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In this work are presented all the conditions of synthesis explored to obtain a new family of compound with formula [Ln(4-OHBBA)3(H2O)2] (Ln = La, Pr). Powder X ray diffraction was used to identify the different phases obtained in the synthetic study. FT-IR spectroscopy and TG analysis for La and Pr pure phases are also reported. Optical properties of optically active CPs materials, solid state photoluminescence properties of La, Pr, La-(5%Eu) and La-(5%Tb) compounds were explored. We report the absorption, excitation and emission spectrum of the 4'-hydroxi-4-biphenylcarboxylic acid and a comparative description of the radiative (and no-radiative) processes in solid state in Ln-(4-OHBBA) and Ln-BPDC compounds. Finally, a principal component analysis was conducted in order to take in account both signal contributions from the sensor (LCE at 384 nm and the europium emission at 610 nm) and for classifying the type of analytes used to test the sensing response of the materials.

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Main group element coordination polymers (MGE-CPs) are important compounds for the development of multifunctional materials. However, there has been a shortage of studies regarding their structural, optical, catalytic, mechanical, and antibacterial properties. This work presents an exhaustive study of a set of crystalline MGE-CPs obtained from bismuth and indium metals and iminodiacetate, 1,2,4,5-benzenetetracarboxylate, and 2,2'-bipyridine as building blocks. An in-depth topological analysis of the networks was carried out. Additionally, nanoindentation studies were performed on two representative low-dimensional compounds in order to find the relationships between their structural features and their intrinsic mechanical properties (hardness and elasticity). The solid-state photoluminescence (SSPL) properties were also studied in terms of excitation, emission, lifetimes values, and CIE chromaticites. Moreover, the heterogeneous catalytic activities of the compounds were evaluated with the cyanosilylation reaction using a set of carbonylic substrates under solvent-free conditions. Finally, the inhibitory effect of the Bi-CPs on the growth of microorganisms such as Escherichia coli, Salmonella enterica serovar Typhimurium, and Pseudomonas aeruginosa, which are associated with relevant infectious diseases, is reported.

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A dihydrate pseudopolymorph of bis(2,4-dihydroxyphenyl)methanone, C(13)H(10)O(5)·2H(2)O, (I), was obtained during polymorphism screening of hydroxybenzophenone derivatives. This structure, in which the molecule sits on a twofold axis, was compared with the known anhydrous form of (I) [Schlemper (1982). Acta Cryst. B38, 554-559]. The role of water in the crystal assembly was established on the basis of the known monohydrate pseudopolymorph of 3,4-dihydroxybenzophenone [Landre, Souza, Corrêa, Martins & Doriguetto (2010). Acta Cryst. C66, o463-o465].

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Mebendazole hydrochloride [(5-benzoyl-1H-benzimidazole-2-yl)-carbamic acid methyl ester hydrochloride, MBZ.HCl], a new stable salt of mebendazole (MBZ), has been synthesized and characterized. It can easily be obtained from recrystallization of forms A, B, or C of MBZ in diverse solvents with the addition of hydrochloric acid solution. Crystallographic data reveals that the particular conformation adopted by the carbamic group contributes to the stability of the network. The crystal packing is stabilized by the presence of three N-H...Cl intermolecular interactions that form chains along the b axis. The XRD analyses of the three crystalline habits found in the crystallization process (square-based pyramids, pseudohexagonal plates, and prismatic) show equivalent diffraction patterns. The vibrational behavior is consistent with crystal structure. The most important functional groups show shifts to lower or higher frequencies in relation to the MBZ polymorphs. The thermal study on MBZ.HCl indicates that the compound is stable up to 160 degrees C approximately. Decomposition occurs in four steps. In the first step the HCl group is eliminated, and after that the remaining MBZ polymorph A decomposes in three steps, as happens with polymorphs B and C. (

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A duplicated nitrotienyl derivative was obtained as a by-product from the synthesis of a proposed molecular hybrid of a nitrotienyl derivative and isoniazid with an expected dual antimycobacteria mechanism. The structure was shown to be the 5,5'-dinitro-2-(2,3-diaza-4-(2'-tienyl)buta-1,3-dienyl)tiophene by X-ray crystallography. The minimal inhibitory concentration (MIC) determination of this compound proved to be promising against Mycobacterium pathogenic strains such as M. avium and M. kansasii, although it had a high level of mutagenicity, as observed in mutagenic activity tests.

