Triclinic Space Group Research Articles

Rubidium vanadium(III) vanadyl(IV) phosphate, Rb3V3+(V4+O)(PO4)(H0.5PO4)2: crystal chemistry and low-dimensional magnetism.

In this paper, we present the synthesis and characterization of a rubidium vanadium(III) vanadyl(IV) phosphate, obtained under hydrothermal conditions. The new compound crystallizes in the triclinic space group P1̄ with the unit cell parameters a = 9.637(1), b = 12.254(2), c = 12.336(2) Å, α = 105.82(1), β = 104.81(1) and γ = 102.75(1)°. Its crystal structure was determined by single crystal X-ray diffraction. The structure of Rb3V3+(V4+O)(PO4)(H0.5PO4)2 is formed from V3+-centered octahedra sharing all oxygen vertices and one edge with phosphate tetrahedra to form ribbons parallel to the [011] direction. These ribbons are further linked via V4+O5 polyhedra in a three-periodic framework with channels running parallel to the a and b axes. Rb atoms occupy positions inside the framework channels. The title compound achieves a long range ordered antiferromagnetic state at TN = 2.1 K and formally demonstrates a high value of the magnetic frustration parameter f equal to the ratio of the Weiss and Néel temperatures |Θ|/TN = 15, which can be attributed to the reduced dimensionality of the magnetic subsystem. At T < TN, the magnetization curve exhibits the signature of the 1/3 plateau.

Synthesis, characterization and magnetic properties of a hexanuclear copper (II) complex with hydroxido, alkoxido and phenoxido bridges

A new CuII6 complex, formulated as [Cu6(L)3(µ3-OH)(H2O)(OH)(NO3)]·2H2O·7CH3OH (1) has been prepared using the symmetrical N2O3-donor Schiff-base ligand H3L = N,N′-(2-hydroxypropane-1,3-diyl)bis(2-hydroxyacetophenimine). Compound 1 has been structurally and spectroscopically characterized. Single crystal X-ray diffraction analysis reveals that 1 crystallizes in the triclinic space group P-1 and consists of a CuII6 complex where each deprotonated ligand chelates two CuII centres. Three of the six independent CuII centres are arranged in an almost equilateral triangle with double Cu-O-Cu bridges, formed by a μ3-hydroxido and phenoxido bridges. Each of the three CuII centres in the triangle is further connected to one CuII centre through a single alkoxido bridge. The magnetic properties indicate the presence of moderate and weak antiferromagnetic interactions through the double and single oxido bridges, respectively.

Alternating Cu(II) chains with bridging pyrazine, oxy- and halo-ligands

Two new Cu(II)-based structures containing alternating chains and their magnetic properties are reported. Reaction of CuBr2 and 2-aminopyridine in methanol yielded [(2-aminopyridine)μ-Br(μ-OMe)Cu]n (1) which crystallizes in the triclinic space group P-1. Cu(II) ions are linked alternately by bibromide and bi-methoxide bridges into chains parallel to the a-axis. Reaction of copper perchlorate hexahydrate with 4-pyridone and pyrazine in methanol yielded [(μ-pz)(μ-κ-O-4-pyridone)2(μ-OH)2Cu2]n(ClO4)2n (2). The Cu(II) ions are alternately linked by bihydroxide and bi-κ-O-4-pyridone species parallel to the a-axis. Those chains are further linked by bridging pyrazine molecules ∼ parallel to the b-axis, with the pyrazine molecules and bi-hydroxide bridges alternating. The net effect is a rectangular lattice where each side of the rectangle is an alternating chain. The layers are separated by perchlorate ions. Both compounds are diamagnetic at room temperature.

