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4-Aminodiphenylamino derivatives were investigated for their antioxidant and hydrophobicity character, together with other biological measurements, such as antimicrobial and antibiofilm activity. Among these nine compounds used, we obtained novel derivatives via reaction of the starting material with NBD-chloride. Therefore, we performed a full structural analysis for these compounds, i.e., elemental analysis, IR, UV-Vis, 1H- and 13C-NMR, ESI-MS, X-ray diffraction on single crystal, etc. The hydrophobicity of all the compounds was measured either experimentally using the RP-TLC technique, or via calculation using the fragments method. The other structural characteristics were analyzed, and a correlation between the experimental and computed properties was found. Moreover, the results of the biological evaluation showed that some of the synthesized compounds have antimicrobial and antibiofilm activity.

A series of nitrogen-containing organic molecules (4,4’-bipyridyl, trans-1,2-bis(4-pyridyl)ethylene, 1,2-bis(4-pyridyl)ethane, 4-aminopyridine and trans-1,4-diaminocyclohexane) was envisaged for cocrystallization experiments together with fluorescein. These compounds, containing pyridyl or/and amino nitrogen atoms, can act either as hydrogen bond acceptors for the phenol groups of fluorescein-generating cocrystals or as proton acceptors forming organic salts. Five cocrystals were obtained with the partners containing only pyridyl groups: {(H2Fl)2(bipy)} (1), {(H2Fl)2(bipy)(MeOH)2} (2), {(H2Fl)2(bpete)(EtOH)2} (3), {(H2Fl)(bpete)} (4), {(H2Fl)(bpeta)} (5). The compounds bearing amino groups deprotonate fluorescein producing salts: [(HFl)(Hampy)]∙2H2O (6), [(HFl)(Hampy)] (7), [(Fl)(H2diach)]∙3H2O (8), [(HFl)2(H2diach)]∙2H2O∙EtOH (9), and [(HFl)2(Fl)2(H2diach)3]∙4H2O (10). Optical properties of the cocrystals and salts were investigated.

Angioedema with life-threatening site is one of the most impressive and serious reasons for presenting to the ENT doctor. Among different causes (tumors, local infections, allergy reactions), an important cause is the side-effect of the angiotensin converting enzyme (ACE) inhibitors drugs. ACE-inhibitors-induced angioedema is described to be the most frequent form of bradykinin-mediated angioedema presented in emergency and also one of the most encountered drug-induced angioedema. The edema can involve one or more areas of the head and neck region, the most affected being the face, the lips, the tongue, followed by the larynx, when it may determine respiratory distress and even death. There are no specific diagnosis tests available and the positive diagnosis of ACE-inhibitors-induced angioedema is an exclusion diagnosis. The authors performed a review of the most important characteristics of the angioedema caused by ACE-inhibitors and present their experience emphasizing the diagnostic algorithm.

1-D coordination polymers, 1∞[Zn(fl)2]·2EtOH and 1∞[Zn(fl)2]·2MeOH, and a dinuclear complex, [{Zn(fl)2}2(dienpip)]·4H2O·4EtOH (dienpip = N,N′-bis(2-aminoethyl)piperazine), were obtained using Zn(II) ions and fluorescein anions (fl). Thermal analysis shows stability of the polymers after solvent removal up to more than 400 °C. Crystallization solvent molecules were removed under reduced pressure with the preservation of the polymeric structure, 1∞[Zn(fl)2]. Desolvated crystals were exposed to I2 vapors and the crystal structure determination by X-ray diffraction confirmed the presence of I2 molecules in the channels generated in crystals by the metal-organic framework. The iodine content, evaluated by X-ray diffraction, corresponds to the overall formula 1∞[Zn(fl)2]·0.3I2. The optical properties of the coordination polymers and the dinuclear complex have been investigated.

International audience; Five new cyanido-bridged heterometallic coordination polymers have been obtained by reacting PPh4[RuIII(salpn)(CN)2]·H2O (1) and AsPh4[RuIII(valen)(CN)2]·8.5H2O (2) (H2salpn and H2valen being Schiffbase proligands resulting from the condensation reaction of salicylaldehyde with 1,3-propanediamine and, respectively, o-vanillin with 1,2-ethanediamine) with divalent transition metal perchlorate salts: 1 1 [{RuIII(salpn)(CN)2}3{MII(DMF)3}2](ClO4)·4DMF (MII = Mn, 3; Co, 4) and 12 [{RuIII(valen)(CN)2}4{MII(DMF)3}2 {MII(DMF)4}](ClO4)2·4DMF (MII = Mn, 5; Co, 6; Ni, 7), respectively. The dicyanido species, trans-[Ru(salpn) (CN)2]− and trans-[Ru(valen)(CN)2]−, act as metalloligands with the 3d metal ions. Compounds 3 and 4 are isostructural one-dimensional (1D) coordination polymers with a ladder topology. Each MII ion is hexacoordinatedby three cyanido groups arising from three {Ru(salpn)(CN)2} units and by the oxygen atoms from three DMF molecules, which are coordinated at meridional positions. Compounds 5–7 are also isostructural, their structures consisting of 2D networks with a herringbone topology. The magnetic susceptibility measurements of these 1D and 2D systems reveal the presence of dominating RuIII–MII antiferromagnetic (AF) interactions in compounds 3, 4, 5 and 6, while ferromagnetic RuIII–NiII interactions are observed in 7. All these compounds stay in their paramagnetic state down to 1.8 K except compound 4 which possesses a 3D ordered AF ground state.

