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

A novel mixed ligand Cu(II) complex of 4,4,4-trifluoro-1-phenyl-1,3-butanedione and 8-hydroxyquinoline was synthesized and spectroscopically characterized. The phenolate oxygen bridged dinuclear (polymorph 1) and solvent-induced mononuclear (polymorph 2) forms were obtained using DMSO and acetic acid solvents. The solvato supramolecular isomeric forms (P1¯ and P21/a) of the complex are confirmed by the single crystal X-ray diffraction method. In polymorph 1, a hydrogen-bonded one-dimensional network is constructed by C–H⋯O contacts, whereas, in polymorph 2, a two-dimensional ladder-like architecture is formed by the interplay of C–H⋯O, C–H⋯F and F⋯F contacts. The vital role of distinct non-covalent interactions in the establishment of a unique structural topology is analysed by Hirshfeld surfaces, 2D fingerprint plots, QTAIM and the NCI index model. The anisotropies in the three-dimensional structural topology are visualized through their energy frameworks and evidenced by their interaction energies. The electronic structures of the polymorphs were optimized by density functional theory calculations to explore their coordination stability and chemically reactive parameters. Polymorph 1 exhibits potential antibacterial activity against methicillin-resistant Staphylococcus aureus with a minimum inhibitory concentration of 8 μg mL−1. Further, polymorphs were docked to penicillin-binding protein 2, where polymorph 1 had a binding score of −10.0 kcal mol−1, greatly supporting the in vitro results. [ABSTRACT FROM AUTHOR]

(E)-1-(4-(1-Isobutyl-1H-imidazo[4,5-c]quinolin-4-ylamino)phenyl)-3-phenylprop-2-en-1-one, C29H26N4O, was synthesized and characterized by spectroscopy and elemental analysis. The crystal structure was determined from single crystal X-ray diffraction data. It crystallizes in the triclinic crystal system with the space group Pī, and unit cell parameters, a = 9.667(2) Å, b = 11.408(3) Å, c = 12.286(3) Å,α= 116.7(1)°,β= 91.5(1)°,γ= 99.6(1)°, Z = 2, CuKα= 1.5418 Å, and finalR1 andwR2 being 0.067 and 0.189, respectively. The molecular and crystal structures of the title molecule are stabilized by intramolecular interactions, N—H···N, C—H···N, and C—H···O, and intermolecular interaction, C—H···O. [ABSTRACT FROM PUBLISHER]

The substituted imidazole C29H24N2O2was prepared via multicomponent reactions and the product crystallized using dimethylformamide. The structure of the compound was established by elemental analysis, FT-IR, thermogravimetric analysis, UV-Visible, and single-crystal X-ray diffraction. The molecule is crystallized in the tetragonal crystal system with the space group P43212 and with unit cell parametersa= 12.226(1) Å,b= 12.226(1) Å,c= 31.807(3) Å, andZ= 8. The molecular and crystal structure of the title molecule is stabilized by intramolecular interactions, O‒H···N and C‒H···N, and intermolecular interaction, C‒H···O. [ABSTRACT FROM AUTHOR]

The compound (Z)-2-(3-chlorophenyl)-N’-hydroxyacetamidine, (2) was synthesized and characterized by1H NMR, FT-IR, TGA, UV-Visible Spectra, and elemental analysis. Its molecular structure was solved by single-crystal X-ray diffraction method. The title molecule, C8H9ClN2O is crystallized in the monoclinic crystal system with the space group P21/c and with unit cell parameters a = 8.7092(4) Å, b = 8.2370(4) Å, c = 12.5256(6) Å,β= 102.252(3)°, and Z = 4. The molecular and crystal structure of the title molecule is stabilized by an intramolecular interaction of the type N—HċċċO, and the intermolecular interactions of types N—HċċċN and O—HċċċN. [ABSTRACT FROM AUTHOR]

