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Zastosowanie chemii "klik" do syntezy biokoniugatów salinomycyny

Sulik Michał, Antoszczak Michał, Huczyński Adam

Wiadomości Chemiczne

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2022

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[Z] 76, 11-12

883--907

EN

Bioconjugation is a well-known method of designing new drug candidates for many different diseases, including cancer. The idea of the process is to join two or more bioactive molecules by means of a covalent bond. Thus, obtained hybrids often exhibit higher efficiency compared to that of the starting compounds. Recently, the use of click chemistry, especially Huisgen 1,3-dipolar cycloaddition, has attracted much attention for the synthesis of bioconjugates of natural compounds. The great advantage of this reaction is its high yield and enzymatic stability of the 1,2,3-triazole ring. Mild conditions of this reaction guarantee that it can be used to modify compounds with low stability, such as salinomycin – a representative of ionophore antibiotics. Salinomycin is a naturally occurring lipophilic compound isolated from Streptomyces albus. It is capable of forming complexes with metal cations and transport them across the lipid membranes. This process disturbs the intercellular Na+ /K+ concentration gradient and leads to apoptosis (programmed cell death). Salinomycin exhibits high anticancer activity, including efficiency against multidrug-resistant cancer cells and cancer stem cells of different origin. Chemical modification of the salinomycin skeleton to increase its biological activity is a very interesting research direction. Our review article is focused on the application of click chemistry for the synthesis of salinomycin bioconjugates with many different biologically active compounds (Cinchona alkaloids, nucleosides, triphenylphosphonium cation, betulinic acid and other ionophore antibiotics). Some of the obtained hybrids exhibit higher efficiency compared to that of the starting compounds, e.g., increased anticancer activity, the ability to overcome multi-drug resistance, or improved ionophoretic properties. These results are a good starting point for further research on the use of click chemistry in the synthesis of highly functional hybrids of natural compounds.

2

Biokoniugaty antybiotykow jonoforowych : cele, strategie syntezy i właściwości

Antoszczak M., Kordylas M., Huczyński A.

Wiadomości Chemiczne

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2018

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[Z] 72, 1-2

1--28

EN

Polyether ionophore antibiotics (ionophores) represent a large group of naturally- occurring lipophilic compounds which are able to form complexes with the metal cations and transport them across the lipid membranes. This process disturbs the intercellular Na+/K+ concentration gradient and intracellular pH, and leads to the mitochondrial damages, cell swelling, vacuolization and finally to apoptosis process. For this reason, ionophores are commonly used in veterinary medicine as the non-hormonal growth-promoting as well as coccidiostatic agents. In this group particularly interesting are monensin and salinomycin (Fig. 1) because of their proved anti-tumour activity, including efficiency against multidrug- -resistant cancer cells and cancer stem cells of different origin. Improved synthetic derivatives of both polyether ionophores are thus of considerable current interest. Selective derivatization of these structures whose display multiple reactive functional groups and, in the case of salinomycin, a sensitive tricyclic spiroketal ring system is however non-trivial. Even so, semi-synthetic analogs reported to date includes i.a. selective derivatization of the carboxyl group, the three hydroxyl groups, the ketone group, the alkene, and epimerization of the characteristic tricyclic salinomycin unit (for more details see: M. Antoszczak, A. Huczyński, B. Brzezinski, Wiad. Chem., 2017, 71, 629). On the other hand, as part of the original program to develop innovatory anti- -cancer pro-drugs and prompted by the idea that cancer cells may be individually effectively killed by monensin and salinomycin, a very interesting direction of research is bioconjugation of these ionophores. In this context, our review article is focused on the possible role of hybrids of both ionophore antibiotics with other biologically active substances (natural amino acids, Cinchona alkaloids, flavonoids, nucleosides) in anti-bacterial and anti-cancer treatment, and gives an overview of their properties.

3

Synteza i aktywność biologiczna pochodnych salinomycyny

Antoszczak M., Huczyński A., Brzezinski B.