NH4Ca[B5O7(OH)4] H2O: A Biaxial Mixed‐Cation Pentaborate with Moderate Birefringence

AbstractAmmonium‐calcium mixed‐cation pentaborate NH4Ca[B5O7(OH)4]·H2O has been synthesized for the first time. Single‐crystal X‐ray diffraction analysis reveals that it crystallizes in the triclinic space group P‐1 with lattice parameters a = 6.7042(3) Å, b = 7.1859(3) Å, c = 10.7447(4) Å, α = 100.304(3), β = 97.774(3), γ = 96.972(3). The structure is characterized by 1D boron–oxygen chains composed of [B5O7(OH)4]3− polyanions that are further interspaced by Ca2+, NH4+ cations, along with lattice water molecules. The phase purity and thermal stability of the as‐synthesized sample were confirmed by XPRD and TG‐DSC analyses. Experimental UV–vis diffuse reflectance spectroscopy coupled with Urbach fitting indicates a direct bandgap of 4.50 eV, contrasting with theoretical calculations that suggest an indirect bandgap of 5.53 eV. Additionally, both theoretical computation and polarized light experimental test indicate that NH4Ca[B5O7(OH)4]·H2O exhibits moderate birefringence.

ZnFe2O4 Assisted Facile Green Synthesis, Structural Conformation, In-Silico and In-vitro Antimicrobial Exploration of some Piperidine Moiety Schiff's Bases

The sustainable greener synthesis and characterization of piperidine Schiff bases are described, utilizing the condensation of different aromatic aldehydes with 4-amino-N-benzylpiperidine catalyzed by ZnFe2O4 under microwave irradiation. The reaction afforded the target compounds with an excellent yield (98%), highlighting the efficiency of the catalyst. Structural elucidation was accomplished through spectral and single-crystal analysis. Characterization by FT-IR, 1H, and 13C NMR spectroscopy characterized the structure of products. Single-crystal X-ray diffraction revealed compound 3a exhibited a monoclinic crystal system with C12 space group, while compounds 3e and 3f displayed a triclinic space group of P-1 and P12/c with stable Z configurations and intermolecular hydrogen bonding interactions. Molecular docking studies exhibited the binding affinities with proteins, complemented by favorable pharmacokinetic properties. Computational approaches including DFT and Hirshfeld surface analysis were used to estimate the electronic states and molecular characteristics of the compounds (3a-f). Furthermore, the synthesized compounds also exhibited significant antibacterial and antifungal activities, revealing their potential as long-term, effective antimicrobial agents and highlighting the relevance of structure-activity connections for future research.

Hydrothermal synthesis, characterization and catalytic activities of a Keggin structure of (4,4′-bpyH2)3[PW12O40]2·3H2O and a Wells-Dawson structure of (4,4′-bpyH2)3(4,4′-bpyH)1.75[Cu(bpy)2]0.25[H2P2W18O62]2

Two novel polyoxometalates composed of heteropolytungstates, (4,4′-bpyH2)3[PW12O40]2·3H2O (1) and (4,4′-bpyH2)3(4,4′-bpyH)1.75[Cu(bpy)2]0.25[H2P2W18O62]2(2) have been synthesized under hydrothermal conditions and characterized by single crystal X-ray diffraction and TGA methods. Compound 1 crystallizes in the cubic space group Ia-3with a = 25.9356(12) Å, b = 25.936(3) Å, c = 25.936(3) Å, α = 90.00, β= 90.00, γ= 90.00 and Z = 8, and compound 2 crystallizes in the triclinic space group P-1with a = 13.5194(17) Å, b = 22.400(3) Å, c = 27.374(4) Å, α = 79.833(3), β= 77.439(3), γ= 80.213(4) and Z = 2. In addition to structural characterization, the catalytic activities of 1and 2were determined in hydrolysis reactions. In the catalytic study, starch hydrolysis reactions were performed by using hydrothermal synthesis, and starch was hydrolyzed successfully at 150 ̊C, 5 h, based on the results of Lugol's test, which highest conversion yields above 90 wt.% under optimum reaction conditions. FT-IR analysis and catalyst reusability tests were also performed for each compound. No appreciable loss was observed in activity after five reaction cycles.

