Journal of Chemical Crystallography最新文献

Methyl 2,3-di-O-benzyl-α-d-(4-²H)-glucopyranoside, C₂₁H₂₅DO₆, is an intermediate used in synthesis of oligosaccharides. The hexopyranose ring has the ⁴C₁ chair conformation in the crystal structure. The exocyclic groups of the hexose sugar show for the glycosidic torsion angle ϕ =−52.8° and for the hydroxymethyl group the gauche-gauche conformation with ω = −64.7°, one of the two main orientations of the latter group in hexopyranose sugars that have the gluco-configuration, i.e., with an equatorial hydroxyl group at C4. The benzene rings of the benzyl groups are arranged with an angle of 56.9° to each other within the molecule and show intramolecular as well as intermolecular C-H···π interactions. A chain of intermolecular hydrogen bonds exists along the b-axis involving O4 and O6 atoms. The experimentally observed peak in the infrared spectrum at 2159 cm^− 1 was ascribed to the stretching of the C4–D4 bond based on DFT calculations.

Graphical Abstract

In the structure of the monosaccharide methyl 2,3-di-O-benzyl-α-d-(4-²H)-glucopyranoside, C₂₁H₂₅DO₆, the two hydroxyl groups HO4 and HO6 act as both donors and acceptors resulting in an intermolecular hydrogen bond chain along the b-axis direction.

ALZ-801 (valiltramiprosate) is an orally bioavailable, small-molecule inhibitor of β-amyloid (Aβ) oligomer formation in late-stage clinical development as a potential disease-modifying treatment for Alzheimer’s disease (AD). ALZ-801, (S)-3-(2-amino-3-methylbutanamido) propane-1-sulfonic acid, is a valine-conjugated prodrug of tramiprosate. Structural, polymorphic analysis of the active pharmaceutical ingredient (API) of ALZ-801 showed extra peaks when high throughput transmission mode XRPD analysis was utilized. After extensive investigation, the extra peaks were determined to be an artifact of transmission mode XRPD, which was not observed in either reflectance or capillary mode XRPD analyses. Reflectance mode XRPD was demonstrated as the most appropriate methodology to monitor the crystal form of ALZ-801 API. In conclusion, ALZ-801 API is a single, pure polymorph form.

Graphical Abstract

A single crystalline form of ALZ-801 is observed in a range of crystal morphologies, the risk of a change in solid form affecting the delivery of this potential new disease modifying therapy for Alzheimer’s disease is negligible

Phase light microscopy image of ALZ-801 crystal pattern 1 (single polymorph). ALZ-801 crystals occur in diverse ranges of morphologies, i.e., tetrahedron (a), bladed, needles, dodecahedron, slices(b), prismatic (c) and tabular (d) forms

In this work by means of the neutralization reaction of the N,N-dimethylbenzylamine, 3,5-dinitrobenzoic acid, 3,5-dinitrosalicylic acid and naphthalene-1,5-disulfonic acid, three bi- and tri-component crystalline salt systems are made by the gradual solvent volatilization method. The detailed features have been thoroughly conducted by the set of the analytical performances embracing the single crystal X-ray diffraction (SC-XRD), IR and EA, the melting points (m.p.s) were also measured. Their structural and supramolecular facets were analyzed in detail according to the noncovalent linkages and the supramolecular synthons. The role of the major intermolecular contacts was evaluated further by the Hirshfeld surface analysis (HSA) suite of programme for illucidating their importances. All the salts demonstrated the 3D net structures for the collective effect of the various non-covalent contacts. All contained the identical mol stoichiometry of 1:1 rate between the dmba & the number of the acidic units and embraced the N–H···O & O–H···O Hbonds together with the other non-covalent connections. Within all the salts, the respective residues are permanently tethered to each other via the energetic Hbonds belonging to the ionic N_{N,N-dimethylbenzylaminium}–O_acid fashion. Other extensive non-covalent connections of CH···O/CH₂···O/CH₃···O, C_π···π, CH···π/CH₃···π and π···π also function appreciable roles in the spatial expandings. The salts demonstrated the R₂²(4), R₂²(7), R₂²(12), R₂²(15), R₄³(11), R₄³(12), R₄⁴(20), R₄⁴(22), R₆⁵(30) and R₈⁸(44) rings. For the synergism of the traditional Hbonds and the diversified non-covalent connections, all applied the 3D appearances.

Graphical Abstract

The structures of the salts from dmba, 3,5-dinitrobenzoic acid, 3,5-dinitrosalicylic acid, and naphthalene-1,5-disulfonic acid are predominantly stabilized by the classical Hbonds together with the CH···O/CH₂···O/CH₃···O, C_π···π, CH···π/CH₃···π & π···π associates, erecting the 3D graphs.

