13 research outputs found
Tris(boratabenzene) Lanthanum Complexes: Synthesis, Structure, and Reactivity
A series of trisÂ(boratabenzene) lanthanum
complexes were synthesized
and structurally characterized. Salt elimination of anhydrous LaCl<sub>3</sub> with LiÂ[C<sub>5</sub>H<sub>5</sub>BR] (R = H, NEt<sub>2</sub>) provided trisÂ(boratabenzene) lanthanum complexes [C<sub>5</sub>H<sub>5</sub>BH]<sub>3</sub>ÂLaLiCl (<b>1</b>) and [C<sub>5</sub>H<sub>5</sub>BNEt<sub>2</sub>]<sub>3</sub>ÂLaLiClÂ(THF)
(<b>2</b>) in high yields. Hydroboration of 1-hexene or 3-hexyne
with <b>1</b> gave the alkyl- or alkenyl-functionalized boratabenzene
lanthanum complexes, [C<sub>5</sub>H<sub>5</sub>BÂ(CH<sub>2</sub>)<sub>5</sub>CH<sub>3</sub>]<sub>3</sub>ÂLaLiClÂ(THF) (<b>3</b>) and [C<sub>5</sub>H<sub>5</sub>BCÂ(C<sub>2</sub>H<sub>5</sub>)î—»CHÂ(C<sub>2</sub>H<sub>5</sub>)]<sub>3</sub>ÂLaLiClÂ(THF) (<b>4</b>), in good yields. Hydroboration of <i>N</i>,<i>N</i>′-diisopropylcarbodiimide with <b>1</b> gave the monohydroboration
product [C<sub>5</sub>H<sub>5</sub>BNÂ(<sup><i>i</i></sup>Pr)ÂCHNÂ(<sup><i>i</i></sup>Pr)]Â[C<sub>5</sub>H<sub>5</sub>BH]<sub>2</sub>La (<b>5</b>) due to the steric
bulk of the [C<sub>5</sub>H<sub>5</sub>BNÂ(<sup><i>i</i></sup>Pr)ÂCHNÂ(<sup><i>i</i></sup>Pr)]<sup>−</sup> ligand. Complex <b>5</b> can undergo further hydroboration
with 3-hexyne or dehydrogenative coupling with phenyl acetylene to
afford [C<sub>5</sub>H<sub>5</sub>BNÂ(<sup><i>i</i></sup>Pr)ÂCHNÂ(<sup><i>i</i></sup>Pr)]Â[C<sub>5</sub>H<sub>5</sub>BCÂ(C<sub>2</sub>H<sub>5</sub>)î—»CHÂ(C<sub>2</sub>H<sub>5</sub>)]<sub>2</sub>La (<b>6</b>) or [C<sub>5</sub>H<sub>5</sub>BNÂ(<sup><i>i</i></sup>Pr)ÂCHNÂ(<sup><i>i</i></sup>Pr)]Â[C<sub>5</sub>H<sub>5</sub>BCî—¼CPh)]<sub>2</sub>La (<b>7</b>)
Synthesis and Structure of Silicon-Bridged Boratabenzene Fluorenyl Rare-Earth Metal Complexes
A silicon-bridged
boratabenzene fluorenyl ligand [Me<sub>2</sub>SiÂ(C<sub>13</sub>H<sub>8</sub>)Â(C<sub>5</sub>H<sub>4</sub>BNEt<sub>2</sub>)]<sup>2–</sup> (<b>L</b><sup>2–</sup>) was designed
and synthesized. By employment of this ligand, two
divalent rare-earth metal complexes [Me<sub>2</sub>SiÂ(C<sub>13</sub>H<sub>8</sub>)Â(C<sub>5</sub>H<sub>4</sub>BNEt<sub>2</sub>)]ÂLnÂ(THF)<sub>2</sub> (Ln = Sm (<b>1</b>), Yb (<b>2</b>)) were obtained from salt metathesis of K<sub>2</sub>[Me<sub>2</sub>SiÂ(C<sub>13</sub>H<sub>8</sub>)Â(C<sub>5</sub>H<sub>4</sub>BNEt<sub>2</sub>)] (<b>K</b><sub><b>2</b></sub><b>L</b>) with LnI<sub>2</sub>Â(THF)<sub>2</sub> in THF.
