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In Honor of the 80th Birthday of Professor Janusz Jurczak

A special issue of Molecules (ISSN 1420-3049). This special issue belongs to the section "Organic Chemistry".

Deadline for manuscript submissions: closed (31 December 2021) | Viewed by 47108

Special Issue Editors

Institute of Organic Chemistry, Polish Academy of Sciences, Warsaw, Poland
Interests: carbohydrates; cycloaddition reactions; solid-phase organic synthesis; stereoselective synthesis
Institute of Organic Chemistry, Polish Academy of Sciences, Warsaw, Poland
Interests: asymmetric synthesis; anion recognition; organocatalysis; receptors; supramolecular chemistry
Special Issues, Collections and Topics in MDPI journals
Institute of Organic Chemistry, Polish Academy of Sciences, Warsaw, Poland
Interests: asymmetric synthesis; conjugate addition; organocatalysis; phase-transfer catalysis

Special Issue Information

Dear Colleagues,

We would like to present this Special Issue of Molecules dedicated to Professor Janusz Jurczak. This Issue celebrates the 80th birthday of this outstanding researcher. Prof. Jurczak is an undisputed authority in the field of organic and supramolecular chemistry. In particular, he has been a pioneer of applications of a very high-pressure technique to organic synthesis, he has been involved in total syntheses of natural and biologically active compounds, using asymmetric catalysis and unconventional methodologies, and he has developed broad studies in molecular recognition including supramolecular processes and their chiral versions.

Prof. J. Jurczak is the author of over 500 research publications, numerous patents, and has a worldwide reputation as an outstanding scientist.

Prof. Jurczak was born in 1941 in Stryj, in today's western Ukraine, later his family moved to Warsaw. In 1964, he graduated from the Faculty of Chemistry at the Warsaw University of Technology. In 1970, he received his Ph.D. at the Institute of Organic Chemistry of the Polish Academy of Sciences under the supervision of Prof. Aleksander Zamojski. Then he started his postdoctoral fellowship at the group of Prof. Vladimir Prelog in ETH Zurich. In 1988, he received the title of professor. Professionally associated with the Institute of Organic Chemistry of the Polish Academy of Sciences and the Faculty of Chemistry at the University of Warsaw and, in both institutions he was promoted to full professor. Prof. Jurczak has shaped his research interests by collaborating with many outstanding representatives of organic chemistry, including Nobel laureates Prof. Vladimir Prelog and Prof. Jean-Marie Lehn. For his unquestionable contribution to the development of science, Prof. Janusz Jurczak was honored with numerous state and international scientific awards. He is also a laureate of an Honorary Doctorate of the University of Adam Mickiewicz in Poznań and the University of Warsaw. The scientific work of Prof. Jurczak is inextricably linked with educating generations of chemists – he has promoted 83 doctors, many of whom have already obtained the academic title of professor.

In his scientific work, he specializes in issues in the field of organic and supramolecular chemistry, including those related to synthesis, asymmetric catalysis, and unconventional methods of synthesis and supramolecular processes. The numerous scientific achievements of Professor Jurczak include innovative research, such as the introduction of high-pressure methods in organic chemistry.

 

Prof. Dr. Marek Chmielewski
Dr. Patryk Niedbala
Dr. Maciej Majdecki
Guest Editors

Manuscript Submission Information

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Keywords

  • Asymmetric catalysis
  • Cycloaddition reactions
  • Macrocyclic receptors
  • Molecular recognition
  • Organocatalysis
  • Stereochemistry
  • Stereocontrolled synthesis
  • Supramolecular chemistry

Published Papers (20 papers)

