Single-crystal X-ray Diffraction Research Articles

New sesquiterpenoids with neuroprotective effects in vitro and in vivo from the Picrasma chinensis

Three undescribed sesquiterpenes, designed as pichinenoid A-C (1–3), along with nine known ones (4–12) were isolated from the stems and leaves of Picrasma chinensis. The new isolates including their absolute configurations were elucidated based on extensive spectroscopic methods, single crystal X-ray diffraction, and electronic circular dichroism (ECD) experiments, as well as comparison with literature data. Structurally, compounds 1 and 2 are descending sesquiterpenes, while pichinenoid C (3) is a rare sesquiterpene bearing a 2-methylenebut-3-enoic acid moiety at the C-6 side chain. All the isolated compounds were tested for their neuroprotective effects against the H2O2-induced damage on human neuroblastoma SH-SY5Y cells, and most of them showed moderate neuroprotective activity. Especially, compounds 1, 3–5, and 7 showed a potent neuroprotective effect at 25 or 50 μM. Moreover, the neuroprotective effects of compounds 1 and 4 were tested on a 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced Parkinson's disease (PD) mouse model. Results of western blot and immunofluorescence indicated that compound 4 significantly counteract the toxicity of MPTP, and reversed the expression of tyrosine hydroxylase (TH) in substantia nigra (SN) and striatum (ST) of the mouse brain. Interestingly, western blot data suggested compound 4 also enhanced B-cell lymphoma-2 (Bcl-2) and heme oxygenase 1 (HO-1) expressions in the brain tissues from MPTP damaged mouse.

EXPERIMENTAL AND THEORETICAL INTERPRETATIONS OF STRUCTURAL, OPTICAL, MECHANICAL AND THERMAL PROPERTIES OF 2 AMINOPYRIDINIUM PHTHALATE SINGLE CRYSTALS

Nonlinear optical good quality single crystals of 2-aminopyridinium phthalate single crystals are synthesized by solution growth technique. Structural parameters are elucidated by Single Crystal X-ray diffraction method which reveals that the material crystallizes in non-centrosymmetric crystalline framework. Vibrational assignments are interpreted by Fourier Transform Infrared spectral analysis. The thermal, mechanical and laser stability are explored by TG/DTA, microhardness and Laser Damage threshold analysis. The material has good emission nature in the violet emission region. The linear optical properties are elucidated with the help of UV-visible spectral analysis. The intermolecular charge transfer interactions are analyzed by HOMO-LUMO and MESP maps by using Gaussian ’09 software program. The second harmonic generation efficiency of the synthesized material are predicted by Kurtz Perry powder technique.

Sesquiterpene coumarins with anti-vitiligo and cytotoxic activities from Ferula samarkandica

Two undescribed sesquiterpene coumarins (1–2) and eight known analogues (3–10) were isolated from the roots of Ferula samarkandica Korovin, growing in Uzbekistan. Their structures were established by comprehensive spectroscopic analysis including NMR, HRESIMS, UV and IR data. The absolute configurations were determined based on ECD calculations and confirmed by single-crystal X-ray diffraction analysis. Six compounds carrying 7′-carbonyl, 3′-carbonyl and 3′-acetoxy (4, 5, 6, 7, 9, 10) demonstrated anti-vitiligo potentials, in addition to five (4, 7, 8, 9, 10) with cytotoxic effects. Evaluation of anti-vitiligo activity in B16 cells revealed that compounds 4–7 and 9 exhibited promotion effects on melanin synthesis in B16 cells more potent than the positive control 8-methoxypsoralen (8-MOP), while 5, 7, 9 and 10 could also stimulate the tyrosinase activity superior to 8-MOP. Besides, compounds 4 and 7–10 also presented certain cytotoxic activities against HeLa, HT-29 and A549 cell lines, wherein 8 displayed a significant cytotoxicity against HT-29 cells with an IC50 value of 8.33 ± 0.34 μM.

