Mononuclear or Coordination Polymer Complexes? Both Are Possible for 3,6,9-Trioxaundecanedioic Acid.

Investigating the driving forces leading to the formation of a specific supramolecular architecture among a wide spectrum of all the possibly obtainable structures is not an easy task. The contemporary literature provides several models for correctly predicting the thermodynamically accessible structures that can originate from a library of building blocks. Definitions are rigid by their very nature, so their application may sometimes require a shift in perspective.

Intermolecular Forces Driving Hexamethylenetetramine Co-Crystal Formation, a DFT and XRD Analysis.

Interest in co-crystals formation has been constantly growing since their discovery, almost a century ago. Such success is due to the ability to tune the physical-chemical properties of the components in solid state by avoiding a change in their molecular structure. The properties influenced by the co-crystals formation range from an improvement of mechanical features and chemical stability to different solubility.

Do Secondary Electrostatic Interactions Influence Multiple Dihydrogen Bonds? AA-DD Array on an Amine-Borane Aza-Coronand: Theoretical Studies and Synthesis.

Hydrogen bond plays a key role in a wide range of inorganic, organic, as well as biological systems. The understanding on how the chemical environment can affect this kind of interaction is crucial to predict its binding strength and consequently the robustness and the dynamic properties of many supramolecular systems. In this paper a new donor-acceptor complex was synthesized and characterized by SCXRD, showing for the first time in an organic system an AA-DD pattern of a particular hydrogen interaction, called dihydrogen bond.

Long-Term Results of Aortic Root Surgery in Marfan Syndrome Patients: A Single-Center Experience.

Background And Aim Of The Study: The study aim was to compare long-term results of Marfan syndrome (MFS) patients affected by aortic root disease undergoing aortic root replacement with the Bentall or David operation.

Methods: Since 1994, a total of 59 patients has been followed at the authors' Marfan Center, having undergone either a Bentall operation (Bentall group, n = 30) or a David operation (David group, n = 29).

Results: No operative mortality was recorded.

Identification of 2-thioxoimidazolidin-4-one derivatives as novel noncovalent proteasome and immunoproteasome inhibitors.

This paper describes the design, synthesis, and biological evaluation of 2-thioxoimidazolidin-4-one derivatives as inhibitors of proteasome and immunoproteasome, potential targets for the treatment of hematological malignancies. In particular, we focused our efforts on the design of noncovalent inhibitors, which might be a promising therapeutic option potentially devoid of drawbacks and side-effects related to irreversible inhibition. Among all the synthesized compounds, we identified a panel of active inhibitors with K values towards one or two chymotrypsin-like activities of proteasome (β5c) and immunoproteasome (β5i and β1i subunits) in the low micromolar range.

Synthesis of spiro[isoindole-1,5'-isoxazolidin]-3(2)-ones as potential inhibitors of the MDM2-p53 interaction.

A series of spiro[isoindole-1,5-isoxazolidin]-3(2)-ones has been synthesized by 1,3-dipolar cycloaddition of -benzylnitrone with isoindolin-3-methylene-1-ones. The regio- and stereoselectivity of the process have been rationalized by computational methods. The obtained compounds show cytotoxic properties and antiproliferative activity in the range of 9-22 μM.

Halogen and Hydrogen Bonding Benzothiophene Diol Derivatives: A Study Using ab initio Calculations and X-Ray Crystal Structure Measurements.

The aim of this study is to describe and compare the supramolecular interactions, in the solid state, of chloro-, bromo-, and iodobenzothiophene diols. The compounds were obtained through organo-catalyzed reactions starting from 3-substituted halobenzothiophene carbaldehydes. Energies of the noncovalent interactions were obtained by density functional theory calculations.

Crystal structure of N,N'-bis-(4-methyl-phen-yl)di-thio-oxamide.

Two half mol-ecules of the title compound, C16H16N2S2, are present in the asymmetric unit and both mol-ecules are completed by crystallographic inversion centers at the mid-points of the central C-C bonds: the lengths of these bonds [1.538 (5) and 1.533 (5) Å] indicate negligible electronic delocalization.

