[(1,4,7,10-tetraazacyclododecane-1-[(N-oxido-pyridine-2-yl)methyl]-4,7,10-triacetate)aquaeuropium(III)] | 817636-76-3

• 分子结构分类: 有机化合物 - 有机杂环化合物 - 吡啶及其衍生物
• 英文名称: [(1,4,7,10-tetraazacyclododecane-1-[(N-oxido-pyridine-2-yl)methyl]-4,7,10-triacetate)aquaeuropium(III)]
• 英文别名: Eu(10-[(1-oxidopyridin-2-yl)methyl]-1,4,7,10-tetraazacyclododecane-1,4,7-triacetate)]
• CAS: 817636-76-3
• 化学式: C₂₀H₃₀EuN₅O₈
• 分子量: 620.447
• InChiKey: ZULZGTQMUSYZDE-UHFFFAOYSA-K

计算性质

• 辛醇/水分配系数(LogP)：
  None
• 重原子数：
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• 可旋转键数：
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• 环数：
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• sp3杂化的碳原子比例：
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• 拓扑面积：
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• 氢给体数：
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• 氢受体数：
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反应信息

• 作为产物：
  描述：

  2-((4,7,10-tris(carboxymethyl)-1,4,7,10-tetraazacyclododecan-1-yl)methyl)pyridine-1-oxide 、 氯化铕(III) 在 KOH 作用下， 以 水 为溶剂， 以75%的产率得到[(1,4,7,10-tetraazacyclododecane-1-[(N-oxido-pyridine-2-yl)methyl]-4,7,10-triacetate)aquaeuropium(III)]
  参考文献：
  名称：

  Lanthanide(III) Complexes of Pyridine-N-Oxide Analogues of DOTA in Solution and in the Solid State. A New Kind of Isomerism in Complexes of DOTA-like Ligands

  摘要：

  The replacement of one of the acetate pendant arms with a 2-methylpyridine-N-oxide group in the molecule of H(4)dota significantly alters the coordination properties of the ligand in Ln(III) complexes. The structural properties of the complexes are investigated both in solution and in the solid state. The variable-temperature H-1 NMR spectra of Nd-III, Eu-III, and Yb-III complexes show that the twisted-square-antiprismatic (TSA) isomer is strongly destabilized and suppressed in solution and the complexes exist mostly as the square-antiprismatic (SA) isomers (98% for Eu-III at -35 degrees C). The exchange between the TSA and SA isomers is fast at room temperature compared to that of the NMR time scale. The flexibility of the six-membered chelate ring formed by coordination of the 2-methylpyridine-N-oxide group to the central ion allows two orientations of this pendant arm relative to the acetate arms: syn-SA (pyridine in the direction of the acetates) and anti-SA (pyridine opposite to the acetates). The syn-SA form was found in the X-ray structure of the Nd-III complex; the anti-SA forms were found in the structures of Dy-III, Tm-III, and Yb-III complexes. The UV-vis and H-1 NMR spectra of the Eu-III complex suggest that both forms are in dynamic equilibrium in solution. A derivatization of the pyridine-N-oxide group with a carboxylic group in the 4 position has no significant effect on the properties of the Ln(III) complexes.

  DOI：

  10.1021/ic801597z

文献信息

• Lanthanide(<scp>iii</scp>) complexes of a pyridine N-oxide analogue of DOTA: exclusive M isomer formation induced by a six-membered chelate ring
  作者：Miloslav Polášek、Jakub Rudovský、Petr Hermann、Ivan Lukeš、Luce Vander Elst、Robert N. Muller

  DOI：10.1039/b409996f

  日期：——

  The presence of a six-membered chelate ring involving a pyridine N-oxide moiety induces exclusive M isomer formation throughout the whole lanthanide series endowed with a fast water exchange in the case of the Gd(III) complex.

  涉及吡啶N-氧化物部分的六元螯合环的存在在整个镧系系列中诱导了唯一的M异构体形成，而在Gd（III）配合物的情况下，则可以进行快速的水交换。