A series of novel derivatives of 3,5-dinitro-4-methoxyamino-benzoic acid were synthesized and fully characterized. Synthesis were performed by simple coupling reactions of the starting material with benzylamine, n-butylamine, 4-amino-antipyrine, benzocaine, 3,4-dimethyl-5-amino-isoxazole, 3,4-dimethoxyphenyl-2-ethylamine; besides, the corresponding methyl ester was also synthesized. The structural characterization of the new compounds was made by elemental analysis, IR, 1H and 13C NMR, UV–Vis, ESR, cyclic voltammetry, and single crystal X-ray diffraction (where appropriate). All compounds exhibits reversible acid-base behavior accompanied by colour change (yellow in acid media and blue at basic pH). Cyclic voltammetry showed an irreversible oxidation peak, however by chemical oxidation, these compounds generates persistent free radicals, evidenced also by ESR. Hydrophobicity and total antioxidant capacity of the compounds were also evaluated.

This work focuses on the investigation of the liquid crystalline behavior and luminescence properties of the lanthanide complexes of Eu(III), Sm(III) and Tb(III) with N-biphenyl-alkylated-4-pyridone ligands. The organic ligands having a biphenyl group attached via a long flexible spacer with either 9 or 10 carbon atoms were synthesized by the reaction between 4-hydroxypyridine and the corresponding bromide compounds. The chemical structures of the organic and lanthanide complexes were assigned based on elemental analysis, single-crystal X-ray diffraction, 1H, 13C NMR and IR spectroscopies, and thermogravimetric analysis (TGA). The X-ray diffraction analysis of a parent compound shows that the lanthanide ions are surrounded by three monodentate pyridone ligands and three bidentate nitrate ions, giving a 9-coordinate environment. The mesogenic behavior and the type of liquid crystalline phases exhibited by the new complexes were analyzed by differential scanning calorimetry (DSC) and polarizing optical microscopy (POM), and powder X-ray diffraction (XRD) studies. Only the lanthanide complexes with longer spacer (10) display a monotropic SmA phase, typically on a short thermal range (less than 10 °C). The complexes with shorter flexible chains (9) show no liquid crystalline properties with melting temperatures lower than their analogs with longer spacers. The emission spectra recorded in solid state at room temperatures show typical emission bands for each lanthanide ion employed (Eu(III), Tb(III) and Sm(III)).

Three new 1D cyanido-bridged 3d-4f coordination polymers, {[Gd(L)(H2O)2Fe(CN)6]·H2O}n(1GdFe), {[Dy(L)(H2O)2Fe(CN)6]·3H2O}n(2DyFe), and {[Dy(L)(H2O)2Co(CN)6]·H2O}n(3DyCo), were assembled following the building-block approach (L = pentadentatebis-semicarbazone ligand resulting from the condensation reaction between 2,6-diacetyl-pyridine and semicarbazide). The crystal structures consist of crenel-like LnIII-MIIIalternate chains, with the LnIIIions connected by the hexacyanido metalloligands through twociscyanido groups. The magnetic properties of the three complexes have been investigated. Field-induced slow relaxation of the magnetization was observed for compounds2DyFeand3DyCo. Compound3DyCois a new example of chain of Single Ion Magnets.&nbsp

