OPEN Repository

Welcome to OPEN - the Repository of Open Scientific Publications, run by the Interdisciplinary Centre for Mathematical and Computational Modelling, University of Warsaw, previously operating as the CeON Repository. The Repository enables Polish researchers from all fields to openly share their articles, books, conference materials, reports, doctoral theses, and other scientific texts.

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22799 archived items

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Item
The Influence of Ligands on the Pd-Catalyzed Diarylation of Vinyl Esters
(MDPI, 2024) Brodzka, Anna; Koszelewski, Dominik; Trzeciak, Anna; Ruzik, Lena; Grela, Malgorzata; Ostaszewski, Ryszard; Institute of Organic Chemistry, Polish Academy of Sciences; Faculty of Chemistry, University of Wrocław; Faculty of Chemistry, Warsaw University of Technology
The impact of ligands on the palladium-catalyzed 1,2-diarylation reaction course is presented. The application of Pd-dmpzc as a catalyst provides an efficient, chemoselective and sustainable protocol for the synthesis of valuable 1,2-diphenylethyl acetates. The reaction is conducted in water under mild conditions. Reaction products can be easily separated from the reaction mixture and catalyst by simple extraction. What is more, the rational choice of catalyst significantly reduces the leaching of the metal into the product and its contamination (0.1 ppm). Efficient phase separation and ultralow Pd leaching enable the reuse of the water medium containing the Pd-dmpzc catalyst several times without a significant loss of activity and with even higher selectivity (from 95% to 100% in the third cycle). The recyclability of both the catalyst and the reaction medium together with high chemoselectivity and low palladium leaching reduces the amount of waste and the cost of the process, exhibiting an example of a sustainable and green methodology.
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Evaluation of Antibacterial Activity against Nosocomial Pathogens of an Enzymatically Derived α-Aminophosphonates Possessing Coumarin Scaffold
(MDPI, 2023) Kowalczyk, Paweł; Koszelewski, Dominik; Brodzka, Anna; Kramkowski, Karol; Ostaszewski, Ryszard; Holban, Alina-Maria; Institute of Organic Chemistry, Polish Academy of Sciences; Department of Animal Nutrition, The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences; Department of Physical Chemistry, Medical University of Bialystok
The purpose of the present study was to evaluate the synergistic effect of two important pharmacophores, coumarin and α-amino dimethyl phosphonate moieties, on antimicrobial activity against selected strains of multidrug-resistant nosocomial pathogenic bacteria. The previously developed enzyme-catalysed Kabachnik–Fields protocol allowed us to obtain the studied compounds with high yields which were free from metal impurities. The structure–activity relationship revealed that inhibitory activity is strongly related to the presence of the trifluoromethyl group (CF3−) in the coumarin scaffold. MIC and MBC studies carried out on six selected pathogenic bacterial strains (Gram-positive pathogenic Staphylococcus aureus (ATCC 23235) strain, as well as on Gram-negative Acinetobacter baumannii (ATCC 17978), Pseudomonas aeruginosa (ATCC 15442), Enterobacter cloacae (ATCC 49141), Porphyromonas gingivalis (ATCC 33277), and Treponema denticola (ATCC 35405)) have shown that tested compounds show a strong bactericidal effect at low concentrations. Among all agents investigated, five exhibit higher antimicrobial activity than those observed for commonly used antibiotics. It should be noted that all the compounds tested showed very high activity against S. aureus, which is the main source of nosocomial infections that cause numerous fatalities. Furthermore, we have shown that the studied coumarin-based α-aminophosphonates, depending on their structural characteristics, are non-selective and act efficiently against various Gram-positive and Gram-negative pathogens, which is of great importance for hospitalised patients.
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Enzymatic Synthesis of a Novel Coumarin Aminophosphonates: Antibacterial Effects and Oxidative Stress Modulation on Selected E. coli Strains
(MDPI, 2023) Koszelewski, Dominik; Kowalczyk, Paweł; Brodzka, Anna; Hrunyk, Anastasiia; Kramkowski, Karol; Ostaszewski, Ryszard; Fernández-García, Marta; Institute of Organic Chemistry, Polish Academy of Sciences; Department of Animal Nutrition, The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences; Department of Physical Chemistry, Medical University of Bialystok
