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排序方式: 共有1115条查询结果,搜索用时 31 毫秒
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Karolina Chrabąszcz Dr. Andrzej Błauż Martyna Gruchała Marcin Wachulec Dr. Błażej Rychlik Prof. Damian Plażuk 《Chemistry (Weinheim an der Bergstrasse, Germany)》2021,27(20):6254-6262
Two series of the ferrocenyl and ruthenocenyl analogues of etoposide bearing 1,2,3-triazolyl or aminoalkyl linker were synthesized and evaluated for their cytotoxic properties, influence on the cell cycle, ability to induce tubulin polymerization, and inhibition of topoisomerase II activity. We found that the replacement of the etoposide carbohydrate moiety with a metallocenyl group led to organometallic conjugates exhibiting differentiated antiproliferative activity. Biological studies demonstrated that two ferrocenylalkylamino conjugates were notably more active than etoposide, with submicromolar or low-micromolar IC50 values towards SW620, etoposide-resistant SW620E, and methotrexate-resistant SW620M cancer cell lines. Moreover, the simplest ferrocenylmethylamino conjugate exerted dual inhibitory action against tubulin polymerization and topoisomerase II activity while other studied compounds affected only topoisomerase II activity. 相似文献
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Małgorzata T. Kaczmarek Renata Jastrząb Wanda Radecka-Paryzek 《Journal of solution chemistry》2013,42(1):18-26
Formation of complexes between the lanthanide ions and N,N′-bis(salicylidene)-4-methyl-1,3-phenylenediamine ligand was studied in solution by pH potentiometry. The potentiometric titration was performed at 25.00 °C in 0.1 mol·dm?3 NaClO4 ionic strength and in DMSO:water (30:70 v:v) solvent mixture. N,N′-bis(salicylidene)-4-methyl-1,3-phenylenediamine ligand (H2L) occurs in three forms: fully or partially deprotonated and unionized. Computer analysis of potentiometric data indicated that in solution the lanthanide (Ln) complexes exist as LnL2, Ln(HL)2 and Ln(H2L)2 species. This observation appears to be in contrast to the solid-state behavior of these complexes prepared in a self-assembly process and structurally defined. Stability constants for La3+, Eu3+, Gd3+, Tb3+, Ho3+ and Lu3+ (Ln3+) complexes were determined. The order of stabilities of LnL2 species in terms of metal ions is La3+ > Eu3+ ≈ Gd3+ = Tb3+ < Ho3+ < Lu3+ with a prominent “gadolinium break”. 相似文献
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Agnieszka Wojciechowska Agnieszka Szuster-Ciesielska Monika Sztandera Romualda Bregier-Jarzębowska Anna Jarząb Tomasz Rojek Urszula K. Komarnicka Agnieszka Bojarska-Junak Julia Jezierska 《应用有机金属化学》2020,34(8):e5698
A search for new drugs that overcome the multidrug resistance of microorganisms or are effective against cancer cells prompted us to investigate the binary and ternary Cu(II) complexes containing L-arginine, [CuCl(L-Arg)(phen)]Cl·2H2O (phen = 1,10-phenanthroline) ( 1 ) and [Cu(L-Arg)2(H2O)]C2O4·6H2O ( 2 ), for which crystal and molecular structures were characterized previously. In order to discuss the biological function, the complexes have been screened for their antitumor activity against A549 (human lung cancer cells), HepG2 (human liver hepatocellular carcinoma cells) and antimicrobial activity. To identify the complexes forms existing in the solutions of 1 and 2 crystals, the results obtained from EPR, NIR–Vis–UV and MS (mass spectrometry) measurements were correlated with those from analysis of potentiometric titration of Cu(II)―L-Arg and Cu(II)―L-Arg―phen systems. This comprehensive study indicated that the [Cu(L-Arg)(phen)]2+ and [Cu(L-Arg)2]2+ species are dominant in the solution. Complexes 1 and 2 were found to present specific ligand-dependent cytotoxic and antiproliferative potential against cancer cells. They also show antibacterial activity against Gram-positive and Gram-negative bacteria as well as display antifungal properties. 相似文献
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Litak Grzegorz Margielewicz Jerzy Gąska Damian Yurchenko Daniil Dąbek Krzysztof 《Nonlinear dynamics》2020,102(4):2125-2142
Nonlinear Dynamics - This paper examines the oscillations of a spherical pendulum with horizontal Lissajous excitation. The pendulum has two degrees of freedom: a rotational angle defined in the... 相似文献
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Lipophilicity study of eight cephalosporins by reversed‐phase thin‐layer chromatographic method 下载免费PDF全文
Monika Dąbrowska Łukasz Komsta Jan Krzek Kinga Kokoszka 《Biomedical chromatography : BMC》2015,29(11):1759-1768
The lipophilicity (RM0) and specific hydrophobic surface area for the representatives of four generation cephalosporins have been determined by reversed‐phase thin‐layer chromatography, and the effect of different mobile‐phase modifiers (such as methanol, acetonitrile, acetone, 1,4‐dioxane and 2‐propanol) on the retention has been studied. The compounds studied showed typical retention behavior; their RM values decreased linearly with increasing concentration of the organic modifier in the eluent. The linear correlations between the volume fraction of the organic solvent and the RM values over a limited range were established for each solute, resulting in high values of correlation coefficients (>0.95 in most cases). RM values were determined by various concentrations of organic modifier, and the correlation obtained was extrapolated to 0% of organic modifier. Chromatographically established logP (RM0) parameters were compared with computationally calculated partition coefficients values (AClogP, ALOGP, KOWWIN, ALOGPs, XLOGP2, MLOGP and XLOGP3) and experimental octanol–water logP values (measured by the shake flask method). The received results demonstrate that RP‐TLC may be a good alternative technique for analytics in describing the lipophilic nature of investigated cephalosporins as well as the activity. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
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