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Research

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17 pages, 8926 KiB  
Article
Preparation and Characterization of Indomethacin Supramolecular Systems with β-Cyclodextrin in Order to Estimate Photostability Improvement
by Marzena Jamrógiewicz and Marek Józefowicz
Molecules 2021, 26(24), 7436; https://0-doi-org.brum.beds.ac.uk/10.3390/molecules26247436 - 08 Dec 2021
Cited by 1 | Viewed by 2484
Abstract
Cyclodextrins have found wide application in contemporary chemistry, pharmacy and medicine. Because of their unique properties, cyclodextrins are constantly used in research on solubility or stability improvement, as well as other physicochemical properties of medicinal substances. Indomethacin (IND) is a photolabile molecule that [...] Read more.
Cyclodextrins have found wide application in contemporary chemistry, pharmacy and medicine. Because of their unique properties, cyclodextrins are constantly used in research on solubility or stability improvement, as well as other physicochemical properties of medicinal substances. Indomethacin (IND) is a photolabile molecule that also attracts the interest of researchers due to its therapeutic potential and the need to overcome its problematic photosensitivity. Supramolecular complexes of indomethacin with β-cyclodextrin (CD) are already known, and they show greater stability compared to complexes with other types of cyclodextrins. So far, however, the sensitivity to light of physical mixtures and inclusion complexes in the solid phase has not been studied, and their various stoichiometries have not yet been investigated. Due to this fact, the aim of the present study is to obtain supramolecular systems (inclusion complexes and physical mixtures) of indomethacin with three different amounts of β-cyclodextrin. Assessment of the photochemical stability of indomethacin-β-cyclodextrin systems in the solid state is performed in order to find the best correlation between IND stability and the amount of CD. Comparative analysis of physicochemical degradation for stoichiometry systems [CD:IND] = [1:1], [0.5:1] and [0.1:1] is performed by using ultraviolet spectroscopy, transmission—FTIR, reflection—ATR-FTIR infrared spectroscopy and DSC calorimetry. Full article
(This article belongs to the Special Issue In Honor of the 80th Birthday of Professor Janusz Jurczak)
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13 pages, 985 KiB  
Article
Efficacy of Selenourea Organocatalysts in Asymmetric Michael Reactions under Standard and Solvent-Free Conditions
by Mariola Zielińska-Błajet, Żaneta A. Mała and Rafał Kowalczyk
Molecules 2021, 26(23), 7303; https://0-doi-org.brum.beds.ac.uk/10.3390/molecules26237303 - 01 Dec 2021
Cited by 3 | Viewed by 1695
Abstract
By varying the steric and electronic surroundings of the hydrogen-bonding motif, the novel chiral Cinchona-alkaloid based selenoureas were developed. Acting as bifunctional catalysts, they were applied in the Michael reactions of dithiomalonate and nitrostyrene providing chiral adducts with up to 96% ee. [...] Read more.
By varying the steric and electronic surroundings of the hydrogen-bonding motif, the novel chiral Cinchona-alkaloid based selenoureas were developed. Acting as bifunctional catalysts, they were applied in the Michael reactions of dithiomalonate and nitrostyrene providing chiral adducts with up to 96% ee. The asymmetric Michael–-hemiacetalization reaction of benzylidene pyruvate and dimedone, performed with the assistance of 5 mol% of selenoureas, furnished the product with up to 93% ee and excellent yields. The effectiveness of the new hydrogen-bond donors was also proved in solvent-free reactions under ball mill conditions, supporting the sustainability of the devised catalytic protocol. Full article
(This article belongs to the Special Issue In Honor of the 80th Birthday of Professor Janusz Jurczak)
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14 pages, 3159 KiB  
Article
Adjusting the Structure of β-Cyclodextrin to Improve Complexation of Anthraquinone-Derived Drugs
by Agata Krzak, Olga Swiech, Maciej Majdecki, Piotr Garbacz, Paulina Gwardys and Renata Bilewicz
Molecules 2021, 26(23), 7205; https://0-doi-org.brum.beds.ac.uk/10.3390/molecules26237205 - 27 Nov 2021
Cited by 4 | Viewed by 2001
Abstract
β-Cyclodextrin (CD) derivatives containing an aromatic triazole ring were studied as potential carriers of the following drugs containing an anthraquinone moiety: anthraquinone-2-sulfonic acid (AQ2S); anthraquinone-2-carboxylic acid (AQ2CA); and a common anthracycline, daunorubicin (DNR). UV-Vis and voltammetry measurements were carried out to determine the [...] Read more.
