The reaction of 4,4'-bipyridylethane (bpe) and 4,4'-dipyridyl disulfide (dpds) with Zn(OAc)2.2H2O has led to the formation of two coordination polymers, [Zn(OAc)2(mu-bpe)].2H2O (1) and [Zn(OAc)2(mu-dpds)] (2). Both the compounds have zigzag coordination polymeric structures as revealed by X-ray crystallography. However, the presence of two lattice water molecules in 1 results in an interesting difference between the crystal structures. In 1, the carboxylate carbonyl oxygen atoms of the Zn(OAc)2 groups from two different adjacent zigzag polymers and four lattice water molecules form 24-membered hydrogen-bonded rings (graph set notation, R6 (6)(24)). One of the two bpe ligands associated with each Zn(II) center passes through the center of this ring to form a two-dimensional hydrogen-bonded coordination polymeric structure. In the solid state, the adjacent 24-membered hydrogen-bonded rings further fuse together through O-H...O hydrogen bonds among four waters to form cyclic (H2O)4. This results in a one-dimensional hydrogen-bonded ribbon-like polymer comprising fused alternating 24- and eight-membered O-H...O hydrogen-bonded rings. One of the bpe ligands passes through the center of the larger ring to produce an unexpected single self-penetrating three-dimensional hydrogen-bonded network with polyrotaxane-like association. A neutron diffraction study provides a detailed description of the hydrogen bonds involved.
Phosphatidylinositol 3-kinases (PI3K) are lipid kinases involved in critical cellular processes, and their role in cancer and inflammatory disorders makes them key targets for drug development.
The study involves analyzing the crystal structure of human PI3Kγ, simulating interactions with stilbenoid compounds like piceatannol and resveratrol, and designing modified derivatives to enhance their effectiveness.
Findings indicate that these compounds bind to the ATP binding site of PI3Kγ, with structural modifications leading to stronger interactions that could result in the development of more potent inhibitors for this enzyme.
Competition and cooperation of charge-assisted anion-π interactions and hydrogen bonding were explored in the solid state and in solutions of 1-ethyl-4-carbomethoxypyridinium iodide, the compound utilized by Kosower to calculate solvent polarity Z-indices. X-ray structural analysis of this salt revealed multiple short contacts of iodide anions with hydrogen atoms and aromatic rings of pyridinium cations. Geometric characteristics, quantum theory of atoms in molecules (QTAIM), and noncovalent interaction (NCI) analysis of these contacts indicated comparable interaction energies of the anion-π and hydrogen bonding between iodide and pyridinium cation.
Instituto de Física de São Carlos, Universidade de São Paulo, USP, Avenida Trabalhador São-Carlense, No. 400 Parque Arnold Schmidt - CEP 13566-590, São Carlos, SP, Brazil.
The study examines N-(5-nitrothiazol-2-yl)furan-2-carboxamide (NTFC) as a potential inhibitor for rheumatoid arthritis, focusing on its synthesis and crystallization techniques.
NTFC has a unique structure featuring thiazole and furan rings connected by a planar C-N-C(=O)-C segment; crystal analysis revealed significant hydrogen bonding and effective molecular interactions.
Molecular docking studies indicated that NTFC may effectively inhibit the DHODH enzyme, showing promising coupling energies similar to leflunomide, a known rheumatoid arthritis treatment.
Cholesterol is a major component of biomembranes that impacts membrane order, permeability, and lateral organization, but the precise molecular mechanisms of cholesterol's actions are still under investigation. Density functional theory (DFT) calculations have opened the fingerprint vibration bands of large molecules to detailed spectral analysis. For cholesterol, Raman spectral interpretation for conformational structure and hydrogen bonding is now possible.
The title compound, bis-[di-thio-bis-(formamidinium)] hexa-bromido-ruthenium dibromide trihydrate, [(NH)CSSC(NH)][RuBr]Br·3HO, crystallizes in the ortho-rhom-bic system, space group , = 4. The [RuBr] anionic complex has an octa-hedral structure. The Ru-Br distances fall in the range 2.