Complex <b>2</b> undergoes redox reaction with cyclooctatetraene
to give a trivalent Yb complex [(C<sub>8</sub>H<sub>8</sub>)ÂYb]<sub>2</sub>Â[μ-{Me<sub>2</sub>SiÂ(C<sub>13</sub>H<sub>8</sub>)Â(C<sub>5</sub>H<sub>4</sub>BNEt<sub>2</sub>)}<sub>2</sub>] (<b>3</b>), accompanied with oxidative coupling of two fluorenyl
groups. A series of chloro-bridged trimeric trivalent rare-earth metal
complexes [LiÂ(THF)<sub>4</sub>]<sub>2</sub>Â[{[Me<sub>2</sub>SiÂ(C<sub>13</sub>H<sub>8</sub>)Â(C<sub>5</sub>H<sub>4</sub>BNEt<sub>2</sub>)]ÂLnÂ(μ-Cl)ÂLiÂ(THF)<sub>3</sub>}<sub>3</sub>Â(μ-Cl)<sub>3</sub>Â(μ<sub>3</sub>-Cl)<sub>2</sub>] (Ln = Nd (<b>4</b>), Sm (<b>5</b>), and Gd (<b>6</b>)) were synthesized by reactions of Li<sub>2</sub>[Me<sub>2</sub>SiÂ(C<sub>13</sub>H<sub>8</sub>)Â(C<sub>5</sub>H<sub>4</sub>BNEt<sub>2</sub>)] (<b>Li</b><sub><b>2</b></sub><b>L</b>) with LnCl<sub>3</sub> in THF. Treatment of K<sub>2</sub>[Me<sub>2</sub>SiÂ(C<sub>13</sub>H<sub>8</sub>)Â(C<sub>5</sub>H<sub>4</sub>BNEt<sub>2</sub>)] (<b>K</b><sub><b>2</b></sub><b>L</b>) with LnI<sub>3</sub>(THF)<sub><i>n</i></sub> gave the
monomeric complexes [Me<sub>2</sub>SiÂ(C<sub>13</sub>H<sub>8</sub>)Â(C<sub>5</sub>H<sub>4</sub>BNEt<sub>2</sub>)]ÂLnIÂ(THF)
(Ln = La (<b>7</b>), Nd (<b>8</b>), Sm (<b>9</b>), and Gd (<b>10</b>)). These iodides were subsequently reacted
with KÂ[CH<sub>2</sub>C<sub>6</sub>H<sub>4</sub>-<i>o</i>-NMe<sub>2</sub>] to afford THF coordinated benzyl complexes [Me<sub>2</sub>SiÂ(C<sub>13</sub>H<sub>8</sub>)Â(C<sub>5</sub>H<sub>4</sub>BNEt<sub>2</sub>)]ÂLnÂ(CH<sub>2</sub>C<sub>6</sub>H<sub>4</sub>-<i>o</i>-NMe<sub>2</sub>)Â(THF) (Ln
= La (<b>11</b>), Nd (<b>12</b>), and Gd (<b>13a</b>)) and non-THF coordinated complex [Me<sub>2</sub>SiÂ(C<sub>13</sub>H<sub>8</sub>)Â(C<sub>5</sub>H<sub>4</sub>BNEt<sub>2</sub>)]ÂGdÂ(CH<sub>2</sub>C<sub>6</sub>H<sub>4</sub>-<i>o</i>-NMe<sub>2</sub>) (<b>13b</b>)
Synthesis and Structure of Silicon-Bridged Boratabenzene Fluorenyl Rare-Earth Metal Complexes
A silicon-bridged
boratabenzene fluorenyl ligand [Me<sub>2</sub>SiÂ(C<sub>13</sub>H<sub>8</sub>)Â(C<sub>5</sub>H<sub>4</sub>BNEt<sub>2</sub>)]<sup>2–</sup> (<b>L</b><sup>2–</sup>) was designed
and synthesized. By employment of this ligand, two
divalent rare-earth metal complexes [Me<sub>2</sub>SiÂ(C<sub>13</sub>H<sub>8</sub>)Â(C<sub>5</sub>H<sub>4</sub>BNEt<sub>2</sub>)]ÂLnÂ(THF)<sub>2</sub> (Ln = Sm (<b>1</b>), Yb (<b>2</b>)) were obtained from salt metathesis of K<sub>2</sub>[Me<sub>2</sub>SiÂ(C<sub>13</sub>H<sub>8</sub>)Â(C<sub>5</sub>H<sub>4</sub>BNEt<sub>2</sub>)] (<b>K</b><sub><b>2</b></sub><b>L</b>) with LnI<sub>2</sub>Â(THF)<sub>2</sub> in THF.
