Three structurally similar compounds, 1–3, bearing a fluorescence chromophore to which are appended morpholine, thiomorpholine and methylpiperazine substituents, display opposite fluorescence responses to pH changes, in contrast to that observed for fluorescein; 1 and 2 have extremely high binding selectivity towards Ag+ ions and show completely different fluorescent and colorimetric changes upon addition of Ag+, and the differences are proposed to be associated with different binding modes of 1 and 2 to this metal ion.
1 和 2 对 Ag+ 离子具有极高的结合选择性,在加入 Ag+ 时显示出完全不同的荧光和比色变化,这种差异被认为与 1 和 2 与该
金属离子的不同结合模式有关。