Strong Antiferromagnetic Interactions in the Binuclear Cobalt(II) Complex with a Bridged Nitroxide Diradical

A binuclear cobalt–radical complex formed by the reaction of Co(hfac)2·2H2O (hfac = hexafluoroacetylacetonate) with the 2,2-bis(1-oxyl-3-oxide-4,4,5,5-tetramethylimidazolinyl) biradical (BR) has been synthesized. The complex {(hfac)CoII(BN)CoII(hfac)} crystallizes in the triclinic space group P1¯ : C34H28Co2F24N4O12, a = 11.1513(5) Å, b = 12.8362(7) Å, c = 18.2903(8) Å, α = 103.061(1)°, β = 100.898(2)°, γ = 102.250(1)°, Z = 2. The compound consists of two non-equivalent pseudo-octahedral CoII ions, each bearing two hfac ancillary ligands bridged by the tetradentate bis-nitroxide (BN). The temperature dependence of the magnetic susceptibility indicates a strong antiferromagnetic exchange between each of the Co2+ ions and the nitroxyl biradical, as well as between the spins within the bridging ligand, forming a spin-frustrated system. Micro-squid investigations, performed on a single crystal of {(hfac)CoII(BN)CoII(hfac)}, reveal a peculiarity of the M(H) graph at temperatures below 0.4 K displaying a step that is a result of ground and first excited levels mixing by the applied magnetic field due to a small energy gap between them, as inferred from ab initio calculation. The latter was also carried out for two models of mononuclear Co2+ complexes in order to obtain a set of initial parameters for fitting the experimental magnetic curves using the Phi program. Moreover, direct CAS(12,10)/def2-TZVP calculations of the magnetic dependences χT(T) and M(H) were performed, which satisfactorily reproduced the experimental ones.

Crystals of para-quaterphenyl and its trimethylsilyl derivative. I. Growth from solutions, structure and crystal chemical analysis by the Hirschfeld surface method

The results of crystal growth of para-quaterphenyl (4P) and its derivative – 4,4''-bis(trimethylsilyl)-para-quaterphenyl (TMS-4P-TMS) from solutions are presented. It has been established that TMS-4P-TMS crystals exhibit better growth characteristics compared to 4P. Parameters of phase transitions of 4P and TMS-4P-TMS in closed crucibles were refined using the method of differential scanning calorimetry. The crystal structure of TMS-4P-TMS in the triclinic space group P1 (Z = 2) has been decrypted for the first time using single-crystal X-ray diffraction and studied over a wide temperature range. Crystallographic analysis of the studied compounds in crystals was performed using the Hirshfeld surface method, and modeling of intermolecular interactions was conducted.

Synthesis and structural characterization of new perovskite phases, Ba2Bi0.572TeO6± δ and SrLa2NiFeNbO9

Ba2Bi0.572TeO6± δ and SrLa2NiFeNbO9 ceramics were prepared in polycrystalline form by conventional solid-state reaction techniques in air. The crystal structures of the title compounds were determined at room temperature from X-ray powder diffraction (XRPD) data using the Rietveld method. The Ba2Bi0.572TeO6± δ structure crystallizes in a triclinic space group I–1 with unit-cell parameters a = 6.0272(2) Å, b = 6.0367(1) Å, c = 8.5273(3) Å, α = 90.007(7)°, β = 90.061(2)°, and γ = 90.015(4)°. The tilt system of the BiO6 and TeO6 octahedra corresponds to the notation a–b–c–. The crystal structure of the SrLa2NiFeNbO9 compound adopts an orthorhombic Pbnm space group with lattice parameters a = 5.6038(5) Å, b = 5.5988(4) Å, and c = 7.9124(6) Å. The BO6 octahedra (B = Ni/Fe/Nb) sharing the corners in 3D. Along the c-axis, the octahedra are connected by O(1) atoms of (x,y,1/4) positions; while in the ab-plane, they are linked by O(2) atoms of (x,y,z) positions. The bond angle of B–O1–B is 168.7° and that of B–O2–B is 156.3°. The octahedral lattice corresponds to the tilt pattern a–a–c+; it indicates that the octahedra tilt out-of-phase along the a,b-axes and in phase along the c-axis.

Crystal structures of the (η2:η2-cyclo-octa-1,5-diene)(η6-toluene)-iridium(I) cation and μ-chlorido-iridium(III) complexes of 2-(phosphinito)- and 2-(phosphinometh-yl)anthra-quinone ligands.

