Single-crystal X-ray Diffraction Research Articles

Supramolecular assembly of mebendazolium and dihydrogen phosphate ions in a new anthelmintic salt

A new mebendazolium dihydrogen phosphate phosphoric acid solid material was obtained and characterized by single-crystal X-ray diffraction and complementary solid-state techniques {systematic name: 5-benzoyl-2-[(methoxycarbonyl)amino]-1H-1,3-benzodiazol-3-ium dihydrogen phosphate–phosphoric acid (1/1), C16H14N3O3 +·H2PO4 −·H3PO4}. Structure solution confirmed proton transfer from phosphoric acid towards the basic imidazole ring of mebendazole. The mebendazolium cation and the dihydrogen phosphate anion assemble in the solid state in a cyclic hydrogen-bond-driven supramolecular motif, as observed in all mebendazolium/oxyanions structures reported in the literature. This salt crystallizes in the monoclinic P21/c (No. 14) space group. A detailed study of the crystal structure performed by atom-to-atom and global Hirshfeld surface analysis indicates that several hydrogen bonds act as the main intermolecular interactions stabillizing the material. The new material is stable up to 458 K.

Discovery, Isolation, and Characterization of 23-Spirocholestane Derivatives as Novel Plant Root Growth Inhibitors from Ypsilandra thibetica.

In the present study, we first discovered that the 70% ethanol extract of Ypsilandra thibetica significantly inhibited Arabidopsis root growth. Through a bioactivity-guided strategy, 18 rare 23-spirocholestane derivatives (1-18), including 12 new ones (1-12), featuring a dioxane ring between C-24/C-23 of the aglycone moiety and C-1'/C-2' of the d-fucose ligand, were obtained from the strongest active elution fraction. Their structures were elucidated via a comprehensive method of MS and NMR spectroscopy, single-crystal X-ray diffraction, and chemical methods. Evaluation of their inhibitory effects of all isolates on Arabidopsis root growth revealed that 5/6, 3/4, 1, and 2 exhibited pronounced activity, with EC50 values of 6.89, 9.13, 18.01, and 26.83 μM, respectively. Then, a preliminary structure-activity relationship (SAR) analysis of these compounds was conducted. Furthermore, transcriptome data indicated that Arabidopsis responded to the stress caused by these bioactive compounds through the modulation of ethylene and auxin signaling pathways and the activation of various detoxification-related genes. Finally, the herbicidal evaluation showed that 3/4 and 5/6 significantly inhibited the root growth of Echinochloa crusgalli, while 3/4 remarkably suppressed the root growth of Lolium multiflorum. These findings highlight that 23-spirocholestane derivatives represent promising candidates for the development of new bioherbicides.

High Pressure Synthesis of Pr2O5 - A Unique Lanthanoid(IV) Oxide Peroxide.

Reacting praseodymium(IV) oxide with oxygen at 27GPa in a diamond anvil cell yielded the oxide peroxide Pr2IV(O2)O3, which was characterized by single crystal X-ray diffraction on multi-grain samples, Raman spectroscopy and quantum theoretical calculations at various pressure points. The presence of tetravalent praseodymium ions is supported by electronic structure calculations, showing a band gap of ca. 1.5eV, which is consistent with the anticipated chemical model of an ionic solid. Pr2(O2)O3 thus far represents the most oxygen rich phase of any binary compound of a lanthanoid and oxygen and is the first example of a peroxide anion next to Pr4+. Additionally, these results demonstrate that instead of oxidizing the praseodymium ions past their +IV oxidation state, oxygen undergoes a comproportionation to form peroxide anions. Direct oxidation of the oxide anions by Pr4+‑ions was ruled out by a control experiment in argon instead of oxygen, where no oxidation of oxide ions was observed.

Influence of the Carboxylates in the 3D Pb(II) Based Catalysts on the Electrochemical Oxygen Evolution Reaction.

