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Thermochemistry, Electrochemistry, and Solution Chemistry
Published in W. M. Haynes, David R. Lide, Thomas J. Bruno, CRC Handbook of Chemistry and Physics, 2016
W. M. Haynes, David R. Lide, Thomas J. Bruno
Rubidium Rubidium amide Rubidium bromide Rubidium carbonate Rubidium chloride Rubidium fluoride Rubidium hydride Rubidium hydrogen fluoride Rubidium hydrogen sulfate Rubidium hydroxide Rubidium iodide Rubidium metaborate Rubidium nitrate Rubidium nitrite Rubidium oxide Rubidium perchlorate Rubidium peroxide Rubidium sulfate Rubidium superoxide Ruthenium Ruthenium(III) bromide Ruthenium(III) chloride Ruthenium(III) iodide Ruthenium(IV) oxide Ruthenium(VIII) oxide Salicylaldehyde Salicylaldoxime Samarium Samarium(III) chloride Samarium(III) fluoride Samarium(III) oxide Sarcosine Scandium
Tuning of Ruthenium – DMSO Complexes for Search of New Anticancer Agents
Published in Ajay Kumar Mishra, Lallan Mishra, Ruthenium Chemistry, 2018
On the other hand, topoisomerase II enzyme is crucial for the cellular division of rapidly growing proliferating tumor cells. Therefore, the inhibition of topo II has also been primary targeted for numerous antitumor agents (Larsen et al., 2003; Nitiss et al., 2009). The nuclear enzyme topoisomerase II is referred to as a “molecular engineer,” which is essential for DNA replication, repair, transcription, topological changes, and chromosomal segregation at mitosis under physiological condition (Spence, 2005). The topoisomerase catalyzes the transient double strand of DNA, transport it into an intact fragment of DNA and relegate cleaved strands. The enzyme is a combination of three domains: (1) N-terminal ATP-binding domain: various catalytic inhibitors reduce ATPase activity by blocking ATP from its binding site, (2) DNA-binding/cleaving domain: catalytic active site necessary for construction of covalent complex, and (3) C-terminal tail (Bailly, 2012). To understand the mechanism of action, two categories of Topo II inhibitors were studied in detail: (1) those that form DNA−Topo-II cleavable complex by binding with the topo II and stimulate the cleavage of double standard DNA (etoposide) (Zeglis, 2011), (2) other class, which includes catalytic inhibitors which antagonize the activity of enzyme to implement catalysis (merbarone) Larsen (2003). The wide range of topoisomerase inhibitors, including etoposide, mitoxantrone, amsacrine, idarubicin, and doxorubicin mainly destroy all cells in DNA replication and sensing of DNA in protein production or DNA-damage repair (Li, 2001). The topoisomerase inhibition is fundamentally influenced by the nature of complexes, ligands, and available uncoordinated sites in the skeleton of coordinated ligands. In this connection, Jayaraju et al. reported topo II inhibitor salicylaldoxime cobalt complex (CoSAL), which results in cleavable complex formation by interacting oxime moiety of the salicylaldoxime ligand with the topo II (Jayaraju, 1999). Furthermore, (η6-benzene)Ru(DMSO)Cl2 (Fig. 10.3)displayed strong DNA-binding affinity together with cross-linking with topoisomerase II and inhibited the activity of topoisomerase II by cleavage complex formation (Gopal, 2002). Gopal et al. suggested that ruthenium complex interacts with DNA and forms cross-links with topoisomerase II. The complex exhibited antiproliferative activity in two human cancer cell lines Colo-205 (colon adenocarcinoma) and ZR-75-1 (breast carcinoma) in vitro, but it is inconclusive if there is a direct link to its ability to inhibit topoisomerase II activity (Gopal, 2002).
Application of resins with functional groups in the separation of metal ions/species – a review
Published in Mineral Processing and Extractive Metallurgy Review, 2018
Rene A. Silva, Kelly Hawboldt, Yahui Zhang
Oxime groups exist in hydroxy, ketoxime, and aldoxime forms with bonding preferences to metals with oxidation state of three and higher. This property allows the removal of ferric ions from base-metal solutions and the adsorption of heavy metals from wastewaters. Srivastava and Rao (1990) reported that salicylaldoxime groups present metal ion selectivity of Pb2+ = Zn2+ = Ni2+ > Cu2+ > Cd2+ > Pd2+ > Mn2+ > Fe2+ > CO2+. However, Smith et al. (2003) reported that phenolic oxime groups allow complex formation with metals V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Ga, Mo, Pd, Sn, and Pt. Commercial resin Purolite S910, containing amidoxime groups, is commercialized for the selective adsorption of As3+, Fe3+, Cu2+, Pb2+, and Cd2+. Kagaya et al. (2015) reported that oxime groups also have the potential for selective U and Ga adsorption. Likewise, Kabay and Egawa (1994) reported that amidoxime groups selectively adsorbed U and other metal ions over several alkaline-earth metal ions in samples from seawater.
A Review on Separation of Gallium and Indium from Leach Liquors by Solvent Extraction and Ion Exchange
Published in Mineral Processing and Extractive Metallurgy Review, 2018
Thi Hong Nguyen, Man Seung Lee
According to Section 2, the formation of cationic, anionic, and neutral species of In(III) and Ga(III) in the aqueous solution depends on the acidity and types of ligand. Therefore, acidic, neutral, and basic extractants have been employed for the extraction and separation of In(III) and Ga(III) from different solutions. In the pH range of 2–4, the extraction of Ga(III) was quantitative with 2-ethylhexyl phosphonic acid mono 2-ethylhexyl ester (PC 88A), di(2-ethylhexyl)phosphoric acid (D2EHPA), 2-ethylhexyl 2-ethylhexylphosphonic acid (EHEHPA), di(2,4.4ʹ-trimethylpentyl)phosphinic acid (DTMPPA), 2-metyl-8-quinolinol derivatives, and a mixture of 5-dodecyl-salicylaldoxime and 2-hydroxy-5-nonylacetophenone oxime (LIX 973N) (Inoue et al. 1988a; Jayachandran and Dhadke 1998; Alguacil 1999; Choi and Ohashi 2000). Primary amines and Cyanex 921 were effective to extract Ga(III) at high pH values, while high extraction efficiency of Ga(III) by a mixture of four trialkyphosphine oxides (Cyanex 923) and bis(2,4,4-trimethylpentyl)octylphosphine oxide (Cyanex 925) can be obtained from concentrated acid solutions (Mishra et al. 2000; Geidarov 2008; Ahmed et al. 2013).