Complex <b>2</b> undergoes redox reaction with cyclooctatetraene
to give a trivalent Yb complex [(C<sub>8</sub>H<sub>8</sub>)ÂYb]<sub>2</sub>Â[μ-{Me<sub>2</sub>SiÂ(C<sub>13</sub>H<sub>8</sub>)Â(C<sub>5</sub>H<sub>4</sub>BNEt<sub>2</sub>)}<sub>2</sub>] (<b>3</b>), accompanied with oxidative coupling of two fluorenyl
groups. A series of chloro-bridged trimeric trivalent rare-earth metal
complexes [LiÂ(THF)<sub>4</sub>]<sub>2</sub>Â[{[Me<sub>2</sub>SiÂ(C<sub>13</sub>H<sub>8</sub>)Â(C<sub>5</sub>H<sub>4</sub>BNEt<sub>2</sub>)]ÂLnÂ(μ-Cl)ÂLiÂ(THF)<sub>3</sub>}<sub>3</sub>Â(μ-Cl)<sub>3</sub>Â(μ<sub>3</sub>-Cl)<sub>2</sub>] (Ln = Nd (<b>4</b>), Sm (<b>5</b>), and Gd (<b>6</b>)) were synthesized by reactions of Li<sub>2</sub>[Me<sub>2</sub>SiÂ(C<sub>13</sub>H<sub>8</sub>)Â(C<sub>5</sub>H<sub>4</sub>BNEt<sub>2</sub>)] (<b>Li</b><sub><b>2</b></sub><b>L</b>) with LnCl<sub>3</sub> in THF. Treatment of K<sub>2</sub>[Me<sub>2</sub>SiÂ(C<sub>13</sub>H<sub>8</sub>)Â(C<sub>5</sub>H<sub>4</sub>BNEt<sub>2</sub>)] (<b>K</b><sub><b>2</b></sub><b>L</b>) with LnI<sub>3</sub>(THF)<sub><i>n</i></sub> gave the
monomeric complexes [Me<sub>2</sub>SiÂ(C<sub>13</sub>H<sub>8</sub>)Â(C<sub>5</sub>H<sub>4</sub>BNEt<sub>2</sub>)]ÂLnIÂ(THF)
(Ln = La (<b>7</b>), Nd (<b>8</b>), Sm (<b>9</b>), and Gd (<b>10</b>)). These iodides were subsequently reacted
with KÂ[CH<sub>2</sub>C<sub>6</sub>H<sub>4</sub>-<i>o</i>-NMe<sub>2</sub>] to afford THF coordinated benzyl complexes [Me<sub>2</sub>SiÂ(C<sub>13</sub>H<sub>8</sub>)Â(C<sub>5</sub>H<sub>4</sub>BNEt<sub>2</sub>)]ÂLnÂ(CH<sub>2</sub>C<sub>6</sub>H<sub>4</sub>-<i>o</i>-NMe<sub>2</sub>)Â(THF) (Ln
= La (<b>11</b>), Nd (<b>12</b>), and Gd (<b>13a</b>)) and non-THF coordinated complex [Me<sub>2</sub>SiÂ(C<sub>13</sub>H<sub>8</sub>)Â(C<sub>5</sub>H<sub>4</sub>BNEt<sub>2</sub>)]ÂGdÂ(CH<sub>2</sub>C<sub>6</sub>H<sub>4</sub>-<i>o</i>-NMe<sub>2</sub>) (<b>13b</b>)
MOESM1 of IL-33 reflects dynamics of disease activity in patients with autoimmune hemolytic anemia by regulating autoantibody production
Additional file 1: Figures. Gating strategy for anti-RBC antibody analysis, serum levels of sST2 in AIHA patients, Th2 cytokines in AIHA mice co-injected with IL-33 protein or IL-33 neutralizing antibody, B cell response to IL-33 stimulation or IL-33 blockade, and effect of IL-6 on IL-33-mediated autoantibody production were presented
MOESM1 of MicroRNA-125b promotes tumor metastasis through targeting tumor protein 53-induced nuclear protein 1 in patients with non-small-cell lung cancer
Additional file 1: Figure S1. Expressions of miR-125b and TP53INP1 in isolated NSCLC cells were determined by qPCR and analyzed for their negative correlation
<sup>18</sup>F‑Alanine Derivative Serves as an ASCT2 Marker for Cancer Imaging
Amino