When reacted in dry, degassed toluene, [Ir(COD)Cl]2 (COD = cyclo-octa-1,5-diene) and 2 equivalents of 2-(di-tert-butyl-phosphinito)anthra-quinone (tBuPOAQH) were found to form a unique tri-iridium compound consisting of one monoanionic dinuclear tri-μ-chlorido complex bearing one bidentate tBuPOAQ ligand per iridium, which was charge-balanced by an outer sphere [Ir(toluene)(COD)]+ ion, the structure of which has not previously been reported. This product, which is a toluene solvate, namely, (η2:η2-cyclo-octa-1,5-diene)(η6-toluene)-iridium(I) tri-μ-chlorido-bis-({3-[(di-tert-butyl-phosphan-yl)-oxy]-9,10-dioxoanthracen-2-yl}hydridoiridium(III)) toluene monosolvate, [Ir(C7H8)(C8H12)][Ir2H2(C22H24O3P)2Cl3]·C7H8 or [Ir(toluene)(COD)][Ir(κ-P,C-tBuPOAQ)(H)]2(μ-Cl)3]·toluene, formed as small orange platelets at room temperature, crystallizing in the triclinic space group P. The cation and anion are linked via weak C-H⋯O inter-actions. The stronger inter-molecular attractions are likely the offset parallel π-π inter-actions, which occur between the toluene ligands of pairs of inverted cations and between pairs of inverted anthra-quinone moieties, the latter of which are capped by toluene solvate mol-ecules, making for π-stacks of four mol-ecules each. The related ligand, 2-(di-tert-butyl-phosphinometh-yl)-anthra-quinone (tBuPCAQH), did not form crystals suitable for X-ray diffraction under analogous reaction conditions. However, when the reaction was conducted in chloro-form, yellow needles readily formed following addition of 1 atm of carbon monoxide. Diffraction studies revealed a neutral, dinuclear, di-μ-chlorido complex, di-μ-chlorido-bis-(carbon-yl{3-[(di-tert-butyl-phosphan-yl)-oxy]-9,10-dioxoanthracen-2-yl}hydridoiridium(I)), [Ir2H2(C23H26O2P)2Cl2(CO)2] or [Ir(κ-P,C-tBuPCAQ)(H)(CO)(μ-Cl)]2, Ir2C48H54Cl2O6P2, again crystallizing in space group P. Offset parallel π-π inter-actions between anthra-quinone groups of adjacent mol-ecules link the mol-ecules in one dimension.

Enhanced supercapacitive performance in Cu doped Sn3O4 synthesized by a simple extract route

The synthesis of nanomaterials using plant extracts is of great importance for a sustainable, chemical-free future. In this study, multivalent Sn3O4 doped with Ni and Cu were synthesized by a simple, low-cost method using Moringa oleifera leaf extract at low temperature and investigated for supercapacitor applications. Various characterizations indicate that the synthesized samples crystallize in a triclinic space group and have a larger surface area of 109.2 m2/g, which is advantageous for electron and ion transport. Electrochemical studies were carried out by cyclic voltammetry, galvanostatic charge/discharge, impedance spectroscopy and cycle life measurements in 6 M KOH electrolyte. Cu-doped Sn3O4 showed the highest capacitance of 608 C/g at a current density of 1 A/g. An asymmetric device built with it delivered an energy density of 31.5 Wh/Kg at a power density of 1400 W/Kg and retained 85 % capacity even after 6000 continuous cycles. The results show that extract-based synthesis of multivalent oxides is beneficial not only for a sustainable environment but also for achieving superior capacity.

Characterization and Solid-State UV-Vis Investigations of Photoelectrocatalytically Active La5Cl7[TeO3]4, a Mixed Anion Compound with Alternating 2D Layers of Oxygen and Chlorine.

