Solubility of the Schiff Base Ligand and the Organoaluminum Supported by the Ligand in Pure Solvents: Characterization, Determination, Analysis, and Model Correlation

Schiff bases and organoaluminum compounds have wide applications in medicine and catalysis. TG-DSC provided melting points and melting enthalpies for the Schiff base ligand (1, 2-[[(2,6-difluorophenyl)­imino]­methyl]­phenol, CAS: 26672-04-8), with Tm at 349.55 K and ΔHfus at 22.797 kJ/mol, and for the organoaluminum compound supported by the ligand (2, [2-[[(2,6-difluorophenyl)­imino]­methyl]­phenoxy]­dimethylaluminum, CAS: 2851050-89-8), with Tm at 396.04 K and ΔHfus at 11.137 kJ/mol. The range of molecular electrostatic potentials for the two compounds was obtained by molecular electrostatic potential analysis, with the potential range for compound 1 being from +95.1 kJ/mol to −133.2 kJ/mol and that for compound 2 being from +139.9 kJ/mol to −132.7 kJ/mol. Hirshfeld surface analysis indicated that H···H contacts were the dominant contact interactions in these two molecules. In addition, the solubilities of the two compounds in 11 pure solvents were determined, and experimental data were correlated using 7 thermodynamic equations. The results displayed that the NRTL model had the best correlation result for the two compounds. These experimental results will have significant implications for the purification, crystallization, and industrial applications of similar types of substances

Change in heart rates of rats 2 hr after administration of VB.

<p>After being administered equivalent volumes of distilled water, rats in the NC group did not exhibit any changes in heart rate. After being administered VB, rats in groups LT-2, MT-2, and HT-2 exhibited significant decreases in heart rate (<i>p</i><0.01).</p

OPLS-DA analysis of liver extracts ¹H NMR data of LT-12, LT-6, LT-2, MT-2 and HT-2 groups in couple with NC group: score plots (a, c, e, g and i) and loading plots (b, d, f, h and j).

<p>In score plots, ellipses around sample points stood for the 90% confidence. Metabolite variation was visualized by the loading plots, which are color-coded according to the absolute value of the correlation coefficient; a reddish signal indicates a more significant contribution to the class separation than a bluish signal. Metabolites: 1, Leu/Ile; 2, Valine; 3, 3-HB; 4, Lactate; 5, Alanine; 6, Succinate; 7, GSH; 8, Choline; 9, Betaine; 10, Glycine; 11, Glycerol; 12, Glucose; 13, Uridine; 14, Inosine.</p

Score plots for OPLS-DA analysis of ¹H NMR data for serum, myocardial extracts and liver extracts of NC and VB treated groups.

<p>Two independent analyses were performed to study the time (NC, LT-2, LT-6 and LT-12) (a, b and c) and dose (NC, LT-2, MT-2 and HT-2) (d, e and f) effects of VB-induced toxicity. (a, d): score plots for serum; (b, e): score plots for myocardial extracts; (c, f): score plots for liver extracts. Ellipses around sample points stood for the 75% confidence.</p

Representative electrocardiogram tracings 2 hr after administration of VB.

<p>(a) NC group, (b) LT-2, (c) MT-2, (d) HT-2. After being administered VB, rats in groups LT-2, MT-2, and HT-2 exhibited marked disturbances in their ECG pattern (e.g., ST-segment elevation and pathological Q waves).</p

Schematic diagram of the metabolic pathways disturbed by VB.

<p>Metabolites in red and blue denoted the increase and decrease in their levels; those in black were not detected but are relevant.</p

Typical 500 MHz ¹H NMR spectra of serum samples (a), myocardial extract samples (b) and liver extract samples (c) obtained from all groups.

<p>Metabolites were respectively listed in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0119515#pone.0119515.s007" target="_blank">S1</a>–<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0119515#pone.0119515.s009" target="_blank">S3</a> Tables along with their chemical shifts.</p

Fold change plots color-coded with <i>p</i>-values adjusted by Benjamini-Hochberg method.

<p>Fold change plots indicating significance of altered metabolites in serum (a-e), myocardial extracts (f-j) and liver extracts (k-o) of NC rats vs. LT-12 rats (a, f and k), NC rats vs. LT-6 rats (b, g and l), NC rats vs. LT-2 rats (c, h and m), NC rats vs. MT-2 rats (d, i and n) and NC rats vs. HT-2 rats (e, j and o) after VB treatment. The blue and red dashed lines represented variations of 20% and 100%, respectively. Metabolites abbreviation: 3-HB: 3-Hydroxybutyrate; Ace: acetate; Ala: alanine; Arg: arginine; Bet: betaine; Cr: creatine; Cho: choline; Cit: citrate; DMK: acetone; Fum: fumarate; Glc: glucose; Gle: glycerol; Gln: glutamine; Glu: glutamate; Gly: glycine; GSH: glutathione; Hyp: hypoxanthine; Ino: inosine; Lac: Lactate; Lys: lysine; LDL/VLDL: low-density-lipoproteins/ very-low-density lipoproteins; Leu/Ile: Leucine/Isoleucine; MeOH: methanol; NAGP: N-Acetyl Glycoproteins; Nia: niacinamide; Phe: phenylalanine; Suc: succinate; Tyr: tyrosine; Tau: taurine; Val: valine; Uri: Uridine; Xan: xanthine.</p

Biochemical parameters measured in NC and VB treated groups.

<p>Data are presented as the mean ± SD with seven animals per group. ROS values expressed as the level of fluorescence/mg protein.</p><p>(*) <i>p</i> <0.05,</p><p>(**) <i>p</i> <0.01,</p><p>(***) <i>p</i> <0.001 compared to the NC group.</p><p>Biochemical parameters measured in NC and VB treated groups.</p

Photomicrographs of sections of myocardium (a-f) and liver (g-l) taken at 200 x magnification.

<p>(a) Normal myocardium cytoarchitecture; (b-f) Pathological changes in the myocardium after the administration of VB in different groups; (g) Normal liver cytoarchitecture; (h-l) Pathological changes in the liver after the administration of VB in different groups. VB treated heart showed obviously dilated intercellular spaces (black arrow), abundant eosinophilic cytoplasm and marked inflammatory cell infiltrations (red arrow). Live showed moderate piecemeal necrosis (yellow arrow) and slight inflammatory cell infiltrations in the portal tracts (black arrow).</p