New Azo Derivative of ß-Diketones and Its Cu(II), Co(II) Complexes: Synthesis, Theoretical Study and Biological Activity.

The paper is focused on biological activity and theoretical study of the structure and properties of a new azo derivative of ß-diketones and its complexes with some metals. The aim of our work was to study the structure and properties of the newly synthesized compound as well as to theoretically determine the possibility of complex formation with the Cu(II) or Co(II) ions. A compound with the same substituents R1=R2=CH3 was chosen for the study. A synthesized azo compound based on 4-amino antipyrine and its complexes with Cu(II), Co(II) in solution and solid phase is reported. The structures of these compounds have been testified by X-ray, IR and  NMR spectroscopy. The combined experimental and theoretical approach was used. To study the structure and properties of the synthesized compound, as well as its possible complex formation with the Cu(II), quantum-chemical calculations were carried out the 6-31G basis set and the electron density functional theory (DFT) method. These 3-(1-phenyl-2,3-dimethyl-pyrazolone-5) azopentadione-2,4 (PDPA) with Cu(II) and Co(II) complexes had effective inhibition against butyrylcholinesterase and acetylcholinesterase. IC50 values were found as 19.03, 3.64 µM for AChE and 28.47, 8.01 µM for BChE, respectively. Cholinesterase inhibitors work to slow down the acetylcholine's deterioration.

Crystal structure of 1,1-di-acetyl-ferrocene dihydrazone.

The title compound, [Fe(C7H9N2)2], crystallizes with two crystallographically independent mol-ecules in the unit cell. These represent the chiral atropoisomers distinguished by the mutual arrangement of the two acet-yl-hydrazone groups with a cis conformation of the C=N bonds. The two cyclo-penta-dienyl (Cp) rings are planar and nearly parallel, the tilt between the two rings being 3.16 (16)° [4.40 (18)° for the second independent mol-ecule]. The conformation of the Cp rings is close to eclipsed, the twist angle being 0.1 (2)° [3.3 (2)°]. The two acet-yl-hydrazone substituents are also planar and are inclined at 13.99 (15)/9.17 (16)° [6.83 (17)/14.59 (15)°] relative to the Cp rings. The Fe-C bond lengths range from 2.035 (3) to 2.065 (2) Å, with an average of 2.050 (3) Š[2.036 (3) to 2.069 (2), average 2.046 (3) Å], which agrees well with those reported for most ferrocene derivatives. In the crystal, the mol-ecules form dimers via two strong N-H⋯N hydrogen bonds. The dimers are linked into a three-dimensional framework by weak N-H⋯N hydrogen bonds.

[N-(1-Aza-nidyl-2,2,2-trichloro-ethyl-idene)-2,2,2-trichloro-ethanimidamide]-copper(II).

The title compound, [Cu(C(4)H(2)Cl(6)N(3))(2)], was obtained by the reaction of CCl(3)CN with ammonia in presence of CuCl. The Cu(II) atom is located about an inversion centre. The mol-ecule consists of three planar units (one central square CuN(4) and two C(2)N(3) fragments), adopting a staircase-like structure. The six-membered metallocycles have a sofa conformation with the Cu atom out of the plane of the 1,3,5-triaza-penta-dienyl ligands by 0.246 (5) Å. The ipso-C atoms of the CCl(3) substituents are slightly out of the 1,3,5-triaza-penta-dienyl planes by 0.149 (6) and -0.106 (6) Å. The CCl(3) groups of each 1,3,5-triaza-penta-dienyl ligand are practically in the energetic-ally favourable mutually eclipsed conformation. In the crystal, the mol-ecules are packed in stacks along the a axis. The mol-ecules in the stacks are held together by two additional axial Cu⋯Cl inter-actions of 3.354 (2) Å. Taking the axial Cu⋯Cl inter-actions into account, the Cu(II) atom exhibits a distorted [4 + 2]-octa-hedral coordination environment. The stacks are bound to each other by weak inter-molecular attractive Cl⋯Cl [3.505 (2)-3.592 (3) Å] inter-actions.