Indoxyl-glucuronides, upon treatment with β-glucuronidase under physiological conditions, are well known to afford the corresponding indigoid dye via oxidative dimerization. Here, seven indoxyl-glucuronide target compounds have been prepared along with 22 intermediates. Of the target compounds, four contain a conjugatable handle (azido-PEG, hydroxy-PEG, or BCN) attached to the indoxyl moiety, while three are isomers that include a PEG-ethynyl group at the 5-, 6-, or 7-position. All seven target compounds have been examined in indigoid-forming reactions upon treatment with β-glucuronidase from two different sources and rat liver tritosomes. Taken together, the results suggest the utility of tethered indoxyl-glucuronides for use in bioconjugation chemistry with a chromogenic readout under physiological conditions.
众所周知,吲哚酰葡萄糖醛酸在生理条件下经β-葡萄糖醛酸酶处理后,可通过氧化二聚作用生成相应的靛红染料。在这里,我们制备了七种吲哚酰-葡糖醛酸目标化合物和 22 种中间体。在这些目标化合物中,有四种含有连接到吲哚基上的可共轭柄(叠氮-PEG、羟基-PEG 或 BCN),另外三种是在 5、6 或 7 位上含有 PEG 乙炔基的异构体。在用两种不同来源的β-葡糖醛酸酶和大鼠肝脏三体处理后,对所有七种目标化合物的靛蓝形成反应进行了检测。总之,研究结果表明,在生理条件下,系链吲哚酰-葡糖醛酸可用于生物结合化学中的色原读数。