The Oxygen Evolution Reaction (OER) is considered to be one of the important processes for energy storage and conversion applications. However, due to its sluggish kinetics it becomes extremely crucial to design and develop cost-effective, stable and highly efficient electrocatalysts. Herein, we report two lead(II)based coordination polymers (CPs) {[Pb2(TPBN)(TDC)2].2H2O}n (CP1), and {[Pb2(TPBN)(FDC)2]}n (CP2) synthesized via self-assembly at ambient conditions in good yields (where TPBN= N,N',N‴,N‴'-tetrakis-(2-pyridylmethyl)-1,4-diaminobutane, H2TDC= 2,5-2,5-thiophenedicarboxylic acid, and H2FDC = 2,5-furandicarboxylic acid. Their 3D structures were determined by Single-crystal X-ray diffraction (SCXRD) studies. The bulk purity and thermal stability of CP1 and CP2 were studied by powder X-ray diffraction studies and thermogravimetric analysis, respectively. Both the CPs showed remarkable catalytic activity for the OER. With a current density of 15 mAcm-2, for both CP1 and CP2, overpotentials of 570 mV and 630 mV with tafel slope values of 112 mV dec-1, and 178 mV dec-1 respectively for CP1 and CP2 in 1.0 M alkaline (KOH) solution was obtained. It is notable that the difference in their catalytic performance - CP1 is better than CP2, can be attributed to the subtle single heteroatom in the dicarboxylate ring (S in thiophene and O in furan, respectively).

Derailment of the Biosynthesis via an Acid-Mediated Intramolecular Cyclo-rearrangement Leads to a Novel Cytochalasin Skeleton.

Cytochalasins are notable for their structural diversity and broad range of biological activities. The gene cluster responsible for the biosynthesis of cytochalasins bearing diverse polycycles was identified in Phomopsis sp. DHS-48. Characterization of the cluster indicated that only the 5/6/11-tricycle can be biosynthetically produced. The chemical space of cytochalasins was expanded by acid-mediated intramolecular cyclo-rearrangement of the 5/6/11-tricycle, and three new cytochalasins, phomoparagins D-F (13, 17, and 18, respectively), with diversified polycycles were obtained, among which compound 13 featured an unprecedented 5/6/5/7/6-pentacycle. Their structures and absolute configurations were established by spectroscopic analysis (1D, 2D NMR), electronic circular dichroism calculations, and a single-crystal X-ray diffraction experiment. The compounds inhibited the growth of HeLa and RKO cell lines with IC50 values ranging from 0.8 to 47.3 μM. Cytoskeleton staining experiments and molecular docking models revealed that compound 13 showed cytotoxicity by targeting F-actin.

Synthesis, characterization and computational studies of the triangle shape complex of silver nitrate with 2-amino-1,3,4-thiadiazole

A new mononuclear salt-like silver(I) complex [AgL3]NO3 (Complex 1), which was readily fabricated from 2-amino-1,3,4-thiadiazole (L), is reported. Complex 1 was analyzed by elemental analysis, FT-IR and UV–vis spectroscopy, and single crystal X-ray diffraction. Intermolecular contacts for the cation [AgL3]+ in the crystal structure of Complex 1 were examined using the Hirshfeld surface analysis. The DFT-based calculations were additionally applied to reveal electronic features of Complex 1. The molecular structure of Complex 1 exhibits a mononuclear planar cation [AgL3]+ of the triangle shape with three ligands L being monocoordinated through thiadiazole the nitrogen atom, located at the third position. Two cations [AgL3]+, which, in turn, are stabilized by three NH⋯N hydrogen bonds, are stacked through a rich variety of noncovalent interactions formed by the thiadiazole π-system, yielding a supramolecular dimer {[AgL3]2}2+. These dimers are linked through Ag⋯Ag interactions with the formation of a 1D supramolecular cationic pillar {[AgL3]n}n+. A solution of Complex 1 in EtOH absorbs in the UV region due to intraligand transitions within L. Theoretical calculations revealed a strong electrophilic nature of the optimized structure of Complex 1.