acids derivative are well established molecular probes for
diagnosis of a variety of cancer using positron emission tomography
(PET). Recently, boramino acid (BAAs) was found as a prospective molecular
platform for developing PET tracer. The objective of this study was
to develop a <sup>18</sup>F-labeled alanine derivative through displacing
its carboxylate by trifluoroborate as a selective ASCT2 marker for
cancer imaging. <sup>18</sup>F-Ala-BF<sub>3</sub> was first evaluated
in healthy FVB/N mice <i>in vivo</i>, exhibiting rapid renal
clearance with almost negligible uptake in stomach (1.53 ± 0.31%ID/g).
Notable uptake was observed in thyroid (3.71 ± 0.49%ID/g, 40
min post injection), of which the uptake was significantly inhibited
by co-injection with natural L-alanine. In addition, we further established <sup>18</sup>F-Ala-BF<sub>3</sub> on a human gastric cancer cell (BGC-823)
xenografts bearing mouse model. Dynamic PET-CT scan revealed the optimal
time window for tumor imaging, it was between 40 and 60 min post injection,
when the BGC-823 xenografts uptake was 5.49 ± 1.47%ID/g (<i>n</i> = 4), and the tumor-to-stomach, tumor-to-blood, tumor-to-muscle,
and tumor-to-brain ratios were 3.27 ± 1.53, 3.80 ± 1.48,
3.47 ± 1.48, and 6.20 ± 1.47, respectively
Expression of hematopoietic surface markers in E8-10 (embryonic day 8–10) murine yolk sacs.
<p>Representative flow cytometric data from more than three independent analyses were shown.</p
Exposure to BQ upregulated Nrf2 protein expression and caused Nrf2 nuclear accumulation.
<p>Western Blot analysis of nuclear and cytoplasmic extracts from YS-HSCs treated with increasing concentrations of BQ for 6 hours. Histone H1 and GAPDH antibodies were used as loading controls for nuclear and cytoplasmic extracts, respectively. Left panels: representative blotting results. Densitometry of the immunoblotting results was shown in the right panels. Values are presented as means ± SDs (n = 3−5). * <i>P</i><0.05, **<i>P</i><0.01, # <i>P</i><0.001.</p
The ROS-generating NADPH oxidase NOX1 was induced by BQ.
<p>Immunoblotting data were shown in the upper panel. GAPDH was measured as loading control. Densitometry of immunoblotting results was shown in the lower panel. Values are presented as means ± SDs (n = 3−5). *, <i>P</i><0.05; **, <i>P</i><0.01; #, <i>P</i><0.001 compared with controls.</p
Increased expression of Nrf2-ARE pathway proteins were observed in the BQ-treated YS-HSCs.
<p>Induction of catalase, SOD1, SOD2, HMOX1 and NQO1 protein levels by BQ. Immunoblotting data were shown in the upper panel. GAPDH was measured as loading control. Densitometry of immunoblot results was shown in the lower panel. Values are presented as means ± SDs (n = 3−5). *, <i>P</i><0.05; **, <i>P</i><0.01; #, <i>P</i><0.001 compared with controls.</p