International audience; A monodimensional heterotrimetallic coordination polymer of formula ∞ 1 [{Cu II Mn II L 2 } 3 {(µ-NC) 3 W V (CN) 5 } 2 ]·H 2 O (1) has been assembled from pre-designed [Cu II Mn II L 2 ] 2+ cationic modules and homoleptic [W V (CN) 8 ] 3-metalloligands (H 2 L 2 is the compartmental Schiff-base resulting from the stepwise condensation of 2,6-diformyl-p-cresol with ethylenediamine and di-Polynuclear complexes containing different paramagnetic metal ions are of high interest in molecule-based magnetism. [1] The large majority of the heterometallic molecular systems are constructed from two different metal ions. Conversely, complexes with three different paramagnetic centers are significantly less common, mainly because of the difficulties related to the scrambling of the metal ions. [2] A rational synthetic approach towards heterotrimetallic complexes consists of assembling preformed heterobimetallic modules and metalloli-gands. [2] Anionic cyanido complexes, homo-and heteroleptic, are excellent metalloligands for building magnetic molecule-based materials containing two, or more, different metal ions. [3] Our work in this field of research has been focused on the use of heterobimetallic tectons like phenoxido-bridged 3d-3d′ and 3d-4f complexes, with the metal ions enclosed into different coordination sites generated by dissymmetric macrocyclic or [a] Dr. 3111 ethylenetriamine). The magnetic properties of 1 have been investigated revealing a three-dimensional ordered antiferromag-netic ground state below 4 K resulting from different antiferro-magnetic interactions between all the spin carriers (S = 1/2 Cu II , S = 5/2 Mn II , and S = 1/2 W V centers). side-off compartmental ligands. [4] Indeed, most of the known heterotrimetallic complexes are assembled using 3d-4f precursors , which are easily obtained by exploiting the differences between 3d and 4f metal ions [coordination numbers, HSAB-"hard and soft (Lewis) acids and bases"-behavior] and using side-off compartmental ligands. [5] The synthesis of 3d-3d′ magnetic building-blocks is more delicate, since the differences mentioned above are less prominent. One appropriate pair is composed of Cu II and Mn II ions, especially because Mn II does not have a particular stereochemical preference, while Cu II does. Robust binuclear Cu II-Mn II complexes have been generated using side-off compartmental ligands (like H 2 L 1 see Scheme 1) with an open compartment that allows various coordination numbers and geometries for the Mn II ion, while the inner compartment hosts a Cu II metal ion with a square-planar or square-pyramidal geometry (Scheme 1). [6] Scheme 1. For analogous bis-phenoxido-bridged Cu II-Mn II binuclear complex, [Cu II Mn II L 2 ] 2+ (Scheme 1), the metal ions are held together by a dissymmetric compartmental Robson-type ligand. [7] Both binuclear systems are characterized by an S = 2 ground state, which results from a significant antiferromagnetic interaction between S = 1/2 Cu II and S = 5/2 Mn II centers, and are thus good building-block candidates for designing heterotrimetallic magnetic complexes and networks. For example, the self-as

Three Schiff base ligands derived from 2-aminofluorene and 3-methoxysalicylaldehyde (HL1), 3-ethoxysalicylaldehyde (HL2), or 2-formyl-6-hydroxymethyl-p-cresol (HL3) were synthesized and structurally characterized by X-ray diffraction on single crystals. The mononuclear complexes [Zn(L1)2] (4), [Zn(L2)2] (5), [Zn(L3)2]·CHCl3 (6a), and [Zn(L3)2] (6b) containing the monoanionic form of these ligands were obtained and structurally characterized. Luminescent properties of the ligands and complexes were investigated in solid-state.

We describe herein synthesis of novel hydroxy-bis-2,5-disubstituted-1,3,4-oxadiazoles and their ability to emit green light, through ESIPT mechanism. Unlike previous reports, our compounds exhibit very good quantum yields, most likely avoiding the presumed intramolecular fluorescence quenching in presence of the second oxadiazole moiety. Studies regarding behaviour of the compounds in polar and non-polar solvents are also described, indicating the possibility to modulate the emission according to the environment. The solid-state structural analysis, corroborated with fluorescence data, suggest the importance of the tert-butyl group in preservation of the luminescent properties. The corresponding benzyl-protected compounds, precursors to the target hydroxy-bis-2,5-disubstituted-1,3,4-oxadiazoles were also investigated for their optical properties and found to display very intense blue emission, with quantum yields values in dichloromethane (between 0.423 and 0.499) almost equal to the standard quinine sulfate.

A binuclear complex, [Ni2L2(NO3)(H2O)(CH3CN)]ClO4·CH3CN (1), has been obtained using a Schiff-base ligand (HL) derived from o-vanillin and 4-(2-aminoethyl)morpholine. The crystal structure of 1 has been solved. Both Ni(II) ions are hexacoordinated, but they display different coordination spheres. The exchange interaction between the two nickel ions is antiferromagnetic (J = −7.9 ± 0.2 cm−1; H = −JS1S2), in line with the DFT calculations. Compound 1 has been tested as a catalyst in the epoxidation of various olefins. The reaction of the same ligand with a mixture of cobalt(II) perchlorate and nitrate affords a mononuclear Co(III) complex, [CoL2(H2O)]ClO4·CH3OH (2).