A doubly Phenoxyacetate-bridged dinuclear manganese(II) complex with 1,10-Phenanthroline: Synthesis, 1-D supramolecular structure, Hirshfeld surface analysis, magnetic and theoretical studies

We report herein the synthesis and characterization of [Mn2(POA)2(Phen)4](BF4)2·H2O, 1 where POA = phenoxyacetate; Phen = 1,10-phenthroline, respectively. The crystalline complex was obtained via slow evaporation at room temperature and characterized by single crystal X-ray diffraction. FTIR and UV–vis spectroscopy were utilized to elucidate the structure of the new compound. Complex 1 crystallizes in the monoclinic crystal system with space group P21/n. Hirshfeld surface analysis revealed various intermolecular interactions in the crystal lattice. Quantum Theory of Atoms in Molecules (QTAIM), Reduced Density Gradient (RDG), and Natural Bond Orbital (NBO) analyses were employed to investigate the diverse non-covalent interactions stabilizing the crystal structure. In complex 1, the BF4− counterion plays a crucial role in crystal assembly through a network of F···H C interactions with varying strengths governed by the interaction angle and consequent ellipticity. Additionally, B − F···π interactions were observed. Other interactions include weak-to-medium hydrogen bonds and π-interactions (CH···π and π···π) within the asymmetric units and dimers extracted from the unit cell. Notably, unconventional interactions were identified and characterized in complex 1, which is C H···π interactions with the σ(CH) orbital donating to an empty p orbital in the asymmetric unit of 1. Variable-temperature magnetic susceptibility data disclosed the occurrence of weak antiferromagnetic coupling within the doubly bridged manganese(II) core with a J value of – 2.11 cm−1.

Diamagnetic, binary Sulfide Ba3Sc2S6 – with Infinite [ScS6/2] Chains as structural Element

The ternary sulfide, Ba3Sc2S6, was synthesized by the conventional high-temperature solid-state technique in an inert atmosphere, utilizing sealed silica ampules with low internal pressure of Ar gas. The crystal structure was determined by single crystal X-ray diffraction and can be described by a trigonal crystal lattice with rhombohedral symmetry, Rc (No. 167), with powder diffraction unit cell parameters a = 12.0402(1) Å and c = 13.3893(2) Å. The compound crystallizes with the K4CdCl6-type structure, which has been used to describe homologous sulfides. This crystal structure shares features with the 2H perovskites but contains infinite 1D chains, Niggli notation , consisting of alternating, distorted octahedra and trigonal prisms connected by face-sharing. Ba3Sc2S6 is diamagnetic, as determined from magnetic susceptibility measurements. UV-Vis spectroscopy data suggest a direct bandgap of about 2.9 eV. Further, DFT calculations reveal a band gap of about 1.8 eV and 2.9 eV using the PBE and the HSE06 functional, respectively, of which the latter agrees perfectly with UV-Vis observations.

The role of Li⋯F interactions in lithium and heterobimetallic lithium–magnesium complexes of the hexafluoroisopropoxide anion

As part of ongoing investigations of battery electrolytes and additives based on derivatives of 1,1,1,3,3,3-hexafluoroisopropanol, the solvent-free hexameric precursor [Li(μ3-OCH(CF3)2)]6 (1) was isolated and characterised by single-crystal X-ray diffraction and found to possess a ring-stacked hexagonal prismatic Li6 arrangement supported by Li⋯F interactions. To explore the behaviour of this fluoroalkoxide ligand further, the lithium magnesiate complexes [Li2(thf)4Mg(μ2-OCH(CF3)2)4] (2) and [Li3(thf)2(nBuMg)(μ3-OCH(CF3)2)4] (3) were also obtained; 2 from the reaction of the fluorinated alcohol with a 2:1 mixture of nBuLi:nBu2Mg, and 3 from the reaction of the alcohol with a 1:1 mixture of nBuLi:nBu2Mg. The structure of 3 is of particular interest, being based on a Li3MgO4 heterocubane arrangement which possesses a highly unusual 3:1 Li:Mg stoichiometry. The solid-state structures of 1–3 illustrate some of the range of vastly different geometries possible for s-block metal alkoxides and highlight the potential importance of Li⋯F interactions in molecular stabilisation.