The objective of the present study was to evaluate the synergistic effect of two important pharmacophores, coumarin and -amino dimethyl phosphonate moieties, on antimicrobial activity toward selected LPS-varied E. coli strains. Studied antimicrobial agents were prepared via a Kabachnik–Fields reaction promoted by lipases. The products were provided with an excellent yield (up to 92%) under mild, solvent- and metal-free conditions. A preliminary exploration of coumarin -amino dimethyl phosphonate analogs as novel antimicrobial agents was carried out to determine the basic features of the structure responsible for the observed biological activity. The structure–activity relationship revealed that an inhibitory activity of the synthesized compounds is strongly related to the type of the substituents located in the phenyl ring. The collected data demonstrated that coumarin-based -aminophosphonates can be potential antimicrobial drug candidates, which is particularly crucial due to the constantly increasing resistance of bacteria to commonly used antibiotics.
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Synthesis and Antimicrobial Activity of the Pathogenic E. coli Strains of p-Quinols: Additive Effects of Copper-Catalyzed Addition of Aryl Boronic Acid to Benzoquinones
(MDPI, 2023) Koszelewski, Dominik; Kowalczyk, Paweł; Samsonowicz-Górski, Jan; Hrunyk, Anastasiia; Brodzka, Anna; Łęcka, Justyna; Kramkowski, Karol; Ostaszewski, Ryszard; Hadjikakou, Sotiris K.; Institute of Organic Chemistry, Polish Academy of Sciences; Department of Animal Nutrition, The Kielanowski Institute of Animal Physiology and Nutrition, Polish Academy of Sciences; Department of Physical Chemistry, Medical University of Bialystok
A mild and efficient protocol for the synthesis of p-quinols under aqueous conditions was developed. The pivotal role of additives in the copper-catalyzed addition of aryl boronic and heteroaryl boronic acids to benzoquinones was observed. It was found that polyvinylpyrrolidone (PVP) was the most efficient additive used for the studied reaction. The noteworthy advantages of this procedure include its broad substrate scope, high yields up to 91%, atom economy, and usage of readily available starting materials. Another benefit of this method is the reusability of the catalytic system up to four times. Further, the obtained p-quinols were characterized on the basis of their antimicrobial activities against E. coli. Antimicrobial activity was further compared with the corresponding 4-benzoquinones and 4-hydroquinones. Among tested compounds, seven derivatives showed an antimicrobial activity profile similar to that observed for commonly used antibiotics such as ciprofloxacin, bleomycin, and cloxacillin. In addition, the obtained p-quinols constitute a suitable platform for further modifications, allowing for a convenient change in their biological activity profile.
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Simultaneous Enantiodivergent Synthesis of Diverse Lactones and Lactams via Sequential One-Pot Enzymatic Kinetic Resolution–Ring-Closing Metathesis Reactions
(MDPI, 2022) Brodzka, Anna; Koszelewski, Dominik; Ostaszewski, Ryszard; Khlebnikov, Alexander F.; Rostovskii, Nikolai V.; Institute of Organic Chemistry, Polish Academy of Sciences
One of the goals of diversity-oriented synthesis is to achieve the structural diversity of obtained compounds. As most biologically active compounds are chiral, it is important to develop enantioselective methods of their synthesis. The application of kinetic resolution in DOS is problematic because of low efficiency (max. 50% yield) and many purification steps. The further derivatization of kinetic resolution products in DOS leads to the formation of a narrow library of compounds of the same stereochemistry. To overcome these limitations, we present a new concept in which the kinetic resolution is combined, the subsequent reaction of which in a one-pot protocol leads to the simultaneous formation of two skeletally and enantiomerically diverse platform molecules for DOS. Their further derivatization can gain access to a double-sized library of products in respect to a classical approach. The validity of our concept was evidenced in enzymatic kinetic resolution followed by a ring-closing metathesis cascade. From racemic carboxylic acid ester, a simultaneous formation of enantiopure lactones and lactams was achieved. These compounds are important building blocks in organic and medicinal chemistry and until now were synthesized in separate procedures.