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1.
Chloride‐Selective Electrodes Based on “Two‐Wall” Aryl‐Extended Calix[4]Pyrroles: Combining Hydrogen Bonds and Anion–π Interactions to Achieve Optimum Performance 下载免费PDF全文
Jad Sabek Dr. Louis Adriaenssens Tomàs Guinovart Dr. Enrique J. Parra Prof. F. Xavier Rius Prof. Pablo Ballester Dr. Pascal Blondeau 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(1):448-454
The performance of chloride‐selective electrodes based on “two‐wall” aryl‐extended calix[4]pyrroles and multiwall carbon nanotubes is presented. The calix[4]pyrrole receptors bear two phenyl groups at opposite meso‐positions. When the meso‐phenyl groups are decorated with strong electron‐withdrawing substituents, attractive anion–π interactions may exist between the receptor’s aromatic walls and the sandwiched anion. These anion–π interactions are shown to significantly affect the selectivity of the electrodes. Calix[4]pyrrole, bearing a p‐nitro withdrawing group on each of the meso‐phenyl rings, afforded sensors that display anti‐Hofmeister behavior against the lipophilic salicylate and nitrate anions. Based on the experimental data, a series of principles that help in predicting the suitability of synthetic receptors for use as anion‐specific ionophores is discussed. Finally, the sensors deliver excellent results in the direct detection of chloride in bodily fluids. 相似文献
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Solubility and Crystallizability: Facile Access to Functionalized π‐Conjugated Compounds with Chlorendylimide Protecting Groups 下载免费PDF全文
Dr. Jan Gebers Damien Rolland Dr. Roman Marty Dr. Stéphane Suàrez Luca Cervini Dr. Rosario Scopelliti Dr. Jan Cornelius Brauer Prof. Dr. Holger Frauenrath 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(4):1542-1553
Functional π‐conjugated molecules are relevant for the preparation of new organic electronic materials with improved performance. However, their synthesis is often rendered difficult by their inherently low solubility, and the permanent attachment of solubilizing groups may change the properties of the material. Here, we introduced the chlorendylimidyl moiety as a new temporary protecting group for the straightforward large‐scale synthesis of protected quarter‐, sexi‐, octathiophene, and perylene bisimide diamine and dicarboxylic acid derivatives. The obtained chlorendylimides and chlorendylimidyl active esters were highly soluble in organic solvents, and optical spectroscopy confirmed the low tendency of the compounds to aggregate in solution. At the same time, they could be conveniently purified by recrystallization or precipitation. Single‐crystal X‐ray structures obtained for most compounds showed supramolecular motifs highlighting the role of the rigid, polychlorinated chlorendyl moieties in their crystallization. The obtained protected diamine and dicarboxylic acid derivatives were easily deprotected and converted into various amide‐substituted oligothiophenes and perylene bisimides that are of interest as new functional materials for organic electronic thin film or nanowire devices. 相似文献
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Ariadna Lázaro Cristina Balcells Dr. Josefina Quirante Prof. Josefa Badia Prof. Laura Baldomà Dr. Jas S. Ward Prof. Kari Rissanen Dr. Mercè Font-Bardia Prof. Laura Rodríguez Dr. Margarita Crespo Prof. Marta Cascante 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(9):1947-1952
Platinum-based chemotherapy persists to be the only effective therapeutic option against a wide variety of tumours. Nevertheless, the acquisition of platinum resistance is utterly common, ultimately cornering conventional platinum drugs to only palliative in many patients. Thus, encountering alternatives that are both effective and non-cross-resistant is urgent. In this work, we report the synthesis, reduction studies, and luminescent properties of a series of cyclometallated (C,N,N′)PtIV compounds derived from amine–imine ligands, and their remarkable efficacy at the high nanomolar range and complete lack of cross-resistance, as an intrinsic property of the platinacycle, against multiplatinum-resistant colorectal cancer (CRC) and castration-resistant prostate cancer (CRPC) metastatic cell lines generated for this work. We have also determined that the compounds are effective and selective for a broader cancer panel, including breast and lung cancer. Additionally, selected compounds have been further evaluated, finding a shift in their antiproliferative mechanism towards more cytotoxic and less cytostatic than cisplatin against cancer cells, being also able to oxidize cysteine residues and inhibit topoisomerase II, thereby holding great promise as future improved alternatives to conventional platinum drugs. 相似文献
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Dr. Júlia Mayans Dr. Constantinos C. Stoumpos Dr. Mercé Font-Bardia Prof. Albert Escuer 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(49):11158-11169
An anionic hexanuclear NiII metallamacrocycle with endo and exo linking sites has been employed as a building block to generate a series of capsules and bowls of nanometric size. The supramolecular arrangement of the {Ni6} rings was tailored by the size of the alkali cations, showing the transition from {Ni6-M2-Ni6} capsules (M=LiI and NaI) to {Ni6-M} bowls (M=KI and CsI). The alkyl co-cations are determinant to stabilize the assemblies by means of CH⋅⋅⋅π interactions on the exo side of the metallamacrocycles. The effect on the topology of the supramolecular assemblies of the cation size, cation charge, Et3NH+ or Me4N+ counter cations has been analyzed. Magnetic measurements reveal the presence of ferromagnetic and antiferromagnetic interactions inside the rings that allow a S=0 ground state. 相似文献