Synthesis and diverse crystal packing in o-, m- and p-bis(carbonylthioureido)benzenes containing bisferrocenes.

Three bisferrocene-based bis(acylthiourea) positional isomers, namely, 1,2-bis(ferrocenylcarbonylthioureido)benzene (1), 1,3-bis(ferrocenylcarbonylthioureido)benzene (2) and 1,4-bis(ferrocenylcarbonylthioureido)benzene (3), all [Fe2(C5H5)2(C20H16N4O2S2)], have been synthesized via facile nucleophilic addition reactions of 2.3 equivalents of ferrocenoyl isothiocyanate with o-, m- and p-phenylenediamine, respectively. The structures of the three new synthesized isomers were fully characterized by 1H NMR, 13C NMR, IR and UV-Vis spectroscopy, elemental analyses and cyclic voltammetry. In addition, the structures of acetone monosolvated compound 1 (1·CH3COCH3), as well as compounds 2 and 3, have been determined by single-crystal X-ray diffraction. A combination of intermolecular N-H...S and C-H...S hydrogen bonds connects the components of compound 1·CH3COCH3 into infinite helix chains. Two pairs of different N-H...S and C-H...S intermolecular hydrogen bonds, as well as N-H...O and C-H...π co-operating interactions, link the molecules of compound 2 into a two-dimensional network. In contrast, compound 3 displays a one-dimensional double-chain array via two intermolecular C-H...S hydrogen bonds. Therefore, the three reported positional isomers present unique individual crystal assemblies.

The investigation on the synthesis, characterization and anticancer activity of Ru-based chelating diphosphine ligand compounds

Compound trans-[RuIII(dmpe)2Cl2]2(PF6)2 (2) (dmpe = 1, 2 - bis (dimethylphosphino) ethane) was obtained by directly reaction of trans-[RuII(dmpe)2Cl2] (1) with [Cp2FeIII(PF6)]. trans-[RuIII(dmpe)2Cl2]2(FeIIIX4)2 (X = Cl, 3; X = Br, 4) were prepared by reaction of compound 1 with FeX3 (X = Cl, Br), respectively. Compounds 2-4 were characterized by IR, electronic absorption spectra, elemental analysis and Single-crystal X-ray diffraction, respectively. Single-crystal X-ray diffraction studies indicate that the ruthenium atoms in compounds 2-4 all define a slightly distorted octahedron with a [RuP4Cl2] coordination core, and the iron atoms in anion FeX4− of compounds 3 and 4 displays the expected tetrahedron with a [FeX4]− coordination core. Both metal-to-ligand charge-transfer (MLCT) and ligand-to-metal charge-transfer (LMCT) transitions exhibit in the lectronic absorption spectra of compounds 2-4. The in vitro activity of compounds 1-4 was evaluated in A549 and HeLa as well as MCF7 cell lines. The relative cell viability of compounds 2-4 on A549, HeLa and MCF7 cancer cells is in the order of 2>3>4 >1 by CCK-8 method. Compounds 2-4 have better activity than that of cisplatin in higher concentration, especially compound 2.

Zhonghongite, Cu29(As,Sb)12S33, a new mineral from the high-sulfidation vein of Jiama porphyry system, Tibet, China