An oxide chloride, La5Cl7[TeO3]4, was synthesized using the conventional high-temperature solid-state synthesis technique in an inert atmosphere. This compound possesses a novel crystal structure that can be described with the triclinic space group P1̅ (No. 2) and unit cell parameters: a = 7.2634(3) Å, b = 8.1241(3) Å, c = 9.1993(3) Å, α = 79.373(1)°, β = 83.599(1)°, and γ = 82.511(1)°. The preference of Te(IV) to coordinate to oxygen and direct its lone pair toward the lower charged chlorine results in 2D layers of both oxygen and chlorine, alternating along the crystallographic b-direction. Homoleptic coordination, solely to oxygen, and heteroleptic coordination to oxygen and chlorine are observed for lanthanum, forming layers connected through edge-sharing polyhedra. In the crystal structure, two distinct tellurium positions are observed, with three close Te-O distances, emphasizing an active lone pair. The compound has been investigated by solid-state UV-vis measurements, and a band gap of 3.44 eV has been determined by DFT calculations. Detailed photoelectrochemical measurements clearly indicate that the title compound is photoelectrocatalytically active, showing an n-type behavior. Raman spectroscopy confirms that complex tellurite ions are present in the crystal structure; several observed bands can be assigned to Te-O stretching, reflecting the relatively low crystallographic symmetry of the title compound.

Integrating simulated and experimental studies on novel single crystal bis(guanidininium) n-carboxylatephenylalanine towards enhanced antitumor effect

A novel organic crystal bis(guanidininium) n-carboxylatephenylalanine (GUPA) was synthesized and X-ray diffraction outcomes exposed P21, triclinic space group with cell dimensions a = 6.6492(3) Å, b = 16.2440(7) Å, c = 7.8985(3) Å, β = 0.127(2) °, V = 853.11(6) Å3, Z = 2 and possess good agreement with experimental data. Intermolecular interactions were revealed through hirshfeld and major contribution from O-H interaction confirms the presence of intermolecular hydrogen bonds. Through B3LYP algorithm with set 6–311++ G (d, p), chemical reactivity forms and molecular structure of GUPA was investigated, confirming a good stability and hard electrophilic nature. While first order hyperpolarizability value (35.37 × 10−31 esu) was indicative of good nonlinear optical material and hyperconjugate interactions and charge delocalization was further confirmed by natural bond orbitals. To further investigate the electronic properties theoretical (TD-DFT) and experimental absorption wavelengths were compared and excitation energies, oscillator strength and type of electronic transition with contributions have also been studied. The topological properties were evaluated using ELF/LOL maps and RDG with NCI were used to establish the type of interaction present in the GUPA molecular system. The anti-breast cancer effect of GUPA was computationally studied through molecular docking against p53 gene and was further investigated through in vitro MDA-MB-231 cell line studies and GUPA showed better inhibition of cancer cells and their expression.

Synthesis, characterization, and biological activity of a fresh class of sonochemically synthesized Cu2+ complexes

The synthesis and characterization of metal complexes have garnered significant attention due to their versatile applications in scientific and biomedical fields. In this research, two novel copper (Cu) complexes, [Cu(L)(L′)(H2O)2] (1) and [Cu(L)(Im)H2O] (2), where L = pyridine-2,6-dicarboxylic acid, L′ = 2,4-diamino-6-hydroxypyrimidine, and Im = imidazole, were investigated concerning their sonochemical synthesis, spectroscopic analysis, and biological activity. The complexes’ structural characterization was achieved using analytical techniques, including single-crystal X-ray structure determination, FTIR, PXRD, TGA and DTA, SEM, TEM, and EDS. Complex (1) displayed a six-coordinated Cu2+ ion, while complex (2) exhibited a five-coordinated Cu2+ ion. The crystal structures revealed monoclinic (C2/c) and triclinic (P-1) space groups, respectively. Both complexes showcased zero-dimensional (0D) supramolecular networks, primarily driven by hydrogen bonding and π–π stacking interactions, which played pivotal roles in stabilizing the structures and shaping the unique supramolecular architecture. Both complexes demonstrated significant antioxidant activity, suggesting their capability to neutralize free radicals and mitigate oxidative stress-related diseases. Hemolysis percentages were less than 2%, per the ASTM F756-00 standard, indicating non-hemolytic behavior. Low cytotoxicity was observed against fibroblast and MCF-7 cell lines. They do not exhibit antibacterial activity against Escherichia coli and Staphylococcus aureus. These findings suggest that the synthesized Cu2+‒complexes hold considerable promise for applications in drug delivery and cancer treatment. This research contributes to the advancement of supramolecular chemistry and the development of multifunctional materials for diverse scientific and medical applications.