Salt metathesis reaction between equimolar ratios of [Li{ArNC(NMe₂)Nar}(THF)] (Ar = C₆H₃Prⁱ₂-2,6) and CrCl₃ in tetrahydrofuran (THF) leads to a mono(guanidiante) chromium(III) chloride complex, [Cr{ArNC(NMe₂)Nar}Cl₂(THF)₂]. X-ray analysis confirms it to be monomeric in solid state in which guanidinate ligand is coordinated in bidentate fashion to the six coordinated Cr center. The octahedral coordination is completed by two chloride atoms and two THF molecules. The herein reported compound is the first example of monomeric chromium halides of guanidinate ligands. Hirshfeld surface analyses indicate that H∙∙∙H interactions, H∙∙∙C/C∙∙∙H and H∙∙∙Cl/Cl∙∙∙H H–bonds are the three and at times the strongest contributions for the intermolecular interactions. The title compound, [C₃₅H₅₆Cl₂CrN₃O₂], crystallized in the monoclinic space group, P2₁/n with cell parameters: a = 11.5340(7) b = 17.6830(11) c = 18.0320(11) Å, β = 92.410(5), V = 3674.5(4) A³, Z = 4.

Reaction of 1,4-bis(1H-imidazol-1-yl)benzene ligand (bib) and CuSiF₆ in water/ dimethylsulfoxide (DMSO) as the solvent mixture affords purple crystals of a metal-organic framework, 1, suitable for single crystal X-ray diffraction (SCXRD) analysis. 1 crystallizes in the triclinic P − 1 space group: a = 12.694(2) Å, b = 13.455(2) Å, c = 13.740(3) Å, α = 88.919(7)°, β = 67.864(7)°, γ = 65.029(6)°, V = 1942.9(6) ų. 1 was found to be a new phase of SIFSIX-23-Cu. Moreover, in the structure pores a cluster formed by two molecules of DMSO and ten molecules of water was identified possessing a double ice Ih-like shape.

Anthracen-9-yl(3,6-dimethoxynaphthalen-2-yl)methanone (III), affords chiral crystals belonging to P2₁2₁2₁ space group. To investigate the decisive factors of chiral supramolecular crystallisation, the crystal structural characteristics of compound III were compared with the those of two 3-aroylated 2,7-dimethoxynaphthalene homologues, the 3-benzoylated (I) and 3-(1-naphthoylated) (II) derivatives, and those of their mother skeleton molecule, 2,7-dimethoxynaphthalene. The two homologues yielded achiral crystals in P2₁/c space group and the mother skeleton afforded chiral crystal in P2₁2₁2₁ space group. The spatial features of the single molecular structure, molecular accumulation, non-covalent bonding interactions, and proximity of molecules in crystal were analysed for the four compounds. In the crystalline single molecular structure of compound III, the connection between the 2,7-dimethoxynaphthalene ring and the ketonic carbonyl moiety is nearly coplanar and the anthracene ring connects to the ketonic carbonyl moiety almost perpendicularly. In the crystalline single molecular structures of homologues I and II, the 2,7-dimethoxynaphthalene rings are bonded with larger twists to the ketonic carbonyl groups than the arene rings. In crystal packings of homologues I and II, the centrosymmetric dimeric aggregations with pairs of complementary non-classical hydrogen bonds are observed. Compound III forms two-fold helical molecular assemblies with C–H…π non-classical hydrogen bonds along the a-axis. Hirshfeld surface analysis has emphasised that these packing motifs affect molecular packing distinctively. Compound III has the largest number of molecules in close proximity. The crystal structures of the four compounds, including non-aroylated 2,7-dimethoxynaphthalene, are interpreted in terms of their potential for chiral crystal formation by considering the transition in the types and ratios of effective non-classical hydrogen bonds functioning as inter- and intramolecular modes, under the primary influence of ketonic carbonyl group participating interactions.

Graphical Abstract

The crystal structures of the 3-(9-anthroylated) 2,7-dimethoxynaphthalene and its homologues having smaller sized-aromatic ring substituents, including non-aroylated 2,7-dimethoxynaphthalene, have been interpreted in terms of their potential for chiral crystal formation by considering the transition in the types and ratios of effective non-classical hydrogen bonds functioning as inter- and intramolecular modes.

