On the hyacinth macaw's nesting tree: density of young manduvis around adult trees under three different management conditions in the Pantanal wetland, Brazil.

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A tetranuclear diphenyltin(IV) complex and its catalytic activity in the aerobic Baeyer-Villiger oxidation of cyclohexanone

The synthesis and crystal structure of the new tetranuclear diphenyltin(IV) compound [{SnPh2}{SnPh2(OCOMe)}(μ2-OMe)(μ3-O)]2 (1), generated from the reaction of [SnPh2Cl2] and NaOCOMe, are described. Single crystal X-ray diffraction revealed that 1 is a tetranuclear complex with four diphenyltin(IV) units which are inter-connected by μ3-oxido and μ2-methoxido bridges leading to a ladder-like Sn4O4 cluster. Structural comparison with related compounds found in crystallographic data base (CSD) attests that such tetranuclear systems are more abundant than related oxido bridged dimers or trimers. Complex 1 efficiently catalyzes the aerobic Baeyer-Villiger oxidation of cyclohexanone to ε-caprolactone, under mild conditions. With the sacrificial benzaldehyde method, quantitative conversion was observed in just 30 min with a remarkable selectivity. © 2018 Elsevier B.V

A tetranuclear diphenyltin(IV) complex and its catalytic activity in the aerobic Baeyer-Villiger oxidation of cyclohexanone

The synthesis and crystal structure of the new tetranuclear diphenyltin(IV) compound [{SnPh2}{SnPh2(OCOMe)}(μ2-OMe)(μ3-O)]2 (1), generated from the reaction of [SnPh2Cl2] and NaOCOMe, are described. Single crystal X-ray diffraction revealed that 1 is a tetranuclear complex with four diphenyltin(IV) units which are inter-connected by μ3-oxido and μ2-methoxido bridges leading to a ladder-like Sn4O4 cluster. Structural comparison with related compounds found in crystallographic data base (CSD) attests that such tetranuclear systems are more abundant than related oxido bridged dimers or trimers. Complex 1 efficiently catalyzes the aerobic Baeyer-Villiger oxidation of cyclohexanone to ε-caprolactone, under mild conditions. With the sacrificial benzaldehyde method, quantitative conversion was observed in just 30 min with a remarkable selectivity. © 2018 Elsevier B.V

DNA and BSA binding and cytotoxic properties of copper(II) and iron(III) complexes with arylhydrazone of ethyl 2-cyanoacetate or formazan ligands

Several known water soluble [Cu(1κN,O2:2κO-HL1)(S)]2 [S = CH3OH (1), (CH3)2NCHO (2)] and [Cu(κN-HL1)(en)2]·CH3OH·H2O (3) CuII complexes were prepared by reaction of CuII nitrate hydrate with the new (E/Z)-4-(2-(1-cyano-2-ethoxy-2-oxoethylidene)hydrazinyl)-3-hydroxybenzoic acid (H3L1), in the presence (for 3) or absence (for 1 and 2) of ethylenediamine (en), while the FeIII complex [Fe(κN3-HL2)2] (4) was synthesized by treatment of iron(iii) chloride hexahydrate with the new (1E,1E)-N′,2-di(1H-1,2,4-triazol-3-yl)diazenecarbohydrazonoyl cyanide (H3L2). The interaction of calf thymus DNA (CT DNA) and bovine serum albumin (BSA protein) with complexes 1-4 has been investigated by absorption and fluorescence titration methods. The observed DNA binding constants, number of DNA binding sites (s ≤ 1) for the complexes and viscosity data suggest the intercalative mode of binding to CT DNA. All the complexes show good binding propensity to the BSA protein, giving KBSA values of 0.97(±0.10) × 106 (1), 1.19(±0.09) × 106 (2), 0.50(±0.01) × 106 (3) and 1.06(±0.08) × 106 M-1 (4). An in vitro anti-proliferative study establishes the anticancer potency of complexes 1-4 and cisplatin against the human cervical (HeLa) and breast (MCF7) cancer cell lines; noncancer breast epithelial (MCF10) cells were also investigated. The observed IC50 values of complexes 1 (8.3, 11.9 and 44.8 μM), 2 (7.0, 7.1 and 35.6 μM), 3 (18.1, 20.4 and 58.8 μM), 4 (13.2, 15.1 and 79.4 μM) and cisplatin (4.02, 3.42 and 89.5 μM) against the HeLa, MCF7 and MCF-10a cells, respectively, suggest that 2 can be explored further as a potential anticancer drug. © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2017

DNA and BSA binding and cytotoxic properties of copper(II) and iron(III) complexes with arylhydrazone of ethyl 2-cyanoacetate or formazan ligands

Several known water soluble [Cu(1κN,O2:2κO-HL1)(S)]2 [S = CH3OH (1), (CH3)2NCHO (2)] and [Cu(κN-HL1)(en)2]·CH3OH·H2O (3) CuII complexes were prepared by reaction of CuII nitrate hydrate with the new (E/Z)-4-(2-(1-cyano-2-ethoxy-2-oxoethylidene)hydrazinyl)-3-hydroxybenzoic acid (H3L1), in the presence (for 3) or absence (for 1 and 2) of ethylenediamine (en), while the FeIII complex [Fe(κN3-HL2)2] (4) was synthesized by treatment of iron(iii) chloride hexahydrate with the new (1E,1E)-N′,2-di(1H-1,2,4-triazol-3-yl)diazenecarbohydrazonoyl cyanide (H3L2). The interaction of calf thymus DNA (CT DNA) and bovine serum albumin (BSA protein) with complexes 1-4 has been investigated by absorption and fluorescence titration methods. The observed DNA binding constants, number of DNA binding sites (s ≤ 1) for the complexes and viscosity data suggest the intercalative mode of binding to CT DNA. All the complexes show good binding propensity to the BSA protein, giving KBSA values of 0.97(±0.10) × 106 (1), 1.19(±0.09) × 106 (2), 0.50(±0.01) × 106 (3) and 1.06(±0.08) × 106 M-1 (4). An in vitro anti-proliferative study establishes the anticancer potency of complexes 1-4 and cisplatin against the human cervical (HeLa) and breast (MCF7) cancer cell lines; noncancer breast epithelial (MCF10) cells were also investigated. The observed IC50 values of complexes 1 (8.3, 11.9 and 44.8 μM), 2 (7.0, 7.1 and 35.6 μM), 3 (18.1, 20.4 and 58.8 μM), 4 (13.2, 15.1 and 79.4 μM) and cisplatin (4.02, 3.42 and 89.5 μM) against the HeLa, MCF7 and MCF-10a cells, respectively, suggest that 2 can be explored further as a potential anticancer drug. © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique 2017