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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.

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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.

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Pegylacja - metoda zmiany właściwości leków polipeptydowych, substancji biologicznie aktywnych

Ferenc J., Kieć-Kononowicz K.

Wiadomości Chemiczne

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2005

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[Z] 59, 11-12

953--979

EN

This review attempts to briefly summarize the recent developments in the area of PEGylation. Pegylation, the process by which polyethylene glycol chains are attached to as well protein and peptide drugs as low molecular weight molecules is used to modify the properties of drugs, biologically active structures. It has influence on pharmacokinetic and pharmacodynamic properties, stability and immunogenicity of structures. The advantages and drawbacks of such modifications were discussed. Pegylation of polypeptide and protein structures as well as small molecules was presented. Pegylation process was divided in two groups: pegylation of the first and second generation. Both processes were presented. Examples of pegylated drugs (Adagen, Oncaspar - first generation; PEG-intron, Pegasys, Somavert, Neulasta - second generation) already introduced into the market were shortly presented, structures being under investigation were mentioned.