[1,2-Bis­(diisopropyl­phosphan­yl)ethane-κ2 P,P′]dichloridonickel(II)–9H-carbazole (1/2)

In the title compound, [NiCl2(C14H32P2)]·2C12H9N, the neutral [Ni(dppe)Cl2] complex [dppe is 1,2-bis­(diisopropyl­phosphan­yl)ethane] consists of a tetracoordinated Ni2+ cation and has a crystallographic twofold axis passing through the metal atom and the mid-point of the CH2—CH2 bond of the dppe ligand. The metal atom shows slight tetra­hedral distortion from an ideal square-planar coordination geometry, as reflected in the dihedral angle between NiCl2 and NiP2 planes of 15.32 (2)°. The 9H-carbazole ring system is essentially planar (r.m.s. deviation = 0.022 Å). In the crystal packing, there are two symmetry-related 9H-carbazole mol­ecules between two adjacent NiII complexes, with an angle between the carbazole mean planes of ca 77°

[1,2-Bis­(diisopropyl­phosphan­yl)ethane-κ2 P,P′]dichloridonickel(II)

In the crystal structure of title compound, [NiCl2(C14H32P2)], the NiII atom lies on a twofold rotation axis and shows a slightly distorted square-planar coordination geometry, with a dihedral angle of 10.01 (8)° between the cis-Cl—Ni—Cl and cis-P—Ni—P planes. There is no significant inter­molecular inter­action except very weak C—H⋯Cl inter­actions. The crystal studied was a racemic twin

Perturbation of the Dimer Interface of Triosephosphate Isomerase and its Effect on Trypanosoma cruzi

Most of the enzymes of parasites have their counterpart in the host. Throughout evolution, the three-dimensional architecture of enzymes and their catalytic sites are highly conserved. Thus, identifying molecules that act exclusively on the active sites of the enzymes from parasites is a difficult task. However, it is documented that the majority of enzymes consist of various subunits, and that conservation in the interface of the subunits is lower than in the catalytic site. Indeed, we found that there are significant differences in the interface between the two subunits of triosephosphate isomerase from Homo sapiens and Trypanosoma cruzi (TcTIM), which causes Chagas disease in the American continent. In the search for agents that specifically inhibit TcTIM, we found that 2,2′-dithioaniline (DTDA) is far more effective in inactivating TcTIM than the human enzyme, and that its detrimental effect is due to perturbation of the dimer interface. Remarkably, DTDA prevented the growth of Escherichia coli cells that had TcTIM instead of their own TIM and killed T. cruzi epimastigotes in culture. Thus, this study highlights a new approach base of targeting molecular interfaces of dimers

Crystal structure of 1-mesityl-3-methyl-4-phenyl-1H-1,2,3-triazol-3-ium iodide

In the cation of the title salt, C18H20N3+·I−, the mesityl and phenyl rings are inclined to the central triazolium ring by 61.39 (16) and 30.99 (16)°, respectively, and to one another by 37.75 (15)°. In the crystal, molecules are linked via C—H...I hydrogen bonds, forming slabs parallel to the ab plane. Within the slabs there are weak π–π interactions present involving the mesityl and phenyl rings [inter-centroid distances are 3.8663 (18) and 3.8141 (18) Å]

Mononuclear and Tetranuclear Copper(II) Complexes Bearing Amino Acid Schiff Base Ligands: Structural Characterization and Catalytic Applications

Two new glycine-Schiff base copper(II) complexes were synthesized. Single crystal X-ray diffraction (SCXRD) allowed us to establish the structure of both complexes in the solid state. The glycine-Schiff base copper(II) complex derived from 2′-hydroxy-5′-nitroacetophenone showed a mononuclear hydrated structure, in which the Schiff base acted as a tridentate ligand, and the glycine-Schiff base copper(II) complex derived from 2′-hydroxy-5′-methylacetophenone showed a less common tetranuclear anhydrous metallocyclic structure, in which the Schiff base acted as a tetradentate ligand. In both compounds, copper(II) had a tetracoordinated square planar geometry. The results of vibrational, electronic, and paramagnetic spectroscopies, as well as thermal analysis, were consistent with the crystal structures. Both complexes were evaluated as catalysts in the olefin cyclopropanation by carbene transference, and both led to very high diastereoselectivity (greater than 98%)