Abstract Zhonghongite (IMA2023-046), ideally Cu29(As,Sb)12S33, is a new mineral discovered in the high-sulfidation vein of the Jiama deposit (E 91°45′, N 29°42′), southern Tibet, China. It forms complex intergrowths with watanabeite and tennantite-tetrahedrite, creating veined or massive aggregates ranging from millimeters to centimeters. Single crystals of zhonghongite are anhedral, and their sizes range from several micrometers to ∼100 μm. The mineral is gray with a black streak and metallic luster. It is brittle, with uneven fractures, and has a calculated density of 4.925 g/cm3. The average values of electron microprobe analyses (wt%) are: Cu 42.19, As 11.11, Sb 16.09, S 25.45, Hg 3.73, Mn 0.67, and Te 0.28. The empirical formula, based on 33 sulfur apfu, is (Cu27.60Hg0.77Mn0.51Fe0.07Ag0.02)Σ28.97(As6.16Sb5.49Te0.09)Σ11.74S33. In zhonghongite, the substitution of Sb for As is limited, with the atomic ratio of As/(As+Sb) ranging from 0.457 to 0.629. Hg, Mn, and Fe, with minor Cu, are divalent and serve for charge balance. Zhonghongite is orthorhombic, space group F2mm (42), a = 10.37741(5) Å, b = 14.69821(9) Å, c = 36.7645(2) Å, and V = 5607.66(5) Å3. The crystal structure was solved and refined by single-crystal X-ray diffraction with a final R1 = 0.0235 for 27 028 (2467 unique) reflections. It is composed of individual AsS3 tripyramids and clustered As4S7 tripyramids, CuS4 tetrahedra, and CuS3 planar triangles, connected through corner S atoms in tetrahedral coordination and octahedral coordination with Cu and/or As. The structure is a derivative of a tetrahedrite-type structure. Zhonghongite was formed under high-temperature conditions and is classified as an intermediate-sulfidation state mineral.

Bioactivity-guided isolation of potent inflammasome and mitochondria damage inhibitory diterpenoids from Orthosiphon wulfenioides.

Orthosiphon wulfenioides is a medicinal plant to treat arthritis, vascular inflammation, edema, and dyspepsia. To explore the anti-inflammatory components and their mechanism of action, 12 previously undescribed highly oxidized diterpenes, wulfenioidones L-W (1-12), were isolated from O. wulfenioides by bioactivity orientation. Their structures were elucidated using HRESIMS, NMR, specific rotation, single-crystal X-ray diffraction, and ECD spectra analysis. Compounds 1-4 exhibited significant inhibition on LDH release by preventing macrophage J774A.1 pyroptosis. Compound 1 showed the most potent inhibitory effect with an IC50 value of 5.81μM. It was revealed in the Western blot experiment that compound 1 not only significantly and dose-dependently decreased the activation of CASP1 and IL-1β, but also prevented GSDMD-FL from splitting into GSDMD-NT, the membrane pore-forming protein to release inflammatory factors, thus blocking the extracellular release of IL-1β. More interestingly, compound 1 not only blocked the activation of NLRP3 inflammasome, but also strikingly enhanced the orange fluorescence of JC-1 aggregates, thus showing the activity of maintaining mitochondrial membrane potential and reversing mitochondria damage.

Positively-charged, chalcone-hydroxypyrone hybrid ruthenium(II)-arene complexes functionalized with ethacrynic acid: Synthesis, characterizaion, and antitumor effect

A new family of ethacrynic acid-functionalized, chalcone-hydroxypyrone hybrid ruthenium(II)-arene complexes (4a-4e) have been designed, synthesis and fully characterized by 1H and 13C NMR, ESI-MS, elemental analysis, and melting point tests. The molecular structure of 3a, one of the precursor complexes, has been determined by single-crystal X-ray diffraction. The cytotoxicity of the obtained complexes toward human cancer cell lines such as HeLa, MGC803, A549, MDA-MB-231, and MCF-7 cells have been investigated by MTT assay. Whereas complexes 4d and 4e showed significantly higher cytotoxicity than cisplatin (the positive control group) and complexes 3a-3e. Moreover, complexes 4d and 4e exhibited a certain selectivity (selectivity index: 7.33 and 7.57) toward MCF-7 cells over MCF-10a normal cells. Glutathione S-transferases (GSTs) activity assay indicate that complexes 4d and 4e exhibited higher GST inhibitory activity than ethacrynic acid (EA, the best characterized GST inhibitor), consistent with their higher cytotoxicity. Further mechanistic studies showed that 4e-induced cell apoptosis may be aroused by the production of ROS, the loss of mitochondrial membrane potential and G2/M phase cell arrest in MCF-7 cells. In addition, the in vivo antitumor effect study on the xenograft mouse models of MCF-7 cells reveal that complex 4e significantly inhibited tumor growth with a higher inhibition efficiency of 68.80 %, in comparison with the groups treated with cisplatin (59.25 %). These results highlight the strong possibility to develop positively-charged, chalcone-hydroxypyrone hybrid ruthenium(II)-arene complexes funcionalized with GST inhibitor as promising anticancer agents.