β-Cyclodextrin (CD) derivatives containing an aromatic triazole ring were studied as potential carriers of the following drugs containing an anthraquinone moiety: anthraquinone-2-sulfonic acid (AQ2S); anthraquinone-2-carboxylic acid (AQ2CA); and a common anthracycline, daunorubicin (DNR). UV-Vis and voltammetry measurements were carried out to determine the solubilities and association constants of the complexes formed, and the results revealed the unique properties of the chosen CDs as effective pH-dependent drug complexing agents. The association constants of the drug complexes with the CDs containing a triazole and lipoic acid (βCDLip) or galactosamine (βCDGAL), were significantly larger than that of the native βCD. The AQ2CA and AQ2S drugs were poorly soluble, and their solubilities increased as a result of complex formation with βCDLip and βCDGAL ligands. AQ2CA and AQ2S are negatively charged at pH 7.4. Therefore, they were less prone to form an inclusion complex with the hydrophobic CD cavity than at pH 3 (characteristic of gastric juices) when protonated. The βCDTriazole and βCDGAL ligands were found to form weaker inclusion complexes with the positively charged drug DNR at an acidic pH (pH 5.5) than in a neutral medium (pH 7.4) in which the drug dissociates to its neutral, uncharged form. This pH dependence is favorable for antitumor applications. Full article
(This article belongs to the Special Issue In Honor of the 80th Birthday of Professor Janusz Jurczak)
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9 pages, 4569 KiB  
Article
Amplification of Electronic Circular Dichroism—A Tool to Follow Self-Assembly of Chiral Molecular Capsules
by Marek P. Szymański, Marcin Grajda and Agnieszka Szumna
Molecules 2021, 26(23), 7100; https://0-doi-org.brum.beds.ac.uk/10.3390/molecules26237100 - 24 Nov 2021
Cited by 2 | Viewed by 1632
Abstract
Electronic circular dichroism (ECD) can be used to study various aspects of self-assembly (definition of stoichiometric ratios, chirality amplification during self-assembly, host-guest complexation). In this work, we show that ECD is a valuable tool for monitoring the self-assembly of chiral peptide-based capsules. By [...] Read more.
Electronic circular dichroism (ECD) can be used to study various aspects of self-assembly (definition of stoichiometric ratios, chirality amplification during self-assembly, host-guest complexation). In this work, we show that ECD is a valuable tool for monitoring the self-assembly of chiral peptide-based capsules. By analyzing the signs, intensities, and temperature dependences of ECD bands, the effects of the non-specific processes can be separated from the restriction of intramolecular motion (RIM) caused by discrete self-assembly. Analysis of experimental and theoretical ECD spectra show that the differences between assembled and non-assembled species originate from induction of inherently chiral conformation and restriction of conformational freedom that leads to amplification of ECD signals during self-assembly of discrete species. Full article
(This article belongs to the Special Issue In Honor of the 80th Birthday of Professor Janusz Jurczak)
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11 pages, 1712 KiB  
Article
Two Unexpected Temperature-Induced Supermolecular Isomers from Multi-Topic Carboxylic Acid: Hydrogen Bonding Layer or Helix Tube
by Chunyang Li, Chunhong Tan, Juan Zhou, Yan-Yong Lin and Xiao-Feng Wang
Molecules 2021, 26(22), 6938; https://0-doi-org.brum.beds.ac.uk/10.3390/molecules26226938 - 17 Nov 2021
Cited by 1 | Viewed by 1482
Abstract
Under ambient conditions or 160 °C, two supramolecular isomers, namely [(H4PTTA)(H2O)2(DMF)] and [(H4PTTA)(H2O)3]··Guest (1-L and 1-H, H4PTTA = N-phenyl-N′-phenyl bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxdiimide tetra-carboxylic acid, Guest = [...] Read more.
Under ambient conditions or 160 °C, two supramolecular isomers, namely [(H4PTTA)(H2O)2(DMF)] and [(H4PTTA)(H2O)3]··Guest (1-L and 1-H, H4PTTA = N-phenyl-N′-phenyl bicyclo[2.2.2]oct-7-ene-2,3,5,6-tetracarboxdiimide tetra-carboxylic acid, Guest = DMF and H2O), were obtained through the reaction of H4PTTA in a mixture of H2O and dimethylformamide. The single crystal structures reveal the temperature-dependent supramolecular isomerism derived from the torsion of semi-rigid of H4PTTA. The 1-L prepared at room temperature is a hydrogen bond based achiral layer, while the hydrothermal synthesized 1-H is isomer resulted in an H-bond-based chiral tubes-packed supramolecular framework. Full article
(This article belongs to the Special Issue In Honor of the 80th Birthday of Professor Janusz Jurczak)
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9 pages, 26308 KiB  
Communication
Hydrogen Bonding Directed Self-Assembly of a Binuclear Ag(I) Metallacycle into a 1D Supramolecular Polymer
by Anna Brzechwa-Chodzyńska, Mateusz Gołdyn, Anna Walczak, Jack M. Harrowfield and Artur R. Stefankiewicz
Molecules 2021, 26(18), 5719; https://0-doi-org.brum.beds.ac.uk/10.3390/molecules26185719 - 21 Sep 2021
Viewed by 1934
Abstract