Single Step Synthesis of gem-Dinitro Methyl-1,2,4-triazole and Its Hydroxylamine Salt: An Alternative to the FOX-7 and Other Benchmark Explosives.

gem-Dinitro methyl based high-energy-density material 5-(dinitromethylene)-4,5-dihydro-1H-1,2,4-triazole (2) and its hydroxylamine salt (4) were synthesized for the first time in a single step and characterized. Further, the structure of 2 was confirmed by single-crystal X-ray diffraction (SCXRD) studies. Interestengly, both the compounds show excellent density (> 1.83 g cm-3), detonation velocity (> 8700 m s-1), pressure (> 30 GPa) and are insensitive toward mechanical stimuli such as impact and friction sensitivity. Considering their synthetic fesibility and balanced energetic performance, compounds 2 and 4 show future prospects as potential next-generation energetic materials for the replacenent of many presently used benchmark high energy density materials such as RDX, FOX-7 and highly insensitive H-FOX.

Applicability of the Zintl Concept to Understanding the Crystal Chemistry of Lithium-Rich Germanides and Stannides.

With this contribution, we take a new, critical look at the structures of the binary phases Li5Ge2 and Li5Sn2. Both are isostructural (centrosymmetric space group R3̅m, no. 166), and in their structures, all germanium (tin) atoms are dimerized. Application of the valence rules will require the allocation of six additional valence electrons per [Ge2] or [Sn2] unit considering single covalent bonds, akin to those in the dihalogen molecules. Alternatively, four additional valence electrons per [Ge2] or [Sn2] anion will be needed if homoatomic double bonds exist, in an analogy with dioxygen. Therefore, five lithium atoms in one formula unit cannot provide the exact number of electrons, leaving open questions as to what is the nature of the chemical bonding within these moieties. Additionally, by means of single-crystal X-ray diffraction, synchrotron powder X-ray diffraction, and neutron powder diffraction, we established that the Li and Sn atoms in Li5Sn2 are partially disordered, i.e., the actual chemical formula of this compound is Li5-xSn2+x (0 < x < 0.1). The convoluted atomic bonding in the case where tin atoms partially displace lithium atoms results in the formation of larger covalently bonded fragments. Our first-principle calculations suggest that such disorder leads to electron doping. Contrary to that, both experimental and computational findings indicate that in the Li5Ge2 structure, the [Ge2] dimers are slightly oxidized, i.e., hole-doped, as a result of approximately 30% vacancies on a Li site, i.e., the actual chemical formula of this compound is Li5-xGe2 (x ≈ 0.3).

Highly Selective Ratiometric Sensors for Pb2+ Based on Luminescent Zn(II)-Coordination Polymers with Thiophenedicarboxylate. Crystal Structures and Spectroscopic Studies.

The development of luminescent coordination polymers for the selective sensing of Pb2+ in water constitutes an active area of research that impacts analytical, environmental, and inorganic chemistry. Herein, two novel water-stable 2D Zn-coordination polymers {[Zn2(H2O)2(tdc)2(bpy)]·(H2O)}n 1 and [Zn(tdc)(tmb)]n 2 (tdc = thiophenedicarboxylate; bpy = 4,4'-bipyridine and tmb = 4,4'-trimethylenebipyridine) were synthesized, structurally determined by single crystal X-ray diffraction, and studied in-depth as luminescent sensors for a series of cations (Ca2+, Mg2+, Mn2+, Fe2+, Co2+, Ni2+, Cu2+, Zn2+ Cd2+, Hg2+ and Pb2+) in 20% aqueous ethanol. These Zn-polymers possess photostability in 20% aqueous ethanol with a strong emission at 410 upon excitation at 330nm and quantum yields of around Φ = 0.09. Under these conditions, Pb+2 can be efficiently sensed with polymer 2 through a fluorescent ratiometric response with selectivity over common interfering metal ions such as Cu2+, Cd2+ and Hg2+ in the micromolar concentration range (detection limit = 1.78 ± 10μM). Such selectivity/affinity of Pb2+ over Hg2+ for luminescent chemosensors is still rare. On the basis of spectroscopic tools (1H NMR, far ATR-IR, PXRD), the X-ray crystal structure of 2, and Scanning Electron Microscopy with Energy-Dispersive X-ray Spectroscopic analysis, the ratiometric fluorescent response is proposed via an efficient metal-ion exchange driven through interactions between thiophenedicarboxylate rings and Pb2+ ions. The use of flexible luminescent Zn-coordination polymers as sensors for selective and direct detection of Pb2+ in aqueous media has been unexplored until now.