Wiadomości Chemiczne

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2017

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[Z] 71, 7-8

629--661

EN

Polyether ionophore antibiotics (ionophores) represent a large group of naturally- occurring lipid-soluble compounds isolated from actinomycetes strains of Streptomyces genus. Ionophores are able to form complexes with the metal cations, especially sodium and potassium, and transport them across the lipid membranes according to electroneutral or electrogenic transport mechanism. This process disturbs the intercellular Na+/K+ concentration gradient and intracellular pH, leads to the mitochondrial injuries, cell swelling, vacuolization and finally to programmed cell death (apoptosis). For this reason, ionophore antibiotics found commercial use in veterinary medicine as coccidiostatic agents and non-hormonal growth promoters. In addition to the industrial use of ionophores, some of them effectively and selectively inhibit properties of different cancer cells as well as enhance the anti-cancer effects of radio- and/or chemotherapy. In this group, particularly interesting is salinomycin because of its potent anti-microbial and anti-cancer activity, including efficiency against multi-drug resistant cancer cells and cancer stem cells. A very interesting direction of research is the chemical modification of ionophore antibiotics, which can lead to obtaining various derivatives with better biological activity and lower toxicity than those of the starting substances. Because biological activity of ionophore antibiotics and their derivatives is strictly connected with the ability to form characteristic pseudocyclic structures around the complexed cations (host-guest complex), it is also important to establish the detailed information on these structures. In this context, our review article is focused on the possible role of salinomycin and its derivatives in anti-microbial as well as anti-cancer therapy, and gives an overview of the properties of this antibiotic.

4

Potentiometric membrane electrode for determination of nitrate based on 1,8-bis(salicylaldiminato)-3,6-dioxaoctane Ni(II) complex

Mazloum Ardakani M., Mashhadizadeh Ardakani M. H., Karimi M. A., Azimi M. S., Iranpoor F., Salvati-Niasari M.

Chemia Analityczna

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2008

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Vol. 53, No. 1

17-32

EN

The construction, performance, and applications of nitrate-selective electrode based on l,8-bis(salicyIaldiminato)-3,6-dioxaoctane Ni(II) complex as a carrier trapped in plasti-cized poly{ vinyl chloride) (PVC) matrix were described. The influence of membrane composition, pH, and potential interfering anions was investigated based on the response of the electrode. The electrode exhibited linear response with Nemstian slope of-58.7 š 0.7 mV per decade within the concentration range of nitrate ions of 8.0 x 10-6-1.0 mol L-1. The limit of detection was determined from the intersection of the extrapolated linear segments of the calibration plot, and equaled 8.0 x 10-6 -1.0 mol L-1. The response time of the electrode was < 15 s over the entire concentration range. The designed electrode could be used for at least three months without a significant potential drift. It exhibited good selectivity towards nitrate compared to other anions. It was applied as the indicator electrode in potentiometric determination of nitrate ions in real samples.

PL

Opisano konstrukcję, charakterystykę i zastosowania elektrody do oznaczania azotanów. Jako nośnik stosowano kompleks Ni(II) z l,8-bis(salicy!aldiminato)-3,6-dioksaoktanem w plastyfikowanym polichlorku winylu. Badano wpjyw składu membrany, pH i potencjalnie obecnych anionów na potencjał elektrody. Elektroda wykazuje nernstowskie nachylenie charakterystyki wynoszące-58,7 š 0,7 mV/dekade w zakresie stężeń 8.0 x l0-6-1.0. Granica wykrywalności wynzaczona na podstawie przecięcia liniowych odcinków krzywej kalibrowania wynosi 8.0 x 10-6 -1.0 mol L-1. Czas odpowiedzi elektrody w całym zakresie stężeń wynosi 15 s. Elektroda może być używana w ciągu co najmniej 3 miesięcy bez widocznej zmiany potencjału. Wykazuje dobrą selektywność wobec innych anionów. Elektroda została zastosowana do oznaczania azotanów w rzeczywistych próbkach.

5

Molecular Clusters to Nanomaterials

Singh N., Lee H., Suh S., Kołaski M., Kim K.

Polish Journal of Chemistry

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2007

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Vol. 81, nr 5-6

1021-1035

EN

Theoretical investigations of gas phase clusters enable the evaluation of intrinsic molecular properties and intermolecular interactions. Based on the microscopic determination of the properties of individual atoms, molecules, or clusters, one can predict the macroscopic properties of bulk matter. With the aid of theoretical insights into the interaction forces holding these clusters and subsequent properties of a large number of cluster systems (ranging from simple water clusters to large pi-systems), we have investigated the properties of various novel molecular systems including endo/exohedral fullerenes, nanotori, nonlinear optical materials, ionophores/receptors, polypeptides, enzymes, organic nanotubes, nanowires, and electronic and nano-mechanical molecular devices. This mini-review highlights some of the interesting results obtained in the course of our extensive theoretical investigations of clusters toward the molecular design approach of nanomaterials.

