Coordination of a triazine ligand with CuII and AgI investigated by spectral, structural, theoretical and docking studies

Density functional theory (DFT) studies in HDAC-based chemotherapeutics: Current findings, case studies and future perspectives

Density Functional Theory (DFT) is a quantum chemical computational method used to predict and analyze the electronic properties of atoms, molecules, and solids based on the density of electrons rather than wavefunctions. It provides insights into the structure, bonding, and behavior of different molecules, including those involved in the development of chemotherapeutic agents, such as histone deacetylase inhibitors (HDACis). HDACs are a wide group of metalloenzymes that facilitate the removal of acetyl groups from acetyl-lysine residues situated in the N-terminal tail of histones. Abnormal HDAC recruitment has been linked to several human diseases, especially cancer. Therefore, it has been recognized as a prospective target for accelerating the development of anticancer therapies. Researchers have studied HDACs and its inhibitors extensively using a combination of experimental methods and diverse in-silico approaches such as machine learning and quantitative structure-activity relationship (QSAR) methods, molecular docking, molecular dynamics, pharmacophore mapping, and more. In this context, DFT studies can make significant contribution by shedding light on the molecular properties, interactions, reaction pathways, transition states, reactivity and mechanisms involved in the development of HDACis. This review attempted to elucidate the scope in which DFT methodologies may be used to enhance our comprehension of the molecular aspects of HDAC inhibitors, aiding in the rational design and optimization of these compounds for therapeutic applications in cancer and other ailments. The insights gained can guide experimental efforts toward developing more potent and selective HDAC inhibitors.

The Coordination Behavior of Two New Complexes, [(C7H10NO2)CdCl3]n(I) and [(C7H9NO2)CuCl2] (II), Based on 2,6-Dimethanolpyridine; Elaboration of the Structure and Hirshfeld Surface, Optical, Spectroscopic and Thermal Analysis

Two novel complexes, [(C₇H₁₀NO₂)CdCl₃]_n(I) and [(C₇H₉NO₂)CuCl₂],havebeen synthesized and characterized. Single crystal X-ray diffraction revealed that in compound (I), 2,6-dimethanol pyridinium acts as a monodentate ligand through the O atom of the hydroxyl group. Contrarily, the 2,6-dimethanol pyridine ligand interacts tridentately with the Cu(II) ion via the nitrogen atoms and the two oxygen (O, O’) atoms of the two hydroxyl groups. The structure’s intermolecular interactions were studied using contact enrichment ratios and Hirshfeld surfaces. Following metal coordination, numerous hydrogen connections between entities and parallel displacement stacking interactions between pyridine rings dictate the crystal packing of both compounds. The aromatic cycles generate layers in the crystal for both substances. Powder XRD measurements confirmed the crystalline sample phase purity. SEM confirmed the surface homogeneity, whereas EDX semi-quantitative analysis corroborated the composition. IR spectroscopy identified vibrational absorption bands, while optical UV-visible absorption spectroscopy investigated optical properties. The thermal stability of the two materials was tested using TG-DTA.

A binuclear Cd(II) complex containing bridging pyrimidine-based ligands

In this work, a pyrimidine-based ligand, N′-(amino(pyrimidin-2-yl)methylene)pyrimidine-2-carbohydrazonamide hydrate (APPH · H2O), and its binuclear complex of cadmium, [Cd(μ-APPH)Br]2, 1, were prepared and identified by elemental analysis, FT-IR, 1H NMR spectroscopy as well as single-crystal X-ray diffraction. X-ray structure analysis of 1 revealed octahedrally coordinated cadmium centers with a CdN4Br2 environment containing two bridging APPH ligands; each APPH ligand acts as an N4-donor (N2-donor toward each cadmium atom) and forms two five-membered chelate rings that are approximately perpendicular to each other. In the network of 1, the N–H · · · Br hydrogen bonds form motifs such as R 2 2 ( 12 ,   14 ) ,  R 6 6 ( 24 ,   26 ,   … ,   46 ) . ${\rm{R}}_{\rm{2}}^{\rm{2}}(12,{\rm{ }}14),{\rm{ R}}_{\rm{6}}^{\rm{6}}(24,{\rm{ }}26,{\rm{ }} \ldots ,{\rm{ }}46).$ The crystal network is further stabilized by π-π stacking interactions between pyrimidine rings. The optimized structures of the ligand and complex were investigated along with their charge distribution patterns by density functional theory and natural bond orbital analysis, respectively.