Cyanide Addition to Diiron and Diruthenium Bis-Cyclopentadienyl Complexes with Bridging Hydrocarbyl Ligands

We conducted a joint synthetic, spectroscopic and computational study to explore the reactivity towards cyanide (from Bu4NCN) of a series of dinuclear complexes based on the M2Cp2(CO)3 scaffold (M = Fe, Ru; Cp = η5-C5H5), namely [M2Cp2(CO)2(µ-CO){µ,η1:η2-CH=C=CMe2}]BF4 (1Fe-Ru), [Ru2Cp2(CO)2(µ-CO){µ,η1:η2-C(Ph)=CHPh}]BF4 (2Ru) and [M2Cp2(CO)2(µ-CO){µ-CN(Me)(R)}]CF3SO3 (3Fe-Ru). While the reaction of 1Fe with Bu4NCN resulted in prevalent allenyl deprotonation, preliminary CO-NCMe substitution in 1Ru enabled cyanide addition to both the allenyl ligand (resulting in the formation of a h1:h2-allene derivative, 5A) and the two metal centers (affording 5B1 and 5B2). The mixture of 5B1-2 was rapidly converted into 5A in heptane solution at 100 °C, with 5A being isolated with a total yield of 60%. Following carbonyl-chloride substitution in 2Ru, CN− was incorporated as a terminal ligand upon Cl− displacement, to give the alkenyl complex 6 (84%). The reactivity of 3Fe and 3Ru is strongly influenced by both the metal element, M, and the aminocarbyne substituent, R. Thus, 7aRu was obtained with a 74% yield from cyanide attack on the carbyne in 3aRu (R = Cy, cyclohexyl), whereas the reaction involving the diiron counterpart 3aFe yielded an unclean mixture of the metastable 7aFe and the CO/CN− substitution product 8aFe. The cyano-alkylidene complexes 7aRu (R = Cy) and 7bFe (R = Me) underwent CO loss and carbene to carbyne conversion in isopropanol at 60–80 °C, giving 8aRu (48%) and 8bFe (71%), respectively. The novel compounds 5A, 5B1-2, 6 and 7aRu were characterized by IR and NMR spectroscopy, with the structure of 7aRu further elucidated by single crystal X-ray diffraction analysis. Additionally, the DFT-optimized structures of potential isomers of 5A, 5B1-2 and 6 were calculated.

Atomically Precise Chiral Metal Nanoclusters for Circularly Polarized Light Detection.

Circularly polarized light (CPL) detection is of great significance in various applications such as drug identification, sensing and imaging. Atomically precise chiral metal nanoclusters with intense circular dichroism (CD) signals are promising candidates for CPL detection, which can further facilitate device miniaturization and integration. Herein, we report the preparation of a pair of optically active chiral silver nanoclusters [Ag7(R/S-DMA)2(dpppy)3] (BF4)3 (R/S-Ag7) for direct CPL detection. The crystal structure and molecular formula of R/S-Ag7 clusters are confirmed by single-crystal x-ray diffraction and high-resolution mass spectrometry. R/S-Ag7 clusters exhibit strong CD spectra and CPL luminescence both in solution and solid states. When used as the photoactive materials in photodetectors, R/S-Ag7 enables effective discrimination between left-handed circularly polarized and right-handed circularly polarized light at 520 nm with short response time, high responsivity and considerable discrimination ratio. This study is the first report on using atomically precise chiral metal nanoclusters for CPL detection.

