Fares Mohamed, Wu Xin, McNaughton Daniel A, Gilchrist Alexander M, Lewis William, Keller Paul A, Arias-Betancur Alain, Fontova Pere, Pérez-Tomás Ricardo, Gale Philip A
School of Chemistry, The University of Sydney, Sydney, New South Wales 2006, Australia.
School of Chemistry & Molecular Bioscience, Molecular Horizons, University of Wollongong, and Illawarra Health & Medical Research Institute Wollongong, NSW 2522, Australia.
Org Biomol Chem. 2023 Mar 22;21(12):2509-2515. doi: 10.1039/d3ob00128h.
A series of fluorescent coumarin bis-ureas 1-4 have been synthesised, and their anion transport properties studied. The compounds function as highly potent HCl co-transport agents in lipid bilayer membranes. Single crystal X-ray diffraction of compound 1 showed antiparallel stacking of the coumarin rings, stabilised by hydrogen bonds. Binding studies, using H-NMR titration, showed moderate chloride binding in DMSO-/0.5% with 1 : 1 binding mode (for transporter 1) and 1 : 2 binding mode (host: guest, for transporters 2-4). We examined the cytotoxicity of compounds 1-4 against three cancer cell lines, lung adenocarcinoma (A549), colon adenocarcinoma (SW620) and breast adenocarcinoma (MCF-7). The most lipophilic transporter, 4 showed a cytotoxic effect against all three cancer cell lines. Cellular fluorescence studies showed compound 4 crossed the plasma membrane and localised in the cytoplasm after a short time. Interestingly, compound 4, lacking any lysosome targeting groups, was co-localised with LysoTracker Red at 4 and 8 h in the lysosome. Cellular anion transport of compound 4 was assessed by measuring intracellular pH and showed a decrease in cellular pH, which may be due to the capacity of transporter 4 to co-transport HCl across biological membranes, as evidenced by the liposomal studies.
已合成了一系列荧光香豆素双脲1-4，并研究了它们的阴离子转运特性。这些化合物在脂质双层膜中作为高效的HCl共转运剂发挥作用。化合物1的单晶X射线衍射显示香豆素环的反平行堆积，通过氢键稳定。使用H-NMR滴定的结合研究表明，在DMSO-/0.5%中，以1:1结合模式（对于转运体1）和1:2结合模式（主体：客体，对于转运体2-4）存在适度的氯离子结合。我们研究了化合物1-4对三种癌细胞系的细胞毒性，即肺腺癌（A549）、结肠腺癌（SW620）和乳腺腺癌（MCF-7）。亲脂性最强的转运体4对所有三种癌细胞系均显示出细胞毒性作用。细胞荧光研究表明，化合物4在短时间后穿过质膜并定位于细胞质中。有趣的是，缺乏任何溶酶体靶向基团的化合物4在4小时和8小时时与溶酶体中的LysoTracker Red共定位。通过测量细胞内pH评估化合物4的细胞阴离子转运，结果显示细胞内pH降低，这可能是由于转运体4能够跨生物膜共转运HCl，脂质体研究证明了这一点。