Nidustrin A, cysteine-retained emestrin with a unique 18-membered macrocyclic lactone from the endophytic fungus Aspergillus nidulans.

Nidustrin A (1), the first cysteine-retained emestrin featuring a unique sulfur-containing 18-membered macrocyclic lactone, along with four biogenetically related compounds (2-5), and one known analogue secoemestrin C (6), were isolated from the large-scale culture of Aspergillus nidulans, an endophytic fungus derived from the Whitmania pigra. Compounds 2 and 3 represent the second examples of noremestrin besides the previously reported noremestrin A, and the single crystal X-ray diffraction analysis of compound 2 provided solid evidence for the intriguing skeleton of noremestrin. Their structures were determined by extensive spectroscopic data, electronic circular dichroism calculations, and single-crystal X-ray diffraction. Compounds 2-4 exhibited inhibitory activity against concanavalin A-induced T lymphocyte proliferation with IC50 values from 2.95 to 24.5μM, respectively. Compound 4 could protect the liver from hepatocyte apoptosis in ConA-induced liver injury and showed moderate cytotoxic activities with IC50 values ranging from 3.26 to 15.70μM.

A theoretical investigation into the solvent effect on crystal morphology of Nintedanib Esylate by molecular dynamic simulations and experiments

Solvent effects play a crucial role in determining the crystal structure of substances obtained from solution. Choosing the appropriate solvent system is vital for the formation of active pharmaceutical ingredients with optimal crystallization characteristics. In this work, the crystal morphology of Nintedanib Esylate under 10 pure solvent conditions was explored using molecular dynamic simulations and experiments. Single crystals of Nintedanib Esylate were prepared by slow evaporation crystallization, and the single crystal structure of Nintedanib Esylate obtained in methanol solvent was determined using single-crystal X-ray diffraction. The results indicated that the crystal form of Nintedanib Esylate was consistent throughout the study. Through structural analysis of the single crystal, it was determined that nintedanib ethosylate is a channel-type hemihydrate with a porosity of 14.8%. The molecular connectivity sites within the crystal were analyzed, and the periodic arrangement trends of the molecules within the nintedanib ethosylate crystal were explored through 2D and 3D structural diagrams. Hirshfeld surface analysis was used to investigate the intermolecular interactions in the crystal structure. The results showed that there are five main types of interactions in the nintedanib ethosylate crystal, namely H···H interactions, O···H/H···O interactions, C···H/H···C interactions, N···H/H···N interactions, and S···H interactions. Among them, H···H interactions accounted for 53.9%, while the S···H interaction was the weakest, contributing only 0.2%. The H···H interactions, representing van der Waals forces, play a dominant role in promoting the formation of the nintedanib ethosylate crystal.Based on the single crystal data of Nintedanib Esylate, the attachment energy model was used to predict the crystal morphology of NE under vacuum conditions. Five major crystal planes were identified, namely {0 0 1}, {0 1 0}, {0 1 1}, {1 0 0}, and {1 1 0}, with the {0 0 1} plane having the largest surface area, accounting for approximately 32.57% of the total crystal surface area.The modified attachment energy model was used to predict the crystal morphology of Nintedanib Esylate in different solvents. The results showed that the modified attachment energy model predictions were consistent with the crystal habits obtained by evaporative crystallization, and it was predicted that the aspect ratio of the simulated crystal habit was smallest in methanol, isopropanol, and n-propanol, and largest in n-butanol and ethanol, which can be used for further optimization of crystallization processes and solvent selection for production.The diffusion ability of solvent molecules on the crystal surface is the key factor to determine the crystal growth rate. The dominant crystal surface {0 1 0} in ethanol, isopropanol, acetone, DCM and DMF solvent systems and the dominant crystal surface {1 1 0} in n-propanol solvent system have the largest diffusion coefficients and the smallest relative growth rates.This work provides valuable insights for selecting solvents in the crystallization process of Nintedanib Esylate, with methanol, isopropanol, DCM, n-propanol, acetonitrile, and DMAC recommended based on the production conditions.