Solvent-controlled structural variation of two Cd(II) compounds derived from thiophene dicarboxylate and 4-imidazol-1-yl-pyridine mixed ligands

Two solvent-controlled Cd(II) compounds, formulated as {[Cd2(Htdc)4(µ-imyp)(H2O)4]} (1), [Cd2(µ 2-tdc)2(µ-imyp)(DMF)2(H2O)2]n (2) (H2tdc= 2,5-thiophenedicarboxylic acid, imyp = 4-imidazol-1-yl-pyridine and DMF = N,N-dimethylformamide) have been synthesized by reactions of Cd(NO3)2·4H2O and H2tdc with imyp in different solvents, respectively. Both compounds were then characterized by single-crystal X-ray diffraction and other physicochemical methods. In 1, partially deprotonated Htdc− anion as terminal ligand and µ-imyp ligand connect Cd2+ ions to generate a discrete structure. In 2, completely deprotonated µ 2 – tdc2− anions and µ-imyp ligand link Cd2+ ions into a 1D double chain structure. Both compounds display 3D supramolecular structures through hydrogen bonding interactions. The results provided interesting insights into solvent effects on the structural formation of compounds 1 and 2. In addition, the solid-state photoluminescent properties of compounds 1 and 2 were also investigated. Two solvent-controlled Cd(II) compounds have been synthesized by reactions of Cd(NO3)2·4H2O and 2,5-thiophenedicarboxylic acid with 4-imidazol-1-yl-pyridine in the different solvents. One compound is a discrete structure, while the other compound has a 1D double chain structure. The results provided interesting insights into solvent effects on the structural formation of compounds.

Optical Upconversion in Mononuclear Lanthanide Co-Crystal Assemblies.

In this work, we developed two kinds of co-crystal assemblies systems, consisting of discrete mononuclear Yb3+ and Er3+ and mononuclear Yb3+ and Pr3+, which can achieve Er3+ and Pr3+ upconversion luminescence, respectively, by Yb3+ sensitization under 980 nm excitation. The structure and composition of two co-crystal assemblies were determined by single crystal X-ray diffraction. By investigation of the series of two assemblies, respectively, it is found that the strongest upconversion luminescence is both obtained when the molar ratio of Yb3+ and Ln3+ (Ln=Er or Pr) is 1 : 1. The energy transfer mechanism of Er3+ assemblies is determined as energy transfer upconversion, while that of Pr3+ assemblies is determined as energy transfer upconversion and cooperative sensitization upconversion. This is the first example of Pr3+ upconversion luminescence at the molecular dimension at room temperature, which enriches the research in the field of upconversion luminescence with lanthanide complexes.

Crystal Structures, Molecular Docking and In Vitro Investigations of Two 4-Substituted 2-(5,5-dimethyl-3-styrylcyclohex-2-enylidene)malononitrile Derivatives as Potential Topoisomerase II Inhibitors

Type II topoisomerases (TOP2s) play a key role in altering the DNA topology by transiently cleaving both strands of a DNA duplex. Therefore, increased TOP2 activity is associated with many cancers. Herein, we present the synthesis, structural characterization, virtual screening, and structural exploration, as well as evaluation of the antiproliferative effects of two new 4-substituted 2-(5,5-dimethyl-3-styrylcyclohex-2-enylidene)malononitrile derivatives with potential application in the drug design of isoform-specific TOP2 inhibitors. Both compounds 1 and 2 were verified by ESI-TOF-MS, NMR, and single-crystal X-ray diffraction (SCXRD) analysis. Furthermore, we applied our recently proposed SCXRD/HYdrogen DEsolvation (HYDE) technology platform in order to perform molecular modeling, virtual screening, and structural exploration with 1 and 2. For this purpose, we used the crystal structure of human TOP2β complexed to DNA and the anticancer drug etoposide. Moreover, we further evaluated the antiproliferative activity of 1 and 2 on human hepatocarcinoma HepG2 cells and compared the observed effects with those of the reference hTOP2β inhibitor etoposide. Based on the obtained results, compounds 1 and 2 showed a virtually higher binding affinity (Ki HYDE values) over etoposide towards hTOP2β but lower antiproliferative activity compared to those of etoposide.