Crystallographic study and biological evaluation of 1,4-dimethyl-N-alkylcarbazoles.

The 9-(bromoalkyl)-1,4-dimethyl-9H-carbazole (2a-d) derivatives, characterized by the presence of five or seven methylenic spacer groups bonded to the carbazole nitrogen, have been synthesized from the corresponding 1,4- dimethyl-9H-carbazole and appropriate dibromoalkane following a general synthetic method. All the prepared species have been fully characterized by means of IR, and (1)H and (13)C NMR spectroscopy, GC-MS and Elemental analysis. Good crystals of the 2c have been obtained and the crystal structure has been solved by means of X-ray diffractometry.

Poly[(μ4-decanedio-ato)cobalt(II)].

In the title compound, [Co(C10H16O4)] n , the Co(II) atom is bonded in a slightly distorted tetra-hedral environment by four O atoms from the bridging sebacate dications, comprising two separate half-ligands which lie across crystallographic inversion centres. In the three-dimensional network coordination polymer, there are two different spatial extensions of Co(II) atoms, one with the Co(II) atoms lying parallel to (100) [Co⋯Co = 4.653 (1) Å], the other lying parallel to (010) [Co⋯Co = 4.

{2,6-Bis[(pyridin-2-yl)sulfanylmeth-yl]pyridine-κ(2) N,N'}(η(3)-prop-2-en-yl)palladium(II) hexa-fluoro-phosphate.

The title compound, [Pd(C3H5)(C17H15N3S2)]PF6, is built up by a [(η(3)-all-yl)Pd](2+) fragment coordinated by a 2,6-bis-[(pyridin-2-yl)sulfanylmeth-yl]pyridine ligand coordinated through the N atoms. One of the S atoms is at a close distance to the metal centeratom [3.2930 (8) Å].

Synthesis, characterization, crystal structure, and biological studies of two new Cd (II) complexes with 4'-(4-chlorophenyl)-2,2' :6',2"-terpyridine (Clphtpy).

Two new Cd(II) complexes, with the ligand 4'-(4-chlorophenyl)-2,2':6',2"-terpyridine (Clphtpy) formulated as: [Cd(Clphtpy)(NO3)2H2O] (1), and [Cd(Clphtpy)(N3)2]2 (2), have been synthesized and characterized by CHN elemental analysis as well as FT-IR, 1H NMR, absorption and emission spectroscopy, thermal analysis and analyzed structurally by X-ray single-crystal diffraction. The single crystal X-ray analysis showed that the coordination number in complex 1 and 2 were seven and six with N3O4 and N6 coordination sphere, respectively. The antibacterial activities of the synthesized complexes were tested against four gram-positive and four gram-negative bacteria.

Tetra-kis(μ-4-chloro-benzoato-κ(2) O:O')bis-[(ethanol-κO)copper(II)](Cu-Cu).

In the centrosymmetric dinuclear title Cu(II) complex, [Cu2(C7H4ClO2)(C2H5OH)2], the Cu-Cu distance is 2.5905 (4) Å. The two metal atoms are bridged by four 4-chloro-benzoate ligands and each has an ethanol mol-ecule in the axial position of the overall octahedral coordination environment.

31-Benz-yloxy-5,11,17,23,29-penta-tert-butyl-calix[5]arene-32,33,34,35-tetra-ol.

The title compound, C62H76O5, known to be one of the most versatile synthetic precursors/inter-mediates of calix[5]arene derivatives, adopts an approximate Cs -symmetric cone-in conformation. The aryl-oxybenzyl ring is tilted in such a way that the p-tert-butyl group fills the macrocycle cavity, while the benzyl group moves away from the cavity axis. In the crystal, this conformational arrangement is secured by intra- and inter-molecular O-H⋯O hydrogen bonds forming inversion dimers.

5-Amino-3-methyl-1,2-oxazole-4-carbonitrile.

In the title compound, C(5)H(5)N(3)O, the isoxazole ring is essentially planar, with a maximum deviation of 0.007 (1) Å from the least-squares plane. The N atom of the amine group exhibits sp(2) character (sum of bond angles around this atom = 358°).

