Cytotoxicity of η-areneruthenium-based molecules to glioblastoma cells and their recognition by multidrug ABC transporters
摘要:
A new series of amphiphilic eta(6)-areneruthenium(II) compounds containing phenylazo ligands (group I: compounds la, 1b, 2a and 2b) and phenyloxadiazole ligands (group II: compounds 3a, 3b, 4a and 4b) were synthesized and characterized for their anti-glioblastoma activity. The effects of the amphiphilic eta(6)-areneruthenium(II) complexes on the viability of three human glioblastoma cell lines, U251, U87MG and T98G, were evaluated. The azo-derivative ruthenium complexes (group I) showed high cytotoxicity to all cell lines, whilst most oxadiazole-derivative complexes (group II) were less cytotoxic, except for compound 4a. The cationic complexes 2a, 2b and 4b were more cytotoxic than the neutral complexes. Compounds 2a and 2b caused a significant reduction in the percentage of cells in the G0/G1 phase, with concomitant increases in the G2/M phase and fragmented DNA in the T98G cell line. The eta(6)-areneruthenium(11) compounds were also tested in cell lines that overexpress the multidrug ABC transporters P-gp, MRP1 and ABCG2. Compounds 2b and 4a were substrates for the P-gp protein, with resistance indexes of 8.6 and 1.9, respectively. Compound 2b was also a substrate for ABCG2 and MRP1 proteins, with lower resistance indexes (1.8 and 1.6, respectively). The contribution of multidrug ABC transporters to the cytotoxicity of compound 2b in T98G cells was evidenced, since verapamil (a characteristic inhibitor of MRP1) increased the cytotoxicity of compound 2b at concentrations up to 20 mu mol L-1, whilst GP120918 and Ko143 (specific inhibitors of P-gp and ABCG2, respectively) had no significant effect. In addition, we showed that compound 2b interacts with glutathione (GSH), which could explain its cellular efflux by MRP1. Our results showed that the amphiphilic eta(6)-areneruthenium(II) complexes are promising anti-glioblastoma compounds, especially compound 2b, which was cytotoxic for all three cell lines, although it is transported by the three main multidrug ABC transporters. (C) 2018 Elsevier Masson SAS. All rights reserved.
An Expeditious and Convenient One Pot Synthesis of 2,5-Disubstituted-1,3,4-oxadiazoles
作者:Sabir H. Mashraqui、Shailesh G. Ghadigaonkar、Rajesh S. Kenny
DOI:10.1081/scc-120021845
日期:2003.1.8
Abstract A convenient, one pot procedure is reported for the synthesis of a variety of 2,5-disubstituted-1,3,4-oxadiazoles by condensing mono-arylhydrazides with acid chlorides in HMPA solvent under the microwave heating. The yields are good to excellent, the process is rapid and does not need any added acid catalyst or dehydratingreagent.
Unsymmetrically 2,5-disubstituted1,3,4-oxadiazoles were efficiently synthesized from the cyclization–oxidation reaction of acyl hydrazones. Also, the synthesis of the title compounds was achieved by the condensation of acyl hydrazides and aromatic aldehydes in the presence of ceric ammonium nitrate in dichloromethane.
Direct Palladium‐Catalyzed C5‐Arylation of 1,3,4‐Oxadiazoles with Aryl Chlorides Promoted by Bis(di‐isopropylphosphino) Ferrocene
作者:Loris Gelin、Henri Sabbadin、Hélène Cattey、Paul Fleurat‐Lessard、Jean‐Cyrille Hierso、Julien Roger
DOI:10.1002/ejoc.202400212
日期:2024.6.3
The palladium-catalyzed direct arylation of 1,2,4-oxadiazoles proceeds efficiently at low catalyst loading (0.5 to 1 mol %) with the decisive assistance of sterically constrained ferrocenyldiphosphane ligands. This protocol tolerates electron-donating and electron-withdrawing substituents on the (heteroaryl)arylhalide.