Novel Salts of Heterocyclic Polyamines and 5-Sulfosalicylic Acid: Synthesis, Crystal Structure, and Hierarchical Supramolecular Interactions

A series of novel salts of heterocyclic polyamines with 5-sulfosalicylic acid (C4H7N4+)(C7H5O6S−)∙2(H2O) (1), (C4H6ClN4+)(C7H5O6S−)∙H2O (2), (C5H8N3+)(C7H5O6S−)∙H2O (3), (C5H7N6+)(C7H5O6S−)∙H2O (4), (C6H14N22+)(C7H4O6S2−)∙H2O (5), and (C14H19N2+)(C7H5O6S−) (6) have been successfully synthesized. Their crystal structures have been determined by single-crystal X-ray diffraction. Overall, compounds adopt a layered structure with aminium cations and 5-sulfosalicylic anions linked via water molecules. The solid-state architectures of these compounds are dominated by O(N,H)-H⋯O and N-H⋯N hydrogen bonds and stabilized by weak interconnects. C-Cl⋯π and S-O⋯π interactions, apart from π⋯π and C-H(O)⋯π, were reported. Diverse approaches were used to study the effect of substituents in the polyamines in solid-state arrangement. A Hirshfeld surface analysis, with associated 3D Hirshfeld surface maps and 2D fingerprint plots, molecular electrostatic potential, and energy frameworks were used to comprehensively investigate the nature and hierarchy of non-covalent interactions and inspect supramolecular differences. The contact enrichment ratio calculations provided deeper insight into the propensity of interconnects to influence crystal packing. The evaluation of the effects of H-bonding synthons resulting from different substituents in the polyamines on self-assemblies is also presented. In the context of crystal engineering, a specific intramolecular synthon via O-H⋯O observed in nearly all crystals can be employed in the pseudo-cyclic replacement strategy in the design of new molecules.

A Green one-pot three component synthesis of thiazolidine-2,4-dione based bisspirooxindolo-pyrrolidines with [Bmim]BF4: their in vitro and in silico anti-TB studies.

A simple and effective three-component one-pot green methodology was employed for the synthesis of a new thiazolidine-2,4-dione based bisspirooxindolo-pyrrolidine derivatives using [Bmim]BF4 ionic liquid via [3 + 2] cycloaddition reaction. It is an environmentally benign, column chromatography-free, shorter reaction time, good yield and easy product isolation method. The synthesized compounds 10a-x, were thoroughly characterized by using various spectroscopic methods like FT-IR, 1H NMR, 13C NMR, Mass spectrometry and finally by single crystal X-ray diffraction method. In vitro anti-tubercular (anti-TB) activity studies were carried out on these synthesized compounds, and they showed good to moderate anti-TB activity against Mycobacterium tuberculosis H37Rv strain. The compound 10a exhibited good anti-TB activity, with an MIC (Minimum Inhibitory Concentration) value of 12.5µg/mL, and the compounds 10m, 10o and 10r showed moderate activity with an MIC value of 25.0µg/mL. Remaining compounds exhibited poor activity against Mycobacterium tuberculosis. Ethambutol, rifampicin and isoniazid were used as standard drugs. Furthermore, in silico molecular docking experiments on the TB protein (PDB ID: 1DF7) were carried out to understand the binding interactions, and they showed least binding energy values ranging from -8.9 to -7.2kcal/mol.

Are Selenides the Same as Sulfides? Structure, Spectroscopy, and Properties of Narrow-Gap Rare-Earth Semiconductors RE2Sn(S1-xSex)5 (RE = La, Ce; x = 0-0.8).