Two new alkoxido-bridged heterometallic complexes of formula [CoIICoIII 3CuII 3(dea)6(CH3COO)3](ClO4)0.75(CH3COO)1.25 (1) and [CoII 2CoIII 2ZnII 3(tea)2(piv)6(CH3O)2(OH)2(CH3OH)2]·H2O 2 (H2dea=diethanolamine, H3tea=triethanolamine and Hpiv=pivalic acid) have been assembled using aminoalcohol ligands. The cationic core in 1 possesses a threefold crystallographic axis, and it exhibits a set of three copper(II), one cobalt(II) and three cobalt(III) ions arranged as a hexagon of alternating copper(II) and cobalt(III) ions around the central cobalt(II) ion. Each edge of the hexagon is defined by a double alkoxido bridge, the outer one being bis-monodentate with copper(II)-cobalt(III) pair whereas the inner one adopts a tris-monodentate coordination mode linking the Cu(II)-Co(III) pair with the central cobalt(II) ion. The acetate groups act as bidentate ligands towards the copper(II) ions. The intramolecular cobalt(II)-copper(II) separation is 3.157Å. A hexagon of two cobalt(II), two cobalt(II) and two zinc(II) ions distributed along three types of edges with a central zinc(II) ion occurs in 2. A tris-modentate alkoxido bridge is involved in all edges together with another bis-monodentate alkoxido bridge (CoIII-CoII and CoII-ZnII pairs) and a carboxylate-pivalate bridge in the syn-syn conformation. The five coordination at each peripheral zinc(II) ion is completed by a monodentate carboxylate-pivalate ligand whereas a methoxo group allows to achieve the six-coordination at each cobalt(III) ion. The intramolecular cobalt(II)-cobalt(II) separation through the inner zinc(II) ion is 6.309Å. The magnetic properties of 1 and 2 have been investigated in the temperature range 1.9-300K. The exchange interaction between the six-coordinate cobalt(II) and copper(II) ions through the double alkoxido bridges in 1 and that between the six-coordinate cobalt(II) ions across the diamagnetic zinc(II) ion in 2 are found to be ferromagnetic [J =+5.39(5) (1) and +1.05(2)cm-1 (2)], the accidental orthogonality between the interacting magnetic orbitals accounting for this behaviour in the two cases.

By reacting [MII(valpn)] or [MII(valdmpn)] mononuclear complexes with 4-aminopyridine in different molar ratios, five [MII(valXpn)(4-NH2-py)] and one [NiII(valdmpn)(4-NH2-py)2] complexes were obtained and structurally characterized (MII = NiII, CuII, ZnII; valpnH2 and valdmpnH2 are the Schiff bases resulted from the condensation of o-vanillin with 1,3-propylenediamine and 2,2-dimethyl-1,3-propylenediamine respectively). In the [Cu(valpn)(4-NH2-py)], [Ni(valpn)(4-NH2-py)], [Zn(valpn)(4-NH2-py)] and [Ni(valdmpn)(4-NH2-py)] complexes the metal ions are pentacoordinated with a square pyramidal geometry. The specific hydrogen bond interactions of the amino group belonging to the 4-aminopyridine with the free O2O′2 compartment of the Schiff base ligands led to various supramolecular architectures: rectangles, chains, and ladders. The spectroscopic properties of the compounds were also investigated.

The supramolecular interactions between 1,3-bis(4-pyridyl)azulene (azbbpy) as a hydrogen bond acceptor and a variety of aromatic hydrogen-bond donors produced new binary molecular co-crystals and a salt. All crystal structures display extensive and very complex hydrogen bond networks containing both homo- and heterosynthons formed through robust O–H⋯N and OH⋯O hydrogen bonds. The binary co-crystals of azbbpy with 4,4′-biphenol and 4,4′-oxo-bis-benzoic acid in a 1 : 1 ratio revealed that the recognition process differs. While 4,4′-biphenol acts both as a donor and an acceptor of protons, generating a two-dimensional supramolecular network in which azbbpy interacts with only one pyridine moiety, the co-crystallization with 4,4′-oxo-bis-benzoic acid yielded zig-zag chains formed by alternating acid–pyridine supramolecular heterosynthons. Co-crystallization with isophthalic acid yields a 2 : 1 system, 4, as hydrogen-bonded zig-zag supramolecular chains containing a R44(36) graph set organized through strong OH⋯N and weak C–H⋯N hydrogen bonds. Co-crystallization of azbbpy with trimesic acid in different ratios yielded two distinct systems: co-crystal 5 and salt 6. In 5, the trimesic acid molecules are assembled in supramolecular helical chains which are further connected by azbbpy through hydrogen bonding and π–π interactions into a 3D architecture with channels that host water molecules. A complicated supramolecular 3D architecture is also established between trimesic anions and azbbpyH+ cations in crystal 6, resulting in channels filled with disordered solvent molecules. These types of interactions were also evidenced in a quantitative way and confirmed on grounds of the Hirshfeld surface mapped with geometrical parameters that characterize close contacts in co-crystals. The optical properties of these supramolecular systems showed strong absorption bands in the visible region due to the azulene fragment.