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The synthesis, characterization and comparative biological study of a series of antibacterial copper complexes with heterocyclic sulfonamides were reported. Two kinds of complexes were obtained with the stoichiometries [Cu(L)2] . H2O and [Cu(L)2(H2O)4] . nH2O. They were characterized by infrared and electronic spectroscopies and the crystal structure of [Cu(sulfisoxazole)2(H2O)4] . 2H2O was determined by single crystal X-ray diffraction. It crystallized in the C2/c with Z = 8 monoclinic space group C2/c with Z = 8. The Cu(II) is in a slightly tetragonal distorted octahedron formed by four oxygen atoms from water molecules and two nitrogen atoms from two isoxazole rings. The antimicrobial activity was evaluated for all the synthesized complexes and ligands using the agar dilution test. The results showed that the complexes with five-membered heterocyclic rings were more active than the free sulfonamides while the pyrimidine, pyridine and pyridazine complexes had similar or less activity than the free ligands. In order to find an explanation for this behavior lipophilicity and superoxide dismutase-like activity were tested, showing that the [Cu(sulfamethoxazol)2(H2O)4] . 3H2O presented the highest antimicrobial potency and a superoxide dismutase-like activity comparable with pharmacological active compounds.

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A series of organotin(IV) derivatives were obtained employing 2,6-pyridinedicarboxylate as ligand: [{SnBu3(OOC)2C5H3N}n] (1), [SnBuCl(OOC)2C5H3N] (2) and [Sn(CHCH2)2(OOC)2C5H3N] (3). They were fully characterised by multinuclear NMR [1H, 13C{1H}, and 119Sn{1H}], IR spectroscopies and elemental analysis. In addition suitable crystals of (3) have shown a dimmeric arrangement by X-ray crystallographic studies, held together by Sn-O intermolecular interactions which persists in solution. The crystal packing shows hydrogen bonds joining the dimmers, forming two infinite one-dimensional chain. Each monomer comprises a Sn(IV) centre bonded to a pyridinecarboxylate-containing ring, through both nitrogen and oxygen donor atoms. It is also co-ordinated by a water molecule and two vinyl groups.

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Several natural compounds have been identified for the treatment of leishmaniasis. Among them are some alkaloids, chalcones, lactones, tetralones, and saponins. The new compound reported here, 7-geranyloxycoumarin, called aurapten, belongs to the chemical class of the coumarins and has a molecular weight of 298.37. The compund was extracted from the Rutaceae species Esenbeckia febrifuga and was purified from a hexane extract starting from 407.7 g of dried leaves and followed by four silica gel chromatographic fractionation steps using different solvents as the mobile phase. The resulting compound (47 mg) of shows significant growth inhibition with an LD50 of 30 æM against the tropical parasite Leishmania major, which causes severe clinical manifestations in humans and is endemic in the tropical and subtropical regions. In the present study, we investigated the atomic structure of aurapten in order to determine the existence of common structural motifs that might be related to other coumarins and potentially to other identified inhibitors of Leishmania growth and viability. This compound has a comparable inhibitory activity of other isolated molecules. The aurapten is a planar molecule constituted of an aromatic system with electron delocalization. A hydrophobic side chain consisting of ten carbon atoms with two double bonds and negative density has been identified and may be relevant for further compound synthesis.

Assuntos

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Several natural compounds have been identified for the treatment of leishmaniasis. Among them are some alkaloids, chalcones, lactones, tetralones, and saponins. The new compound reported here, 7-geranyloxycoumarin, called aurapten, belongs to the chemical class of the coumarins and has a molecular weight of 298.37. The compound was extracted from the Rutaceae species Esenbeckia febrifuga and was purified from a hexane extract starting from 407.7 g of dried leaves and followed by four silica gel chromatographic fractionation steps using different solvents as the mobile phase. The resulting compound (47 mg) of shows significant growth inhibition with an LD50 of 30 microM against the tropical parasite Leishmania major, which causes severe clinical manifestations in humans and is endemic in the tropical and subtropical regions. In the present study, we investigated the atomic structure of aurapten in order to determine the existence of common structural motifs that might be related to other coumarins and potentially to other identified inhibitors of Leishmania growth and viability. This compound has a comparable inhibitory activity of other isolated molecules. The aurapten is a planar molecule constituted of an aromatic system with electron delocalization. A hydrophobic side chain consisting of ten carbon atoms with two double bonds and negative density has been identified and may be relevant for further compound synthesis.

Assuntos

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Raman scattering and x-ray diffration were used to characterize the structural and vibrational properties of the Cs2NaGaxSc(1-x)F6 solid solutions, for x ranging from 0.0 to 1.0. The Raman spectra, taken at room and low temperature, allow us to follow the phase evolution in detail and indicate the breaking of the local symmetry since low Ga concentration levels. Five compositions were studied by x-ray diffraction: x = 0.0, 0.2, 0.5, 0.8, and 1.0. A cubic space group, Fm3m, was found to x = 0.0 and x = 0.2 and a trigonal one was found to x = 0.5, 0.8, and 1.0. Details of both phases are presented and the correlation between x-ray diffraction and Raman scattering is discussed.

