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The triangulo-{Er3} complex [Er3Cl(o-van)3(OH)2(H2O)5]Cl3·nH2O (n = 9.4; H(o-van) = o-vanillin) (1) was generated by an in situ method. The isolated Er(iii) complex 1 was characterized by elemental analysis and molecular spectroscopy. The results of single crystal X-ray diffraction studies have shown that 1 is built up of trinuclear [Er3Cl(o-van)3(OH)2(H2O)5]3+ complex cations, chloride anions and water solvate molecules. Within the complex cation the three Er(iii) central atoms are placed at the apexes of a triangle which are bridged by three (o-van) ligands with additional chelating functions and two μ3-OH ligands. Additionally five aqua and one chlorido ligands complete the octa-coordination of the three Er(iii) atoms. AC susceptibility measurements reveal that the compound exhibits slow magnetic relaxation with two relaxation modes.

The triangulo-{Er3} complex [Er3Cl(o-van)3(OH)2(H2O)5]Cl3·nH2O (n = 9.4; H(o-van) = o-vanillin) (1) was generated by an in situ method.  相似文献   
994.
Breast Cancer Research and Treatment - Many patients seek breast reconstruction following mastectomy. Debate exists regarding the best reconstructive option. The authors evaluate outcomes comparing...  相似文献   
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The new cembrane diterpenes leptodienone A (2) and leptodienone B (3) and the known compounds lopholide, lophodiol B, lophodione, and lophotoxin (1) have been isolated from the gorgonian Leptogorgia laxa collected in the Gulf of California. The structures of the new metabolites have been established by spectroscopic techniques. The in vitro cytotoxicity of the new compounds has been tested against three human tumor cell lines.  相似文献   
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The agreement between theoretical and experimental vibrational circular dichroism curves of (4R,9R,10R)-(+)-african-1(5)-ene-2,6-dione (1) and (4R,9S,10R)-lippifoli-1(6)-en-5-one (2), isolated from the widely used plant Lippia integrifolia, allowed the determination of the conformation and absolute configuration of 1 and confirmed both structural features for 2. Molecular modeling of 1 and 2 was carried out by means of a systematic and a Monte Carlo search protocol followed by geometry optimization employing density functional theory calculations with the B3LYP/6-31G(d), B3LYP/DGDZVP, and/or B3PW91/DGDZVP2 functionals/basis sets. Validation of the minimum energy conformations for both tricyclic substances was achieved by comparison of the experimental and theoretical vicinal (1)H-(1)H NMR coupling constants obtained by DFT-GIAO calculations.  相似文献   
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AIM OF THE STUDY: This investigation evaluated the effect of a hydroethanolic extract of Baccharis trimera on pregnant Wistar rats, once the plant is well-known consumed in pregnancy and little is known on its potentially toxic effects on pregnant women. MATERIAL AND METHODS: Thirty-five female rats were distributed into three groups. Those in treatments 1 and 2 were given 8.4 mg/kg of the extract orally from gestational day (GD) 1 to 19 and from GD 6 to 15, respectively, whereas those in the control group received distilled water orally from GD 1 to 19. Body weights were recorded on GD 1, 6, 15, and 20. On GD 20 animals were anesthetized, blood samples were collected and maternal livers, kidneys, and spleens were weighed and processed for histological studies. RESULTS: No clinical signs of maternal toxicity and no changes in hematological parameters were observed. Urea levels and kidney weights differed significantly between animals receiving treatment 1 and controls. Histopathological alterations were found in kidneys and livers in both treatment groups. CONCLUSIONS: The hydroethanolic extract of Baccharis trimera administered to pregnant rats at 8.4 mg/kg was toxic to maternal kidney and liver cells, although such alterations are reversible once administration is discontinued.  相似文献   
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