmeth-yl)ethyl-amine]-copper(II) diperchlorate} by single-crystal X-ray diffraction reveals a complex cation with a tetra-dentate coordination of the DQMEA ligand along with monodentate coordination of a CHCN ligand to a single Cu center, with two perchlorate anions providing charge balance. The Cu center has a distorted square-pyramidal geometry in which the nitro-gen atoms of the DQMEA and CHCN ligands occupy the equatorial positions, while the oxygen atom of the DQMEA ligand resides in the axial position with an elongated Cu-O bond. The quinoline ring systems are nearly co-planar in the structure, while the linear CHCN ligand is tilted significantly below this plane, and the central nitro-gen of DQMEA is above it.

Crystal structure of a seven-coordinate manganese(II) complex with tris-(pyridin-2-ylmeth-yl)amine (TMPA).

Structural analysis of (acetato-κ,')(methanol-κ)[tris-(pyridin-2-ylmeth-yl)amine-κ,','',''']manganese(II) tetraphenyl-borate, [Mn(CHO)(CHN)(CHOH)](CHB) or [Mn(TMPA)(Ac)(CHOH)]BPh [TMPA = tris-(pyridin-2-ylmeth-yl)amine, Ac = acetate, BPh = tetra-phenyl-borate] by single-crystal X-ray diffraction reveals a complex cation with tetra-dentate coordination of the tripodal TMPA ligand, bidentate coordination of the Ac ligand and monodentate coordination of the methanol ligand to a single Mn center, balanced in charge by the presence of a tetra-phenyl-borate anion. The Mn complex has a distorted penta-gonal-bipyramidal geometry, in which the central amine nitro-gen and two pyridyl N atoms of the TMPA ligand, and two oxygen atoms of the acetate ligand occupy positions in the penta-gonal plane, while the third pyridyl nitro-gen of TMPA and the oxygen from the methanol ligand occupy the axial positions. Within the complex, the acetate O atoms participate in weak C-H⋯O hydrogen-bonding inter-actions with neighboring pyridyl moieties.

Immobilization of the aminopeptidase from Aeromonas proteolytica on Mg2+/Al3+ layered double hydroxide particles.

A novel biomaterial formed by the immobilization of the Aminopeptidase from Aeromonas proteolytica (AAP) on synthetic Mg2+ and Al3+ ion-containing layered double hydroxide (LDH) particles was prepared. Immobilization of AAP on the LDH particles in a buffered, aqueous mixture is rapid such that the maximum loading capacity, 1×10(-9) moles of AAP/mg LDH, is achieved in a few minutes. X-ray powder diffraction of LDH samples before and after treatment with AAP indicates that the enzyme does not intercalate between the layers of LDH, but instead binds to the surface.