Department of Chemistry Materials and Chemical Engineering "G. Natta", Politecnico di Milano, Via Mancinelli 7, 20131, Milano, Italy.
UniversitàTelematica e-Campus, Via Isimbardi 10, 22060, Novedrate, Como, Italy.
Chempluschem. 2020 Jun;85(6):1171-1178. doi: 10.1002/cplu.202000190.
Cyclodextrins (CDs), a class of cyclic oligosaccharides formed by α-(1,4) linked glucopyranose units, were functionalized with (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO) radicals to prepare water soluble supramolecular organic radical contrast agents (ORCAs) for the in vivo detection of glioma tumor in animal models. A first set of molecules (CDn1, n=6,7,8 is the number of both TEMPO and glucopyranose units) was studied by superconducting quantum interference devices (SQUID) magnetometry in order to define the role of the CD macrocycle on the effective magnetic moment (μ ). The μ value increased from 3.982 μ (CD61) to 4.522 μ (CD81) but was limited by intramolecular antiferromagnetic (AF) interactions. A set of water-soluble ORCAs (CDn8, n=6,7,8) was prepared by a sequence of thiol-ene and Cu(I)-catalyzed alkyne-azide "click" reactions. Their H water relaxivities r of these ORCAs were between 0.739 mM s (CD68) to 1.047 mM s (CD88) in D O/H O 9 : 1 (v : v) at 300 K. One of them (CD78) was tested on glioma-bearing rats with reduced side effects and good relaxivity in vivo.
环糊精（CDs）是一类由α-（1,4）连接的葡萄糖吡喃糖单元组成的环状低聚糖，其被（2,2,6,6-四甲基哌啶-1-基）氧自由基（TEMPO）功能化，以制备用于在动物模型中检测神经胶质瘤肿瘤的水溶性超分子有机自由基对比剂（ORCA）。一组分子（CDn1，n=6,7,8 是 TEMPO 和葡萄糖吡喃糖单元的数量）通过超导量子干涉器件（SQUID）磁强计进行了研究，以确定 CD 大环对有效磁矩（μ）的作用。μ 值从 3.982 μ（CD61）增加到 4.522 μ（CD81），但受到分子内反铁磁（AF）相互作用的限制。一组水溶性 ORCAs（CDn8，n=6,7,8）通过一系列硫醇-烯和 Cu（I）催化的炔烃-叠氮化物“点击”反应制备。它们在 300 K 时，在 D2O/H2O 9:1（v:v）中的 H 水弛豫率 r 在 0.739 mM s（CD68）至 1.047 mM s（CD88）之间。其中一种（CD78）在携带神经胶质瘤的大鼠中进行了测试，具有较低的副作用和良好的体内弛豫率。
