N-(2-Nitro­oxyeth­yl)picolinamide

In the title mol­ecule, C8H9N3O4, the amide group is involved in the formation of an intra­molecular N—H⋯N hydrogen bond. In the crystal, mol­ecules related by translation along the a axis are linked into chains via weak inter­molecular C—H⋯O inter­actions

Bis(tetra­phenyl­phospho­nium) bis­[N-(trifluoro­methyl­sulfon­yl)dithio­carbimato(2−)-κ2 S,S′]zincate(II)

The title salt, (C24H20P)2[Zn(C2F3NO2S3)2], consists of a complex dianion and two tetra­phenyl­phospho­nium cations. The ZnII ion displays a distorted tetra­hedral coordination environment with four S atoms from two S,S′-chelated N-(trifluoro­methyl­sulfonyl­)dithio­carbimate anions. In the crystal, besides the ionic inter­action of the oppositely charged ions, inter­molecular C—H⋯O inter­actions between cations and anions are observed. One of the cations inter­acts with an inversion-related equivalent by π–π stacking between phenyl rings, with a centroid–centroid distance of 3.932 (4) Å

Centrosymmetric resonance-assisted intermolecular hydrogen bonding chains in the enol form of ␤-diketone: Crystal structure and theoretical study

Isobenzofuran-1(3H)-ones (phtalides) are heterocycles that present a benzene ring fused to a γ-lactone functionality. This structural motif is found in several natural and synthetic compounds that present relevant biological activities. In the present investigation, the 3-(2-hydroxy-4,4-dimethyl-6-oxocyclohexen-1-yl)isobenzofuran-1(3H)-one was characterized by single-crystal X-ray analysis. In the crystal structure, there are two molecules per asymmetric unit. One of them exhibits resonance assisted hydrogen bonds (RAHBs). Semi-empirical and DFT calculations were performed to obtain electronic structure and π-delocalization parameters, in order to better understand the energy stabilization of RAHBs in the crystal packing of the studied molecule. The structural parameters showed good agreement between theoretical and experimental data. The theoretical investigation revealed that the RAHBs stabilization energy is directly related to the electronic delocalization of the enol form fragment. In addition, RAHBs significantly affected the HOMO and charge distribution around the conjugated system

Crystal structure of two new polymeric copper(II) complexes active against Trypanosoma cruzi

We report here the characterization of two new polymeric copper(II) complexes containing 2-chlorobenzhydrazide (2-CH) and two N,N-donor ligands, namely, 1,10-phenanthroline (phen) and 4-4′-dimethoxy-2-2′-bipyridine (dmb). The structure of a new polymeric copper(II) complex in which a perchlorate anion acts as a bridge ligand is discussed in detail. In both complexes, spectral data reveals a bidentate coordination mode for hydrazide, perchlorate and N,N-donor ligand. These metal complexes and their free ligands were evaluated for their trypanocidal and cytotoxic activities and the complex with 1,10-phenanthroline has been much more active than benznidazole, a drug used in the treatment of Chagas disease. Keywords: Copper(II) complexes, Crystal structure, Trypanosoma cruzi, Cytotoxic activit