Dianilinium bis-(pyridine-2,6-dicarboxyl-ato-κ(3)O(2),N,O(6))cuprate(II) hexa-hydrate.

The asymmetric unit of the title complex, (C(6)H(8)N)(2)[Cu(C(7)H(3)NO(4))(2)]·6H(2)O, contains half a copper(II)-dipicolinate complex located on a twofold rotation axis, one protonated aniline mol-ecule and three solvent water mol-ecules. The Cu(II) atom is coordinated by four O atoms and two N atoms from two dipicolinate ligands in a distorted octa-hedral environment. In the crystal, the components are linked into a three-dimensional framework by inter-molecular O-H⋯O and N-H⋯O inter-actions.

[(Pyridine-2,6-dicarboxyl-ato)copper(II)]-μ-(pyridine-2,6-dicarboxyl-ato)-[bis-(ethyl-enediamine)-copper(II)]-μ-(pyridine-2,6-dicarboxyl-ato)-[(pyridine-2,6-dicarboxyl-ato)copper(II)] ethyl-enediamine monosolvate tetra-hydrate.

The title compound, [Cu(3)(C(7)H(3)NO(4))(4)(C(2)H(8)N(2))(2)]·C(2)H(8)N(2)·4H(2)O, was obtained by the reaction of copper(II) acetate dihydrate with pyridine-2,6-dicarb-oxy-lic acid (H(2)dipic) and ethyl-enediamine (en) in an aqueous solution. All of the Cu(II) atoms in the trinuclear centrosymmetric title complex are six-coordinated in a distorted octa-hedral geometry with N(2)O(4) and N(4)O(2) environments for the outer and central Cu(II) atoms, respectively. Various inter-actions, including numerous O-H⋯O and C-H⋯O hydrogen bonds and C-O⋯π stacking of the pyridine and carboxyl-ate groups [O⋯centroid distances = 3.

Allylpalladium dimers with metals connected by binucleating dithiooxamidates in two different coordination modes: solution behavior and solid-state structure.

A series of allylpalladium dimers having metals connected by binucleating dialkyldithiooxamidate [N(R)SC-CS(R)N](2-) [R = methyl, ethyl, isopropyl, benzyl, isoamyl, (S)-1-(1-phenyl)ethyl, meso-(1-phenyl)ethyl, and rac-(1-phenyl)ethyl] were prepared by reacting the monochelate [(η(3)-allyl)Pd(N(R)SC-CS(R)NH κ-S,S Pd)] with [(η(3)-allyl)PdCl](2) in chloroform. At low temperature (20 °C), the bimetallic complexes [(η(3)-allyl)Pd](2)(μ-dialkyldithiooxamidate κ-N,N' Pd, κ-S,S' Pd') (kinetic compounds) are formed in a short reaction time (10 min). At a higher temperature (50 °C) and a longer reaction time (24 h), the corresponding bimetallic isomers [(η(3)-allyl)Pd](2)(μ-dialkyldithiooxamidate κ-N,S Pd, κ-N',S' Pd') (thermodynamic compounds) are obtained.

(S)-2-[(2-Hy-droxy-benz-yl)aza-nium-yl]-4-(methyl-sulfan-yl)butano-ate.

The zwitterionic title compound, C(12)H(17)NO(3)S, is a reduced Schiff base derived from (S)-N-(2-hy-droxy-benzyl-idene)methio-nine. An intra-molecular inter-action between the N-H and carboxyl-ate groups forms a roughly planar (r.m.

3-[2-(1H-1,3-Benzodiazol-2-yl)eth-yl]-1,3-oxazolidin-2-one.

In the title compound, C(12)H(13)N(3)O(2), the dihedral angle between the oxazolone ring and the benzimidazole unit is 45.0 (5)°, exhibiting a staggered conformation at the Cα-Cβ bond. In the crystal, a strong N-H⋯N hydrogen bond links the mol-ecules into a C(4) chain along the c axis while a C-H⋯O hydrogen-bonding inter-action generates a C(5) chain along the a axis, i.