A novel cocrystal of the Zn(II) coordination molecule and the benzimidazole for efficient detection of triethylamine and antibacterial property

A new cocrystal of the Zn(II) coordination molecule and the benzimidazole (bim), [Zn(bim)(SCN)3]-[Hbim] (C10H6N5S3Zn-C7H7N2, cocrystal 1) was directly synthesized at room temperature. X-ray single crystal diffraction analysis showed that cocrystal 1 is extended into a 3D supramolecular network via hydrogen bonding and π⋅⋅⋅π stacking interactions. Information on non-covalent interactions were gathered by calculating the Hirshfeld surface and fingerprint of the crystal stacking of cocrystal 1. Photoluminescence experiments demonstrated that cocrystal 1 not only possessed good solid-state fluorescence performance but also favorable fluorescence characteristics and stability in aqueous solutions. Notably, cocrystal 1 exhibited excellent anti-interference properties, high sensitivity, high fluorescence enhancement, and low limit of detection (LOD: 59.8 μM) against triethylamine (TEA) in aqueous medium via the “Turn-On” effect. In addition, the antimicrobial properties of the cocrystal were investigated. The results of antimicrobial experiments revealed that cocrystal 1 inhibited Escherichia coli (E. coli) and Methicillin-resistant Staphylococcus aureus (MRSA). Molecular docking analysis unraveled the mode of interaction with DNA in bacteria. Cocrystal 1 is a potential multifunctional material for the preparation of TEA sensors and antimicrobial agents. Finally, the possible enhancing mechanism and potential antimicrobial mechanism were researched.

Potential COX-2 inhibitors modulating NF-κB/MAPK signaling pathways: Design, synthesis and evaluation of anti-inflammatory activity of Pterostilbene-carboxylic acid derivatives with an oxime ether moiety

In this work, a series of novel Pterostilbene–oxime ether–carboxylic acid (POC) derivatives (d1–d10, e1–e10 and 1–13) were designed, synthesized, and characterized by spectroscopic techniques. In order to further determine the absolute configuration of these compounds, one of them, compound d3, was investigated by X-ray single crystal diffraction method. d3 had a triclinic crystal with P-1 space group, and its CHCH and CHN was confirmed as E configuration. A strong hydrogen bond was formed between the hydrogen atom in CHCH moiety and the nitrogen atom in CHN moiety, which was a vital factor in the formation and stability of E configuration in the CHCH and CHN. The safety and anti-inflammatory activities of compounds (d1–d10, e1–e10 and 1–13) in vitro were evaluated. At 20 μM, compounds (d1–d10, e1–e10 and 1–13 were non-toxic and exhibited weak to strong inhibitory effects on the LPS-induced NO release. Among them, five compounds (1, 2, 7, 8 and 9) showed excellent anti-inflammatory effects with IC50 (NO) values ranging from 9.87 to 19.78 μM, as well as strong COX-2 inhibitory abilities with IC50 (COX-2) values ranging from 85.44 to 140.88 nM. Moreover, there was a rough positive correlation between their anti-inflammatory properties and the COX-2 inhibitory abilities. Compounds (1, 2, 7, 8 and 9) smoothly docked with COX-2 protein (PDB ID: 5KIR) to form stable complexes with strong hydrogen bonds, with an affinity range of −8.3 to −9.9 kcal/mol. SAR indicated that the amidation of POC at R2 position was more favorable for enhancing the compound’s biological actives than esterification. In addition, the 4-fluobenzyl substitution at R2 position of the oxime ether moiety can obviously enhance the activity of above amide derivates. Introducing acyl groups (CO(CH2)nCH3, n = 2, 4 and 6) into NH(CH2)3OH group to form ester chain is disadvantageous for activity enhancing, moreover, the longer the carbon chain, the poorer the activity. The strongest COX-2 inhibitor (IC50 (COX-2) = 85.44 ± 3.88 nM), compound 7, exerted as anti-inflammatory activities (IC50 (NO) = 9.87 ± 1.38 μM) by down-regulating the expression of COX-2 and iNOS, and modulating NF-κB/MAPK signaling pathways.