The ternary rare-earth sulfides RE2SnS5 (RE = La-Nd) and the partial solid solutions RE2Sn(S1-xSex)5 (RE = La, Ce; x = 0-0.8) were prepared in the form of polycrystalline samples by reaction of the elements at 900 °C and as single crystals in the presence of KBr flux. They adopt the La2SnS5-type structure (orthorhombic, space group Pbam, Z = 2) consisting of chains of edge-sharing SnCh6 octahedra separated by RE atoms. Although the cell parameters evolve smoothly in RE2Sn(S1-xSex)5, detailed structural analysis by single-crystal X-ray diffraction revealed a pronounced preference for the Se atoms to occupy two out of the three chalcogen sites, which offers a rationalization for why the all-selenide end-members RE2SnSe5 do not form. Solid-state 119Sn NMR spectra confirmed the nonrandom distribution of SnS6-nSen local environments, which could be resolved into individual resonances. The Raman spectra of RE2SnS5 compounds show an intense peak at 307-320 cm-1 assigned to a symmetric A1g mode, which is dominated by Sn-S bonds; the Raman peak intensities varied with Se substitution in La2Sn(S1-xSex)5. Optical diffuse reflectance spectra, band structure calculations, and electrochemical impedance spectra indicated that these compounds are narrow band gap semiconductors; the optical band gaps are insensitive to RE substitution in RE2SnS5 (0.7 eV) but they gradually decrease with greater Se substitution in RE2Sn(S1-xSex)5 (0.7-0.4 eV).

Catalytic activity of TiO2 nanoparticles in cyclization reactions for pyrazolone formation: DNA binding analysis via spectroscopy, X-ray crystallography, and molecular docking

This method of sustainable synthesis utilizes a range of aromatic/heterocyclic aldehydes, phenylhydrazine, and ethyl acetoacetates. The TiO2 nanoparticle catalyst facilitates cyclization reactions, yielding pyrazolone derivatives with exceptional efficiency (95–97 %) under reflux conditions at 80 °C. The current method achieves high yields of the corresponding cyclo-products in a short reaction time. A variety of physicochemical methods were employed to ascertain the chemical characteristics and structure of the synthesized heterocycles, and the geometrical structure of the well-crystallized compound (Z)-4-((5-bromofuran-2-yl)methylene)-5-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one was characterized by the use of single-crystal X-ray diffraction measurement. The morphology and elemental composition of TiO2 nanoparticles were examined using SEM/EDX before and after the model reaction. A drop in the Ti (titanium) signal following the reaction indicates surface alterations. The present process provides a new and improved synthesis process for the formation of pyrazolones that is more convenient, well organized in terms of good yields, a simple handling procedure, a short reaction time, and user-friendliness compared to other surviving procedures. One of the synthesized compounds, (Z)-4-((5-bromofuran-2-yl)methylene)-5-methyl-2-phenyl-2,4-dihydro-3H-pyrazol-3-one (2), exhibited significant DNA binding activity. This was further confirmed by a molecular docking study, which revealed a binding energy of −7.2 kcal/mol, and by analyzing the mode of interaction.

On-Purpose Oligomerization by 2-t-Butyl-4-arylimino-2,3-dihydroacridylnickel(II) Bromides

In this study, 2-t-butyl-4-arylimino-2,3-dihydroacridylnickel dibromides were synthesized by nickel-template one-pot condensation, and well characterized along with the single-crystal X-ray diffraction to one representative complex, revealing a distorted tetrahedral geometry around nickel. When activated with modified methylaluminoxane (MMAO), all nickel complexes exhibited high activities (up to 1.91 × 106 g mol−1 (Ni) h−1) toward major trimerization of ethylene. When activated with ethylaluminum dichloride (EtAlCl2), however, the title complexes performed good activities (up to 1.05 × 106 g mol−1 (Ni) h−1) for selective dimerization of ethylene. In comparison to analogous nickel complexes, higher activities were achieved with the substituent of t-butyl group, especially in the rare case of nickel complexes performing trimerization of ethylene.

Self-Assembly of a Water-Soluble Pd16 Square Bicupola Architecture and Its Use in Aerobic Oxidation in Aqueous Medium.

