Synthesis and characterization of racemic mixture and meso isomers of bis(trans-2-aminocyclohexyl)aminepentaacetic acid and the stabilities of their Gd(III) complexes.
Synthesis and characterization of racemic mixture and meso isomers of bis(trans-2-aminocyclohexyl)aminepentaacetic acid and the stabilities of their Gd(III) complexes.
复制标题
双(反式-2-氨基环己基)胺五乙酸的外消旋混合物和内消旋异构体的合成、表征及其Gd(III)配合物的稳定性。
DOI：
10.1021/ic991189m
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发表时间：
2000
影响因子：
4.6
通讯作者：
Welch,MJ
中科院分区：
文献类型：
--
作者：
Sun,Y;Martell,AE;Reibenspies,JH;Reichert,DE;Welch,MJ
本文报道了两种多齿配体--双（反式-2-氨基环己基）氨基五乙酸的外消旋混合物和内消旋异构体的合成与表征。用直接电位法测定了它们的Gd（III）配合物的平衡常数。Gd（III）−Cycyracemicin 0.10 M KCl在25.0 °C时的形成常数（KML= [ML]/[M][L]）为1020.71;内消旋异构体的形成常数为1020.42。本文报道了（1 S，2S，1 ′ S，2 ′ S）-双（反式-2-氨基环己基）胺-N，N，N ′，N“，N "-五乙酸五叔丁酯（C_（42）H_（75）N_3 O_（10））的晶体结构。晶体属三斜晶系，空间群P1，晶胞参数a = 10.805（2）<$，B= 11.382（2）<$，c= 20.999（4）<$，α = 91.41（3）°，β = 98.23（3）°，γ = 113.88（3）°，V= 2327.8（8）<$3，Z= 2，Dx= 1.116 g mL-1。的钆配合物的晶体结构和来自分子力学的预测的结果进行了比较。
The synthesis and characterization of two multidentate ligands, the racemic mixture and meso isomers of bis(trans-2-aminocyclohexyl)aminepentaacetic acid, are described. Equilibrium constants for their Gd(III) complexes were determined by direct potentiometry. The formation constants (KML= [ML]/[M][L]) of Gd(III)−Cycyracemicin 0.10 M KCl at 25.0 °C is 1020.71; that for the meso isomer is 1020.42. The crystal structure of (1S,2S,1‘S,2‘S)-bis(trans-2-aminocyclohexyl)amine-N,N,N‘,N‘ ‘,N‘ ‘-pentaacetic acid, penta-tert-butyl ester (C42H75N3O10), is reported. This compound crystallizes in the triclinic system with space groupP1 with cell parametersa= 10.805(2) Å,b= 11.382(2) Å,c= 20.999(4) Å, α = 91.41(3)°, β = 98.23(3)°, γ = 113.88(3)°,V= 2327.8(8) Å3,Z= 2,Dx= 1.116 g mL-1. The results are compared to the crystal structures of the gadolinium complexes and the predictions derived from molecular mechanics.