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The reaction of [Ru(eta-Cp)(dppf)N(3)] (1) with equimolar amount of SnBr(2) yielded an interesting heterotrimetallic compound [Ru(eta-Cp)(dppf)SnBr(3)] (2) (dppf: 1,1'-bis-diphenylphosphinoferrocene). Compounds 1 and 2 were characterised by IR, NMR (1H, 13C, 31P and 119Sn), and 2, additionally, by 57Fe and 119Sn Mössbauer spectroscopy and X-ray crystallography. The latter results were as follows: monoclinic, C2/c, a = 32.8879(4)A, b = 11.9888(2)A, c = 20.8986(3)A, beta = 92.545(1)degrees, V = 8231.9(2)A(3), Z =8.

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The syntheses of nitrosyl-dimethylsulfoxide-ruthenium(II) complexes with general formula mer-[RuCl(3)(L)(DMSO)(NO)] (L=DMSO or CD(3)CN) is reported. The mer-[RuCl(3)(DMSO)(2)(NO)] (1) complex was obtained from the reaction of [RuCl(3)(NO)] with the sulfoxide ligand in acetone. The mer-[RuCl(3)(CD(3)CN)(DMSO)(NO)] (2) compound was obtained from mer-[RuCl(3)(DMSO)(2)(NO)] maintained in deuterated acetonitrile. These data suggest a slow kinetic reaction due the low lability of the DMSO ligand coordinated to the [Ru(II)-NO(+)] species. The crystal and molecular structures of (1) and (2) have been determined from X-ray studies. Crystal data: for (1), monoclinic, P2(1)/c, a=8.8340(2) A, b=12.0230(3) A, c=13.7064(4) A, beta=114.546(2) degrees, Z=4, R1=0.0429; for (2), monoclinic, P21/n, a=10.0180(7) A, b=9.5070(7) A, c=13.3340(9) A, beta=102.264(4) degrees, Z=4, R1=0.0472. The spectroscopic characterization of (1), in solid state (infrared spectrum) and in solution (nuclear magnetic resonance and cyclic voltammetry) is also described.

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We observe for the first time a structural phase transition in the oxyborate Fe3O2BO3 which occurs along three leg ladders present in this material. X-ray diffraction shows that this transition at 283 K is associated with a new phase where atomic displacements occur in alternate directions perpendicular to the axis and within the plane of the ladders. Magnetic data show that these displacements lead to the formation of singlet pairs which dissociate close to the structural transition. Anomalies in the transport properties also occur close to 283 K showing that the structural transition is related to a charge ordering phenomenon in a low dimensional structure.

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The title compound, raloxifene hydrochloride, C(28)H(28)NO(4)S(+).-Cl(-), belongs to the benzothiophene class of antiosteoporotic drugs. In the molecular cation, the 2-phenol ring sustains a dihedral angle of 45.3 (1) degrees relative to the benzo[b]thiophene system. The benzo[b]thiophene and phenyl ring planes are twisted with respect to the carbonyl plane, with the smallest twist component occurring between the phenyl and carbonyl planes. The N atom bears the positive charge in the molecular cation and the piperidine ring adopts an almost perfect chair conformation. The Cl(-) anion is involved in the formation of N-H...Cl and O-H...Cl intermolecular hydrogen bonds, which lead to the formation of a layer of molecular cations.

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The natural compound 5,10-dihydroxy-2,2-dimethylpyrano[3,2-b]xanthen-6(2H)-one (6-deoxyjacareubin), C(18)H(14)O(5), was isolated from leaves of Vismia latifolia (Guttiferae family). The compound has four six-membered rings. The molecule has two planar benzenoid and one planar pyranoid ring, plus a pyranoid ring in a distorted chair conformation. The crystal is stabilized by one intra- and one intermolecular hydrogen bond.

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An appreciable degree of pyramidalization of the amine N atom is observed in the title compound. The existence of polar chains, induced by N-H.O synthons, is confirmed. C-H.O interactions, not noted in a previous X-ray study, were found to stabilize further the known head-to-tail assembling of the chains. The structure can be described as non-polar (101) layers, embodying chains interlinked by centrosymmetric dimers, connected by C(aryl)-H.pi interactions. The latter are not present in m-nitroaniline, 2-methyl-4-nitroaniline and other related compounds with chains built from similar N-H.O synthons and assembled head-to-head. This finding implies that an obvious relationship between molecular recognition patterns and crystal structures should not be assumed.