A novel mixed ligand Cu(II) complex of 4,4,4-trifluoro-1-phenyl-1,3-butanedione and 8-hydroxyquinoline was synthesized and spectroscopically characterized. The phenolate oxygen bridged dinuclear (polymorph 1) and solvent-induced mononuclear (polymorph 2) forms were obtained using DMSO and acetic acid solvents. The solvato supramolecular isomeric forms (P and P2₁/a) of the complex are confirmed by the single crystal X-ray diffraction method. In polymorph 1, a hydrogen-bonded one-dimensional network is constructed by C–H⋯O contacts, whereas, in polymorph 2, a two-dimensional ladder-like architecture is formed by the interplay of C–H⋯O, C–H⋯F and F⋯F contacts. The vital role of distinct non-covalent interactions in the establishment of a unique structural topology is analysed by Hirshfeld surfaces, 2D fingerprint plots, QTAIM and the NCI index model. The anisotropies in the three-dimensional structural topology are visualized through their energy frameworks and evidenced by their interaction energies. The electronic structures of the polymorphs were optimized by density functional theory calculations to explore their coordination stability and chemically reactive parameters. Polymorph 1 exhibits potential antibacterial activity against methicillin-resistant Staphylococcus aureus with a minimum inhibitory concentration of 8 μg mL⁻¹. Further, polymorphs were docked to penicillin-binding protein 2, where polymorph 1 had a binding score of −10.0 kcal mol⁻¹, greatly supporting the in vitro results.

Methane is a greenhouse gas which poses a great threat to life on earth as its emissions directly contribute to global warming and methane has a 28-fold higher warming potential over that of carbon dioxide. Ruminants have been identified as a major source of methane emission as a result of methanogenesis by their respective gut microbiomes. Various plants produce highly bioactive compounds which can be investigated to find a potential inhibitor of methyl-coenzyme M reductase (the target protein for methanogenesis). To speed up the process and to limit the use of laboratory resources, the present study uses an in-silico molecular docking approach to explore the anti-methanogenic properties of phytochemicals from Cymbopogon citratus, Origanum vulgare, Lavandula officinalis, Cinnamomum zeylanicum, Piper betle, Cuminum cyminum, Ocimum gratissimum, Salvia sclarea, Allium sativum, Rosmarinus officinalis and Thymus vulgaris. A total of 168 compounds from 11 plants were virtually screened. Finally, 25 scrutinized compounds were evaluated against methyl-coenzyme M reductase (MCR) protein using the AutoDock 4.0 program. In conclusion, the study identified 21 out of 25 compounds against inhibition of the MCR protein. Particularly, five compounds: rosmarinic acid (−10.71 kcal/mol), biotin (−9.38 kcal/mol), α-cadinol (−8.16 kcal/mol), (3R,3aS,6R,6aR)-3-(2H-1,3-benzodioxol-4-yl)-6-(2H-1,3-benzodioxol-5-yl)-hexahydrofuro[3,4-c]furan-1-one (−12.21 kcal/mol), and 2,4,7,9-tetramethyl-5decyn4,7diol (−9.02 kcal/mol) showed higher binding energy towards the MCR protein. In turn, these compounds have potential utility as rumen methanogenic inhibitors in the proposed methane inhibitor program. Ultimately, molecular dynamics simulations of rosmarinic acid and (3R,3aS,6R,6aR)-3-(2H-1,3-benzodioxol-4-yl)-6-(2H-1,3-benzodioxol-5-yl)-hexahydrofuro[3,4-c]furan-1-one yielded the best possible interaction and stability with the active site of 5A8K protein for 20 ns.

Natural products are important leads in drug discovery. The search for effective plant-derived agents or their synthetic analogues has continued to be of interest to biologists and chemists for a long time. Herein, we have synthesized a novel compound, P1C, and P1C-Tit*CAgNPs from chitosan; P1C is a precursor and an anti-inflammatory candidate, which has been validated by molecular docking studies. The synthesized P1C-Tit*CAgNPs showed monodisperse, spherical, and cationic nature and antioxidant properties, protecting destabilization of the erythrocyte membrane by the azo compound 2,2′-azobis(2-amidinopropane)dihydrochloride (AAPH); the involvement of NPs as a protective agent for biomolecules, such as DNA and protein, followed by the treatment of NPs with AAPH was confirmed. The inhibition of cellular damage and leakage of cellular inflammatory agents was confirmed by AFM, SEM, TEM, SDS-PAGE, LDH, and PLA2 enzyme inhibition via in vitro studies. The anti-inflammatory property of P1C was further validated by in silico molecular docking studies and showed that, the P1C best pose aligned to PLA2 compared to standard drug. The significant anticancer property of P1C-Tit*CAgNPs was confirmed against MCF7, U373, and C6 cancer cell lines. Thus, the present study highlights the synthesized P1C in P1C-Tit*CAgNPs as a target PLA2-specific anti-inflammatory candidate, and further tuning of small and development-functionalized nanoparticles has a great future in medicine; hence, their clinical applications are warranted.

The post-synthetic approach is a powerful strategy to modify organic linkers and/or metal node functionality without disrupting the parent metal and ligand coordination. Engineering new crystal forms of the same molecule and investigating the relationship among them is a challenging area of crystallography to explore the structure–property relationship. In this regard, a new crystal form of homoleptic 4,4,4-trifluoro-1-(2-naphthyl)-1,3-butanedione (TFNB) Cu(II) complex [Cu(TFNB)₂(C₂H₆SO)] (1) is characterized by the single crystal X-ray diffraction method which revealed that complex 1 is an isostructural solvate of previously reported [Cu(TFNB)₂(C₂H₆SO)₂] (2). In complex 1, a single DMSO solvent molecule is apically coordinated to the Cu(II) ion to form a distorted square pyramidal geometry with two chelating rings of TFNB, while in complex 2, the solvent molecules are present in pairs related by the inversion center leading to a six coordinated octahedral geometry. Besides, the newly synthesized heteroleptic Cu(II) complex of TFNB with 8-hydroxyquinoline exists in two pseudopolymorphic forms, [Cu(TFNB)(8HQ)]₂ (3) and [Cu(TFNB)(8HQ)]·CH₃COOH (4) via non-bridging solvent incorporation. Complex 3 is a phenoxide bridged binuclear complex that adopts a distorted square pyramidal geometry. In complex 4, the bridging action of phenoxide is broken by the effect of a guest solvent (acetic acid) molecule, leading to the formation of a discrete mononuclear complex with a square planar geometry. The solvent induced structural transformations on the metal coordination sphere and molecular interaction topology of Cu(II) complexes, via single crystal coordinated solvent exchange (complexes 1 and 2) and solvent molecule participation in the crystal lattice (complexes 3 and 4), were comparatively analyzed and investigated by combined crystallographic and quantum computational studies.