The compound (Z)-2-N′-hydroxyisonicotinamidine, (2) was synthesized and characterized by1H NMR, FT-IR, FAB-Mass, UV-Visible Spectra, and elemental Analysis. Its molecular structure was solved by single crystal X-ray diffraction method. The title molecule, C6H7N3O is crystallized in the orthorhombic crystal system with the space group Pna21and with unit cell parameters a = 12.5664(8) Å, b = 8.8622(6) Å, c = 5.7953(4) Å, α = 90°, β = 90°, γ = 90°, and Z = 4. The molecular and crystal structure of the title molecule is stabilized by an intramolecular interaction of the type N—H···O, and the intermolecular interactions of types N—H···N and O—H···N. [ABSTRACT FROM PUBLISHER]

The article discusses the crystal structure of 2-phenoxyethyl 2-hydroxybenzoate, whose chemical formulae is C15H14O4. Topics discussed include its physical properties, chemical formula, chemical structure, and its atomic coordinates and displacement parameters. It is noted that phenoxyethyl benzoate is being used in the synthesis of oxazoles, imidazoles and benzoxazepines

Detailed structural and non-covalent interactions in thioxotriaza-spiroderivative (DZ2) are investigated by single crystal structure anslysis and computational approaches. Its results were compared with the previously reported spiroderivative (DZ1). The crystal structure analysis revealed various C-H…O, N-H…O, C-H…N and N-H…S hydrogen bonds involved in constructing several dimeric motifs to stabilize the crystal packing. The differences and similarities in the relative contribution of non-covalent interactions in DZ1 and DZ2 compounds are compared using the Hirshfeld surface analysis and 2D fingerprint plots. The binding energies of specific molecular pairs and homodimers have been obtained using molecule-molecule interaction energy calculation. The hierarchy and topology of pair-wise intermolecular interactions are visualized through energy frameworks. The nature and strength of intra and intermolecular interactions were characterized using non-covalent interaction index analysis and the quantum theory of atoms in molecule approach. Further, molecular docking of compounds (DZ1 and DZ2) with SARS-CoV-2 main protease for COVID-19 is performed. And the superposition of these ligands and inhibitor N3, which is docked into the binding pocket of 7BQY, is presented. The binding affinity of -6.7 kcal/mol is observed, attributed to hydrogen bonding and hydrophobic interactions between the ligand and the amino acid residues of the receptor., Competing Interests: There are no conflicts of interest., (© 2021 Elsevier B.V. All rights reserved.)

The ATP binding cassette (ABC) transporters, represent one of the largest superfamilies of primary transporters, which are very essential for various biological functions. The crystal structure of ATP-binding subunit of an ABC transporter from Geobacillus kaustophilus has been determined at 1.77 Å resolution. The crystal structure revealed that the protomer has two thick arms, (arm I and II), which resemble 'L' shape. The ATP-binding pocket is located close to the end of arm I. ATP molecule is docked into the active site of the protein. The dimeric crystal structure of ATP-binding subunit of ABC transporter from G. kaustophilus has been compared with the previously reported crystal structure of ATP-binding subunit of ABC transporter from Salmonella typhimurium., (Copyright © 2015 Elsevier Inc. All rights reserved.)

UDP-N-acetyl-d-mannosamine dehydrogenase (UDP-d-ManNAcDH) belongs to UDP-glucose/GDP-mannose dehydrogenase family and catalyzes Uridine-diphospho-N-acetyl-d-mannosamine (UDP-d-ManNAc) to Uridine-diphospho-N-acetyl-d-mannosaminuronic acid (UDP-d-ManNAcA) through twofold oxidation of NAD(+). In order to reveal the structural features of the Pyrococcus horikoshii UDP-d-ManNAcADH, we have determined the crystal structure of the product-bound enzyme by X-ray diffraction to resolution of 1.55Å. The protomer folds into three distinct domains; nucleotide binding domain (NBD), substrate binding domain (SBD) and oligomerization domain (OD, involved in the dimerization). The clear electron density of the UDP-d-ManNAcA is observed and the residues binding are identified for the first time. Crystal structures reveal a tight dimeric polymer chains with product-bound in all the structures. The catalytic residues Cys258 and Lys204 are conserved. The Cys258 acts as catalytic nucleophile and Lys204 as acid/base catalyst. The product is directly interacts with residues Arg211, Thr249, Arg244, Gly255, Arg289, Lys319 and Arg398. In addition, the structural parameters responsible for thermostability and oligomerization of the three dimensional structure are analyzed., (Copyright © 2014 Elsevier Inc. All rights reserved.)