The title compound, [Ni(C₆H₈N₂)₂(C₇H₅O₄)₂] was obtained by dissolving of o-phenylenediamine (OPDA), nickel (II) sulfate and 2,4-dihydroxybenzoic acid (2,4-DHB) separately in 10 mL of ethanol (96%) and reacting with 10 mL of distilled water. The reaction mixture was stirred at room temperature and then slowly evaporated the pale green solution at 55–60 °C. The composition and crystal structure of the [Ni(C₆H₈N₂)₂(C₇H₅O₄)₂], complex was obtained at a constant temperature (30 ± 1 ºC) in 12 days. The complex is formed with two neutral bidentate OPDA ligands and two monodentate DHB ligands as [Ni(C₆H₈N₂)₂(C₇H₅O₄)₂]. The Ni atom is located at the inversion center, exhibiting a slightly octahedrally distorted coordination environment, with four nitrogen atoms of two o -phenylenediamine ligands (Ni–N) positioned in the equatorial plane and two oxygen atoms of 2,4-dihydroxybenzoic acid located in the axial plane. Here, two Ni–N bonds [Ni1 —N1 = 2.110(3), Ni1 —N1 ⁱ = 2.110(3) are exhibited the same bond length but opposite Ni–N bands are different Ni2 —N2 = 2.131(2), Ni2 —N2 ⁱ = 2.131(2)] and a longer axial two Ni—O bonds [2.136(2)]. The metal is located around the inversion center and is almost coplanar with the NiN₄ plane. In the crystal, inter-molecular hydrogen bonding interactions are observed at N1— H1..O1 and N2 — H2…O1 in the periodic network structure. The Hirshfeld surface analysis report indicates that the most important contributions to the crystal packing are H…H (44.6%), H….C/C….H (28.7%), O…H/H….O (23.7%), O…C/C….O (2.5%), C…C (1.7%), O…O(0.8%) interactions.

Graphical Abstract

The paper is designed by crystal structures of Ni(II) complex containing [Ni(C₆H₈N₂)₂(C₇H₅O₄)₂]. In continuation of our interest in the combination forms of benzene-1,2-diamine (ortho-phenylenediamine = OPDA) and 2,4-dihydroxybenzoic acid (2,4-DHB) with first-line conversion of metals, the authors considered a detailed discussion of the structure analysis of the Ni(II) complex from the mixed ligand of OPDA and 2,4-DHB using X-ray crystallographic technique

The reaction between (Me₄N)₄[Nb₆Cl₁₂(CN)₆], [Mn(salen)Cl(H₂O)] (salen = N, N’-bis (salicylidene)ethylenedi-amine dianion), and trans-1,2-bis(4-pyridyl)-ethylene (bpe) led to the formation of {[Mn(salen)(H₂O)](bpe)[Mn(salen)]}₂[Nb₆Cl₁₂(CN)₆]⋅17H₂O (1). 1 features assemblies of 4.47 nm-long molecular nanorods in each of which two [Mn(salen)]⁺ connects via one bpe linker to form a dimeric unit and two dimeric units are trans-coordinated to one [Nb₆Cl₁₂(CN)₆]⁴⁻via cyanido. Its magnetic properties and thermal stability are also reported.

Graphic Abstract

Direct Assembly of {Nb₆} Cluster Units, [Mn(salen)]⁺, and Bpe Leads To Neutral Supramolecular Nanorods of 4.47 nm long

This work is devoted to the semisynthesis of 4-allyl-2-methoxyphenyl-4-nitrobenzenesulfonate 3 from naturally occurring eugenol. The structure of the titled compound is established using IR, (¹H and ¹³C) NMR, and mass spectrometry. Single crystal X-ray diffraction is used to corroborate the structure of the compound 3. Crystallographic study shows that compound 3 crystallizes in the monoclinic system with P2₁/n as the space group. DFT studies are carried out to calculate HOMO and LUMO energies. ADMET properties, Molecular docking and dynamic simulation studies are also performed towards the SARS-CoV-2 protein.

Graphical Abstract

This paper describes a combined crystallographic and computational studies of the 4-allyl-2-methoxyphenyl-4-nitrobenzenesulfonate synthesized from naturally occurring eugenol

The synthesis of 3-methyl-4-nitro-1,1-biphenyl (3-MNB) and its crystal structure elucidated using experimental and theoretical methods has been reported in this paper. It crystallizes in the orthorhombic crystal system (space group P2₁2₁2₁) with unit cell parameters: a = 7.2918(4) Å, b = 12.0928(6) Å and c = 12.6759(7) Å and Z = 4. The structure has been characterized by FT-IR, NMR (¹H and ¹³C) and X-ray diffraction methods. There exists two C—H⋯O intermolecular hydrogen bond and two π…π interactions. Density functional theory (DFT/B3LYP/6-311 + + G(d, p)) has been employed for the optimization of the structure and the same was compared with the X-ray structure. The HOMO-LUMO energy gap and molecular electrostatic potential maps have been computed. The energy gap of 4.06 eV indicates that the molecule is stable and less reactive. Besides this, the molecular electrostatic potential (MEP) help determine the reactive sites of the molecule. The Hirshfeld surface analysis and 2-D fingerprint plots help explore the nature and percentage contribution of intermolecular interactions. The highest contribution to the total Hirshfeld surface area is from H…H contacts (47.2%) while the contribution of O…H/H…O contacts is 26.4%. The strength and nature of interactions present in the molecule have been characterized by RDG-based NCI and QTAIM analysis. DOS analysis has been performed to investigate the contribution of various orbitals. The molecular docking analysis analysis was performed to determine the binding patterns of 3-MNB with 1CX2, revealing a binding energy of -7.3 Kcal/mol, suggesting its potential as a COX-2 inhibitor.