An Ag(I) metallacycle obtained unexpectedly during the preparation of Pd(II) complexes of the bifunctional ligand 5-([2,2′-bipyridin]-5-yl)pyrimidine-2-amine (L) has been characterized using X-ray structure determination as a binuclear, metallacyclic species [Ag2L2](SbF6)2, where both the [...] Read more.
An Ag(I) metallacycle obtained unexpectedly during the preparation of Pd(II) complexes of the bifunctional ligand 5-([2,2′-bipyridin]-5-yl)pyrimidine-2-amine (L) has been characterized using X-ray structure determination as a binuclear, metallacyclic species [Ag2L2](SbF6)2, where both the bipyridine and pyrimidine-N donors of L are involved in coordination to the metal. The full coordination environment of the Ag(I) defines a case of highly irregular 4-coordination. In the crystal, the Ag-metallacycles assemble into one-dimensional supramolecular metalladynamers linked together by hydrogen-bonding interactions. Full article
(This article belongs to the Special Issue In Honor of the 80th Birthday of Professor Janusz Jurczak)
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16 pages, 1969 KiB  
Article
Selective Esterification of Phosphonic Acids
by Damian Trzepizur, Anna Brodzka, Dominik Koszelewski and Ryszard Ostaszewski
Molecules 2021, 26(18), 5637; https://0-doi-org.brum.beds.ac.uk/10.3390/molecules26185637 - 17 Sep 2021
Cited by 5 | Viewed by 3112
Abstract
Here, we report straightforward and selective synthetic procedures for mono- and diesterification of phosphonic acids. A series of alkoxy group donors were studied and triethyl orthoacetate was found to be the best reagent as well as a solvent for the performed transformations. An [...] Read more.
Here, we report straightforward and selective synthetic procedures for mono- and diesterification of phosphonic acids. A series of alkoxy group donors were studied and triethyl orthoacetate was found to be the best reagent as well as a solvent for the performed transformations. An important temperature effect on the reaction course was discovered. Depending on the reaction temperature, mono- or diethyl esters of phosphonic acid were obtained exclusively with decent yields. The substrate scope of the proposed methodology was verified on aromatic as well as aliphatic phosphonic acids. The designed method can be successfully applied for small- and large-scale experiments without significant loss of selectivity or reaction yield. Several devoted experiments were performed to give insight into the reaction mechanism. At 30 °C, monoesters are formed via an intermediate (1,1-diethoxyethyl ester of phosphonic acid). At higher temperatures, similar intermediate forms give diesters or stable and detectable pyrophosphonates which were also consumed to give diesters. 31P NMR spectroscopy was used to assign the structure of pyrophosphonate as well as to monitor the reaction course. No need for additional reagents and good accessibility and straightforward purification are the important aspects of the developed protocols. Full article
(This article belongs to the Special Issue In Honor of the 80th Birthday of Professor Janusz Jurczak)
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9 pages, 1567 KiB  
Article
A Convenient Approach towards the Synthesis of ADMDP Type Iminosugars and Nojirimycin Derivatives from Sugar-Derived Lactams
by Piotr Szcześniak, Barbara Grzeszczyk and Bartłomiej Furman
Molecules 2021, 26(18), 5459; https://0-doi-org.brum.beds.ac.uk/10.3390/molecules26185459 - 08 Sep 2021
Viewed by 1886
Abstract
An efficient method for the synthesis of nojirimycin- and pyrrolidine-based iminosugar derivatives has been developed. The strategy is based on the partial reduction in sugar-derived lactams by Schwartz’s reagent and tandem stereoselective nucleophilic addition of cyanide or a silyl enol ether dictated by [...] Read more.
An efficient method for the synthesis of nojirimycin- and pyrrolidine-based iminosugar derivatives has been developed. The strategy is based on the partial reduction in sugar-derived lactams by Schwartz’s reagent and tandem stereoselective nucleophilic addition of cyanide or a silyl enol ether dictated by Woerpel’s or diffusion control models, which affords amino-modified iminosugars, such as ADMDP or higher nojirimycin derivatives. Full article
(This article belongs to the Special Issue In Honor of the 80th Birthday of Professor Janusz Jurczak)
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11 pages, 1721 KiB  
Article
Application of Polyamines and Amino Acid Derivatives Based on 2-Azabicycloalkane Backbone in Enantioselective Aldol Reaction
by Dominika Iwan, Karolina Kamińska and Elżbieta Wojaczyńska
Molecules 2021, 26(17), 5166; https://0-doi-org.brum.beds.ac.uk/10.3390/molecules26175166 - 26 Aug 2021
Cited by 2 | Viewed by 1694
Abstract