In the L-Serine biosynthesis, D-3-phosphoglycerate dehydrogenase (PGDH) catalyzes the inter-conversion of D-3-phosphoglycerate to phosphohydroxypyruvate. PGDH belongs to 2-hydroxyacid dehydrogenases family. We have determined the crystal structures of PGDH from Sulfolobus tokodaii (StPGDH) and Pyrococcus horikoshii (PhPGDH) using X-ray diffraction to resolution of 1.77Å and 1.95Å, respectively. The PGDH protomer from both species exhibits identical structures, consisting of substrate binding domain and nucleotide binding domain. The residues and water molecules interacting with the NAD are identified. The catalytic triad residues Glu-His-Arg are highly conserved. The residues involved in the dimer interface and the structural features responsible for thermostability are evaluated. Overall, structures of PGDHs with two domains and histidine at the active site are categorized as type IIIH and such PGDHs structures having this type are reported for the first time., (Copyright © 2014 Elsevier Inc. All rights reserved.)

NADP(+) dependent isocitrate dehydrogenase (IDH) is an enzyme catalyzing oxidative decarboxylation of isocitrate into oxalosuccinate (intermediate) and finally the product α-ketoglutarate. The crystal structure of Thermus thermophilus isocitrate dehydrogenase (TtIDH) ternary complex with citrate and cofactor NADP(+) was determined using X-ray diffraction method to a resolution of 1.80 Å. The overall fold of this protein was resolved into large domain, small domain and a clasp domain. The monomeric structure reveals a novel terminal domain involved in dimerization, very unique and novel domain when compared to other IDH's. And, small domain and clasp domain showing significant differences when compared to other IDH's of the same sub-family. The structure of TtIDH reveals the absence of helix at the clasp domain, which is mainly involved in oligomerization in other IDH's. Also, helices/beta sheets are absent in the small domain, when compared to other IDH's of the same sub family. The overall TtIDH structure exhibits closed conformation with catalytic triad residues, Tyr144-Asp248-Lys191 are conserved. Oligomerization of the protein is quantized using interface area and subunit-subunit interactions between protomers. Overall, the TtIDH structure with novel terminal domain may be categorized as a first structure of subfamily of type IV., (Copyright © 2014 Elsevier Inc. All rights reserved.)

In the title compound, C14H12N2O5S, the dihedral angle between the aromatic rings is 86.29 (1)° and the conformation between the C=O bond of the amide group and the meta-NO2 group is syn. The C-S-N-C torsion angle is -65.87 (19)° and the mol-ecule has an L-shaped conformation. In the crystal, the mol-ecules are connected into inversion dimers through pairs of N-H⋯O hydrogen bonds and C-H⋯O inter-actions forming R 2 (2)(8) and R 2 (2)(14) loops, respectively. The dimers are connected by further C-H⋯O inter-actions, thereby forming (100) sheets.

In the title compound, C10H9NO3, the dihedral angle between the benzo-furan ring system (r.m.s. deviation for the non-H atoms = 0.009 Å) and the -C-C(O)-N- segment is 83.76 (1)°. In the crystal, mol-ecules are linked by N-H⋯O and O-H⋯O hydrogen bonds, generating (001) sheets, which feature C(4) and C(10) chains.

In the title compound, C23H15F3N2O2S, the thia-zole ring makes dihedral angles of 12.98 (13), 49.30 (11) and 49.83 (12)° with the pyridine ring, the meth-oxy-phenyl ring and the (tri-fluoro-meth-yl)phenyl ring, respectively. In the crystal, mol-ecules are connected via C-H⋯O hydrogen bonds, forming chains along [010]. There are also C-H⋯π and C-F⋯π inter-actions present, forming a three-dimensional structure.

In the title compound C18H26BrNO2S, the thia-zepine ring adopts a boat conformation. The dihedral angle between the mean planes through the benzene ring and the four C atoms making up the basal plane of the boat is 35.8 (2)°. In the crystal, inversion dimers linked by pairs of N-H⋯O hydrogen bonds generate R 2 (2)(8) loops.