Discovery of a sensitive Cu(<scp>ii</scp>)-cyanide “off–on” sensor based on new C-glycosyl triazolyl bis-amino acid scaffold
作者:Yan-Hui Tang、Yi Qu、Zhuo Song、Xiao-Peng He、Juan Xie、Jianli Hua、Guo-Rong Chen
DOI:10.1039/c1ob06242e
日期:——
A new functional glycosyl peptidomimetic, featuring a C-glucosyl 1,4-dimethoxynaphthalene backbone in conjugation with two triazolyl phenylalanine moieties on its adjacent C3,4-positions, was readily synthesized via click chemistry. Primary optical measurements indicated that the fluorescence of the ester form of this probe (4) could be selectively quenched by Pb2+. In contrast, the fluorescence intensity of its analog 5 with released carboxylic groups was uniquely diminished by Cu2+ with remarkably enhanced sensitivity and selectivity. Moreover, subsequent addition of cyanide to the methanol solution of the resulting Cu2+-5 complex induced its fluorescence recovery with a nanomolar detection limit, which was two orders of magnitude smaller than the regulated concentration limit of CNâ in drinking water. This suggests the promising applicability of C-glycosyl bis-triazolyl amino acid scaffold in the future design and exploration of sensitive âoffâonâ Cu(II)-cyanide chemosensors.
通过点击化学,我们很容易合成了一种新的功能性糖基肽模拟物,其特点是在相邻的 C3、4 位上以 C-葡萄糖基 1,4-二甲氧基萘为骨架与两个三唑基苯丙氨酸共轭。初级光学测量结果表明,这种探针的酯形式(4)的荧光可被 Pb2+ 选择性地淬灭。相比之下,其类似物 5 带有释放的羧基,其荧光强度被 Cu2+ 独特地减弱,灵敏度和选择性显著提高。此外,在生成的 Cu2+-5 复合物的甲醇溶液中随后加入氰化物,可诱导其荧光恢复,检测限为纳摩尔,比饮用水中 CNâ 的规定浓度限小两个数量级。这表明,C-糖基双三唑基氨基酸支架在未来设计和探索灵敏的氰化铜(II)化学传感器方面具有广阔的应用前景。