Structure and photoluminescence properties of coordination compound [Eu2(o-MBA)6(phen)2] with high quantum yield

An europium(III) coordination binuclear compound [Eu2(o-MBA)6(phen)2] (o-MBA = ortho-methylbenzoate, phen = 1,10-phenantroline) has been synthesized and investigated by X-ray diffraction method, thermogravimetric analysis (TGA), infrared (IR) and photoluminescence (PL) spectroscopy. The single crystal X-Ray diffraction measurements show that the compound crystallizes in the triclinic centrosymmetric space group P-1. The PL excitation spectrum displays a broad band between 300 and 420 nm and a number of sharp transitions between 384 and 590 nm, which can be attributed to the Eu3+ 4f6 intra-shell excitation transitions. The complex exhibits characteristic narrow, metal-centred emission bands, which are determined by the radiative transitions of the Eu3+ ion, from the first excited non-degenerate 5D0 level to the 7FJ (J = 0–4) manifold. The compound shows intense hypersensitive transition 5D0→7F2 which dominates the PL emission spectrum. The dipole strengths of the transitions were determined from the emission spectra in terms of Judd-Ofelt (JO) intensity parameters Ωλ (λ = 2, 4). The high intensity bright-red emission of the complex can be attributed to highly polarizable ligands environment and the low site symmetry (Ci) around the lanthanide ions. We suppose that the J-mixing effect in the Eu(III) ions is responsible for enhanced peak maximum of the 5D0→7F0 transition.

Structural and LuminescentProperties of Dy(III) DopedCa0.5Bi3P2O10 Nanophosphors for Solid-State Lighting& Latent Fingerprinting Applications.

Anefficient urea-assisted SC (solution-combustion)approach was used to synthesize a novel series ofdoped Ca0.5Bi3P2O10: xDy3+ nanophosphors (0.01-0.1mol). The powdered materials were thoroughly investigated using structural and optical measures. 'Rietveld refinement'investigations found that the produced nanophosphorformed a triclinic system with the P -1 triclinic space group. An EDS (energy-dispersive spectral)study was conducted to determine the corresponding proportions of constituentelements of doped nanophosphors. The TEM (transmission electron microscopy)revealed aggregated particles with a standard size onthe nanoscale. The PLE (Photoluminescence excitation)spectrum indicates that the indicated phosphors can be stimulated by NUV (near ultraviolet)illumination sources. The Dy3+-ions undergo transitions from (4F9/2 → 6H15/2 & 4F9/2 → 6H13/2) were recognized as (PL) spectra with an excitation of 353nm revealed the presence of blue-yellow bands at 481, and 577nm, correspondingly. Further, PL data was used to determine photometric metrics such as CCT (correlated color-temperature), CC (chromaticity-coordinates (x &y)), and CP (color-purity (%)), supporting their use in solid-state lighting and latent fingerprinting applications.

2,4-Diarylpyrroles: synthesis, characterization and crystallographic insights.

Three 2,4-diarylpyrroles were synthesized starting from 4-nitrobutanones and the crystal structures of two derivatives were analysed. These are 4-(4-methoxyphenyl)-2-(thiophen-2-yl)-1H-pyrrole, C15H13NOS, and 3-(4-bromophenyl)-2-nitroso-5-phenyl-1H-pyrrole, C16H11BrN2O. Although pyrroles without substituents at the α-position with respect to the N atom are very air sensitive and tend to polymerize, we succeeded in growing an adequate crystal for X-ray diffraction analysis. Further derivatization using sodium nitrite afforded a nitrosyl pyrrole derivative, which crystallized in the triclinic space group P-1 with Z= 6. Thus, herein we report the first crystal structure of a nitrosyl pyrrole. Interestingly, the co-operative hydrogen bonds in this NO-substituted pyrrole lead to a trimeric structure with bifurcated halogen bonds at the ends, forming a two-dimensional (2D) layer with interstitial voids having a radius of 5 Å, similar to some reported macrocyclic porphyrins.