The absolute configuration of palladium(II) and ruthenium(II) pseudochiral centers in either chiral or achiral environments.

The meso-dithioxamide H-((R)-1-(1-phenyl)ethyl)-NSC-CSN-((S)-1-(1-phenyl)ethyl)-H (H(2)-mesoDTO) bonds [(η(6)-p-cymene)chlorido-ruthenium(II)](+) or [(η(3)-allyl)-palladium(II)](+) fragment and provides the C(s) symmetrical complexes [(η(6)-p-cymene)ClRu(H-mesoDTO κ-S,S Ru)] (1) and [(η(3)-allyl)palladium(H-mesoDTO κ-S,S Pd)] (2). These complexes are pseudochiral, and each of them exists as a mixture of two symmetrical meso forms. The improper symmetry of [(η(3)-allyl)palladium(H-mesoDTO κ-S,S Pd)] has been broken in two different ways: (i) by changing the symmetrical allyl moiety with a η(3)-crotyl frame or (ii) by substituting the residual amidic hydrogen in the dithiooxamidate ligand with a M(PR(3))Cl(+) fragment (M = Pd or Pt and PR(3) = triorganophosphine).

Dithioether ligands containing a 2,6-disubstituted pyridine linker with two thioether-heterocycle arms.

The structure of 2,6-bis(2-pyridyltsulfanylmethyl)pyridine (pytmp), (I), C(17)H(15)N(3)S(2), presents a twisted conformation, with the three planar moieties almost perpendicular to each other. The structures of two related derivatives, namely 2,6-bis(6-methyl-2-pyridylsulfanylmethyl)pyridine (mpytmp), (II), C(19)H(19)N(3)S(2), and 2,6-bis(4-methyl-2-pyrimidylsulfanylmethyl)pyridine (mprtmp) n-pentane hemisolvate, (III), C(17)H(17)N(5)S(2).0.

A functionalized enol lactone containing a protected α-amino acid.

The crystal structure of N-(3,9-dimethyl-4-phenyl-2,5-dioxo-3,4-dihydro-2H,5H-pyrano[3,2-c]chromen-3-yl)-N-methylbenzamide methanol monosolvate, C(28)H(23)NO(5)·CH(3)OH, has been determined at room temperature by X-ray diffraction. Structural parameters are discussed with reference to ab initio calculations.

catena-Poly[[[μ-aqua-penta-aqua-dizinc(II)]-μ(4)-benzene-1,2,4,5-tetra-carboxyl-ato] dihydrate].

The asymmetric unit of the title compound, {[Zn(2)(C(10)H(2)O(8))(H(2)O)(6)]·2H(2)O}(n), contains two distinct Zn atoms joined by a bridging water molecule and two bridging carboxyl-ate groups belonging to distinct halves of benzene-1,2,4,5-tetra-carboxyl-ate (tbec) tetra-anionic ligands, both lying on crystallographic inversion centres. The structure of this new isopolymorphic one-dimensional coordination polymer features asymmetric bimetallic octa-hedral knots. O-H⋯O hydrogen bonds between water molecules and carboxylate O atoms help to consolidate the crystal packing.

catena-Poly[bis-(4-amino-pyridinium) [[tetra-aqua-nickel(II)]-μ-benzene-1,2,4,5-tetra-carboxyl-ato] dihydrate].

The asymmetric unit of the title compound, {(C(5)H(7)N(2))(2)[Ni(C(10)H(2)O(8))(H(2)O)(4)]·2H(2)O}(n), contains an Ni(II) atom, two water mol-ecules of coordination, one half of a benzene-1,2,4,5-tetra-carboxyl-ate (btec) anionic ligand, one 4-amino-pyridinium cation (papy) and an uncoordinated water mol-ecule. The metal center lies on an inversion center and adopts an octa-hedral geometry with the carboxyl-ate groups tilted out of the mean plane formed by the btec. In the crystal, mol-ecules are linked into one-dimensional coordination polymers running along the ac diagonal.