Tuning the sterics: Rh-catalyzed hydroformylation reactions with ferrocene based diphosphorus ligands

The mono- and bidentate ligands FcPPh2 (1), FcPtBu2 (2), FcPMes2 (3), Fc’(PPh2)2 (dppf), Fc’(PMes2)2 (4), Fc’(PMes2)(PPh2) (5), and Fc’(PMes2)(PtBu2) (6) (Fc and Fc’ stand for 1- and 1,1′-substituted ferrocene, respectively) were reacted with Rh(I)-precursors. Maintaining P:Rh stoichiometric ratios of 2:1, dimeric Vaska-type complexes featuring P-Rh-P bridges (7–15), and monomeric complexes with [Rh(CO)2(acac)] moieties (16–22) were obtained. Complexes 16–22 were further applied in the Rh-catalyzed hydroformylation of 1-octene, while the linear-to-branched ratio (l/b) of the formed aldehydes decreases with the increase of steric bulk at the P atoms, which was further verified by theoretical calculations. For ligands 3–5, activation of the C–H bonds of the o-CH3 units of the mesityl substituent occurred with Rh(I), forming complexes with rare five-membered [C3PRh(III)] rings (10, 18a, 20 and 21a). Complexes 8, 10, 11, 13, 15 and 17 were unambiguously characterized by means of single crystal X-ray diffraction.

Synthesis, single crystal investigations, DFT studies, biological activities, DNA cytotoxicity and molecular docking studies of copper(II) complex derived from the new o-vanillin Schiff base ligand

A novel Schiff base derivative, (E)-N’-(2-hydroxy-3-methoxybenzylidene)-2-phenylacetohydrazide (HMPH, H2L), and its Cu(II) complex were synthesized through the direct condensation of o-vanillin with phenylacetichydrazide in ethanol under reflux conditions. The synthesized ligand was identified usingelemental analysis, Fourier transform infrared (FTIR) and ultraviolet–visible (UV–Vis.) spectroscopy. The structures of HMPH (C16H16N2O3)2 and its Cu(II) complex [Cu(L)(H2O)]·H2O (C16H16N2CuO4·H2O) were analysed by single crystal X-ray diffraction technique. The X-ray diffraction results showed that HMPH crystallised in an orthorhombic Pca21 space group with a Z value of 8, while [Cu(L)(H2O)]·H2O crystallised in a monoclinic C 2/c space group with the same z value. The Cu(II) ion is coordinated to the acetohydrazide ligands via hydrazone nitrogen, aceto oxygen (N(2) and O(1)) and hydroxyl O(2) atoms. In addition to the single crystal structures of HMPH and [Cu(L)(H2O)]·H2O, the optimised molecular structures, molecular electrostatic potential meps, molecular orbital energy values, and interactions between DNA bases and molecular structures are determined by DFT/B3LYP/6-311G(d, p) for HMPH and DFT/B3LYP/LanL2DZ for [Cu(L)(H2O)]·H2O. The copper complex was found to be more potent than the organic ligand in terms of antimicrobial activity, with a strong anti-biofilm effect even at low MIC values. The cytotoxicity of the synthesized compounds was investigated on MDA-MB-231 cell lines. The [Cu(L)(H2O)]·H2O complex was found to be more lethal than the HMPH ligand. Furthermore, molecular docking studies of HMPH and [Cu(L)(H2O)]·H2O with P. aeruginosa ATCC27853 (PDB ID: 6P8U) were presented to explain the observed antibacterial activity and the mechanism-of-action.