Crystal structure of hexa-glycinium dodeca-iodo-triplumbate.

The crystal structure of hexa-glycinium tetra-μ-iodido-octa-iodido-triplumbate, (C2H6NO2)6[Pb3I12] or (GlyH)6[Pb3I12], is reported. The compound crystallizes in the triclinic space group P. The [Pb3I12]6- anion is discrete and located around a special position: the central Pb ion located on the inversion center is holodirected, while the other two are hemidirected. The supra-molecular nature is mainly based on C-H⋯I, N-H⋯I, O-H⋯I and N-H⋯O hydrogen bonds. Dimeric cations of type (A +⋯A +) for the amino acid glycine are observed for the first time.

Metronidazole-Picric acid salt formation: Synthesis, characterization, Hirshfeld surface analysis, single crystal X-ray diffraction, computational studies, and molecular docking studies against Clostridioides difficile

The salt formation of metronidazole (MET) and picric acid (PA) is obtained via slow evaporation of their mixture in methanol which afforded a novel organic salt, C6H10N3O3+⋅C6H2N3O7- (METPA). The structure of METPA salt was analyzed using single crystal X-ray diffraction. METPA crystallizes in the triclinic space group P-1 with cell dimensions: a = 8.2446(1), b = 9.1843(1), c = 11.5832(2) Å, α = 106.190(1)°, β = 99.483(1)°, γ = 106.635(1)°, Volume (Å3) = 778.02(2) and Z = 2. The formation of METPA salt was analyzed by comparing the IR spectrum of MET, PA and METPA salt. In order to visualize the intermolecular interactions in the crystal of METPA salt, Hirshfeld surface analysis was employed. QTAIM calculations were performed using the AIMALL program package to estimate the strength of hydrogen bonding interactions in terms of bond critical points (BCP) and ring critical points (RCP). Molecular docking of the MET and METPA was conducted against three toxins of Clostridioides difficile such as C. difficile toxin A (TcdA), C. difficile toxin B (TcdB), C. difficile transferase (CDT). The results showed that the docking score calculated based on the knowledge-based iterative scoring function ITScore-PP indicates that METPA with higher negative value of docking score in case of all three toxins when compared to MET. This shows that the binding model of METPA salt is more favorable than MET.

Molecular structure, molecular docking, molecular dynamics simulation, and drug likeness evaluation of 3,7-dihydroxy-1,2-dimethoxyxanthone for its anticancer activity

A naturally occurring xanthone, named 3,7-dihydroxy-1,2-dimethoxyxanthone was experimentally and computationally investigated for its anticancer activity. Single crystal X-ray diffraction (XRD) analysis revealed that the compound crystallises in the triclinic space group P1. Vibrational frequencies, electronic properties, chemical reactivity descriptors, the molecular structure, and stability of the compound were investigated by DFT calculations using Gaussian 09 W program at the B3LYP/6–311+G(2d,p) level of theory. All calculations showed correlations to experimental data. Its thermodynamic parameters at various temperatures are presented. The title molecule was docked on the proteins of prostate, cervical, breast, and melanoma cancer cells, and the results showed comparable binding energies to the standard chemotherapeutic agent, doxorubicin with small differences in the range 0.2−0.7 kcal mol−1. Given that the compound showed significant potential on the proteins of prostate and cervical cancer cells, the dynamic properties of the bound state of title ligand with the two selected proteins were further examined through a 200 ns molecular dynamics simulation. The results showed relatively overall higher stability through the simulation time than the free target. All these findings were afterwards confirmed by the good in vitro inhibition activity of the compound against human prostate and cervical cancer cell lines with IC50 values of 9.55 and 9.19 µM, respectively in comparison to the standard drug, and additionally demonstrated innocuousness towards normal human kidney cancer cell lines. Moreover, the drug likeness properties indicated that the title compound has a high bioavailability, a good water solubility, a good gastrointestinal absorption, and can be easily synthesized.