Designing supramolecular architectures with uncommon geometries has always been a key goal in the field of metal-ligand coordination-driven self-assembly. It acquires added significance if functional building units are employed in constructing such architectures for fruitful applications. In this report, we address both these aspects by developing a water-soluble Pd16L8 coordination cage 1 with an unusual square orthobicupola geometry, which was used for selective aerobic oxidation of aryl sulfides. Self-assembly of a benzothiadiazole-based tetra-pyridyl donor L with a ditopic cis-[(tmeda)Pd(NO3)2] acceptor [tmeda = N,N,N',N'-tetramethylethane-1,2-diamine] produced 1, and the geometry was determined by single-crystal X-ray diffraction study. Unlike the typically observed tri- or tetrafacial barrel, the present Pd16L8 coordination assembly features a distinctive structural topology and is a unique example of a water-soluble molecular architecture with a square orthobicupola geometry. Efficient and selective aerobic oxidation of sulfides to sulfoxides is an important challenge as conventional oxidation generally leads to the formation of sulfoxide along with toxic sulfone. Cage 1, designed with a ligand containing a benzothiadiazole moiety, demonstrates an ability to photogenerate reactive oxygen species (ROS) in water, thus enabling it to serve as a potential photocatalyst. The cage showed excellent catalytic efficiency for highly selective conversion of alkyl and aryl sulfides to their corresponding sulfoxides, therefore without the formation of toxic sulfones and other byproducts, under visible light in aqueous medium.

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 in size. The single crystals of zhonghongite are anhedral grains, with sizes ranging from several micrometers to approximately 100 micrometers. The mineral is gray in color with a black streak and metallic luster. It is brittle, with uneven fractures, and has a calculated density of 4.925g/cm3. The average values of electron microprobe analyses (wt.%) are as follow: 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, together 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 has been solved and refined by single-crystal X-ray diffraction with a final R1 = 0.0235 for 27028 (2467 unique) reflections. It is composed of individual AsS3 tripyramids and clustered tripyramids As4S7, 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 tetrahedrite-type structure. Zhonghongite was formed under high-temperature conditions and is classified as an intermediate-sulfidation state mineral.

Discovery of a Biocontrol Strain Trichaptum laricinum: Its Metabolites and Antifungal Activity against Pathogenic Fungus Colletotrichum anthrisci.

Finding safe and environmentally friendly fungicides is one of the important strategies in modern pesticide research and development. In this work, the antipathogenic effects of the fungus Trichaptum laricinum against the anthracnose pathogen Colletotrichum anthrisci were studied. The EtOAc extract of T. laricinum showed remarkable antifungal activity against C. anthrisci with an inhibition rate of 50% at 256 μg/mL. Bioguided isolation of the cultural broth of T. laricinum produced four new drimane sesquiterpenes, trichalarins A-D (1-4), and six other metabolites (5-10). Their structures were established by extensive spectroscopic methods, quantum chemical calculations, and single-crystal X-ray diffraction. All compounds exhibited antifungal activity against C. anthrisci with minimum inhibitory concentrations (MICs) of 8-64 μg/mL in vitro. Further in vivo assay suggested that compounds 2, 6, and 9 could significantly inhibit C. anthrisci growth in avocado fruit with inhibition rates close to 80% at the concentration of 256 μg/mL, while compounds 2 and 6 had an inhibition rate over 90% at the concentration of 512 μg/mL. The EtOAc extract of T. laricinum had no inhibitory effect on Pinus massoniana seed germination and growth at the concentration of 2 mg/mL, showing good environmental friendliness. Thus, the fungus T. laricinum could be considered as an ideal biocontrol strain, and its metabolites provided a diverse material basis for the antibiotic agents.

Trigonal Planar [PN3]4- Anion in the Nitridophosphate Oxide Ba3[PN3]O.

Nitridophosphates, with their primary structural motif of isolated or condensed PN4 tetrahedra, meet many requirements for high performance materials. Their properties are associated with their structural diversity, which is mainly limited by this specific building block. Herein, we present the alkaline earth metal nitridophosphate oxide Ba3[PN3]O featuring a trigonal planar [PN3]4- anion. Ba3[PN3]O was obtained using a hot isostatic press by medium-pressure high-temperature synthesis (MP/HT) at 200MPa and 880°C. The crystal structure was solved and refined from single-crystal X-ray diffraction data in space group R-3c (no.167) and confirmed by SEM-EDX, magic angle spinning (MAS) NMR, vibrational spectroscopy (Raman, IR) and low-cost crystallographic calculations (LCC). MP/HT synthesis reveals great potential by extending the structural chemistry of P to include trigonal planar [PN3]4- motifs.