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AC-impedance studies on ion transfer across ionophore-based ion-selective membranes

Mikhelson K. N.

Chemia Analityczna

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2006

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Vol. 51, No. 6

853-867

EN

Fundamental complexities related to the studies on inter facial charge transfer at ionophore--based ion-selective electrode (ISE) membranes have been briefly discussed. The presented data obtained from ac-impedance studies on ISEs selective to K+, Na\ Li+, and Ca2+ ions have shown fast interfacial transfer of primary ions, and also of interfering ions, supporting the concept of fast establishment of interfacial electrochemical equilibrium towards all competing ions in the solution.

PL

Pokrótce omówiono podstawową trudność /wiązaną z badaniami nad między fazowy m przeniesieniem ładunku w zawierających jonofor membranach elektrod jonoselektywnych. Przedstawione dane uzyskane w badaniach ac-impedancyjnych ISE selektywnych najony K+. Na+, Li+, i Ca2+ sugerują szybkie między fazowe przeniesienie jonów głównych, jak również jonów przeszkadzających. potwierdzając koncepcje szybkiego ustalenia międzyfa-zowej równowagi elektrochemicznej wobec wszystkich konkurencyjnych jonów w roztworze.

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Membrane based on decyl-18-crown-6 for a potassium selective sensor

Hopârtean E., Pică E. M., Ana C., Cosma V., Hopârtean I.

Chemia Analityczna

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2001

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Vol. 46, No. 1

41-49

EN

Four kinds of 18-crown-6 derivatives were studied as ionophores in plasticized poly(vi-nyl chloride) (PVC) in order to obtain potassium selective membrane. The properties of the sensor were studied in detail. For the optimization of the selectivity toward K+ over Na+ the influence of the following factors was studied: nature and concentration of the ionophore; nature and concentration of the plasticizer and lipophilic salt addition. The potassium ion-selective membrane electrode was designed. The electrode has a fast and Nernstian response in the 1 x 10(-1)-2 x 10(-5) mol 1(-1) K+, after six months of continuous measurements. The change of pH in the range 2-10.5 does not affect the response of the electrode. The internal resistance of the electrode was measured. The electrode shows a good stability and can be used in the potentiometric determination.

PL

Badano cztery rodzaje pochodnych związku: 18-korona-6 jako jonofory w plastyfi-kowanym polichlorku winylu (PVC), w celu uzyskania membrany selektywnej względem jonów potasowych. Szczegółowo badano własności czujnika pomiarowego. W celu optymalizacji selektywności względem jonów K+ w porównaniu do jonów Na+ zbadano wpływ następujących parametrów: rodzaj i stężenie jonoforu, rodzaj i stężenie plasty-fikatora, oraz dodatek soli lipofilowej. Zaprojektowano jonoselektywną elektrodę membranową, selektywną względem jonów potasowych. Elektroda ma krótki czas odpowiedzi i nernstowską odpowiedź w granicach stężeń: 10(-1) x 10(-5) mol l(-1) K+ po sześciu miesiącach ciągłych pomiarów. Zmiana pH w granicach 2-10.5 nie wpływa na odpowiedź elektrody. Zmierzono wewnętrzną rezystancję elektrody. Elektrodę cechuje dobra trwałość i można ją używać do oznaczeń potencjometrycznych.

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Makrocykle fenolowo-formaldehydowe w układach polimerowych. Cz. 1. Otrzymywanie z wykorzystaniem polireakcji łańcuchowych i w wyniku immobilizowania na matrycy polimerowej

Parzuchowski P., Rokicki G.

Polimery

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2000

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T. 45, nr 4

225-236

PL

Przedstawiono przegląd literatury dotyczący syntezy, właściwości i zastosowania polimerów zawierających wbudowane makrocykle fenolowo-formaldehydowe, ze szczególnym uwzględnieniem metod ich przyłączania do łańcuchów polimerowych.

EN

A review with 39 references covering synthesis, properties and uses of polymers containing in-built phenol-formaldehyde macrocycles with particular reference to the methods of bonding them to polymer chains.