Carbon–carbon bond forming reactions, such as aldol reaction and condensation, belong to extremely desired transformations as manifested by >25,000 entries in SciFinder. Their stereoselective variant requires the use of an appropriate catalyst with a strictly defined structure. Hence, chiral 2-azabicycloalkane-based catalysts were designed, [...] Read more.
Carbon–carbon bond forming reactions, such as aldol reaction and condensation, belong to extremely desired transformations as manifested by >25,000 entries in SciFinder. Their stereoselective variant requires the use of an appropriate catalyst with a strictly defined structure. Hence, chiral 2-azabicycloalkane-based catalysts were designed, synthesized and tested in a stereoselective aldol reaction between cyclic/acyclic ketone and p-nitrobenzaldehyde both in organic and aqueous media. Among catalysts containing a chiral bicyclic backbone, amide based on 2-azabicyclo[3.2.1]octane and pyrrolidine units showed the best catalytic activity and afforded aldol product in excellent chemical yields (up to 95%) and good diastereo- and enantioselectivity (dr 22:78, ee up to 63%). Full article
(This article belongs to the Special Issue In Honor of the 80th Birthday of Professor Janusz Jurczak)
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10 pages, 1248 KiB  
Article
Asymmetric Dearomative (3+2)-Cycloaddition Involving Nitro-Substituted Benzoheteroarenes under H-Bonding Catalysis
by Maciej Saktura, Anna Skrzyńska, Sebastian Frankowski, Sylwia Wódka and Łukasz Albrecht
Molecules 2021, 26(16), 4992; https://0-doi-org.brum.beds.ac.uk/10.3390/molecules26164992 - 18 Aug 2021
Cited by 7 | Viewed by 2719
Abstract
In our studies, the organocatalytic 1,3-dipolar cycloaddition between 2-nitrobenzofurans or 2-nitrobenzothiophene and N-2,2,2-trifluoroethyl-substituted isatin imines has been developed. The reaction has been realized by employing bifunctional organocatalysis, with the use of squaramide derivative being crucial for the stereochemical efficiency of the process. [...] Read more.
In our studies, the organocatalytic 1,3-dipolar cycloaddition between 2-nitrobenzofurans or 2-nitrobenzothiophene and N-2,2,2-trifluoroethyl-substituted isatin imines has been developed. The reaction has been realized by employing bifunctional organocatalysis, with the use of squaramide derivative being crucial for the stereochemical efficiency of the process. The usefulness of the cycloadducts obtained has been confirmed in selected transformations, including aromative and non-aromative removal of the nitro group. Full article
(This article belongs to the Special Issue In Honor of the 80th Birthday of Professor Janusz Jurczak)
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14 pages, 3244 KiB  
Article
Towards Advances in Molecular Understanding of Boric Acid Biocatalyzed Ring-Opening (Co)Polymerization of δ-Valerolactone in the Presence of Ethylene Glycol as an Initiator
by Khadar Duale, Piotr Latos, Anna Chrobok, Adrian Domiński, Magdalena Martinka Maksymiak, Grażyna Adamus and Marek Kowalczuk
Molecules 2021, 26(16), 4859; https://0-doi-org.brum.beds.ac.uk/10.3390/molecules26164859 - 11 Aug 2021
Cited by 3 | Viewed by 2106
Abstract
Following our previous studies on the molecular level structure of (co)oligoesters obtained via anionic homo- and co-polymerization of novel β-substituted β-lactones, prepared by the atmospheric pressure carbonylation reaction of respective epoxides, the boric acid biocatalyzed ring-opening (co)polymerization of δ-valerolactone has been studied. As [...] Read more.
Following our previous studies on the molecular level structure of (co)oligoesters obtained via anionic homo- and co-polymerization of novel β-substituted β-lactones, prepared by the atmospheric pressure carbonylation reaction of respective epoxides, the boric acid biocatalyzed ring-opening (co)polymerization of δ-valerolactone has been studied. As a co-monomer the 6-methy-ε-caprolactone, prepared by the one-pot oxidation of respective alcohol, and ethylene glycol as polymerization initiator were used. The obtained copolymers were characterized by 1H-NMR, GPC and ESI-MS, respectively in order to confirm their chemical structures and identity. Subsequently, tandem mass spectrometry (MS-MS studies) via collision-induced dissociation were utilized to characterize the fragmentation pattern. ESI-MS and NMR analyses confirmed the formation of random linear copolymer chains composed of different polyester repeat units. MS-MS experiments showed that fragmentation proceeds via ester bound cleavage along the (co)polyester chains. The innovative aspect of this contribution is related to the elaboration of the telechelic (co)polymers end-capped with hydroxyl end groups and well-defined molecular architectures, which could facilitate the development of new flexible macromolecular systems for potential biomedical applications. Full article
(This article belongs to the Special Issue In Honor of the 80th Birthday of Professor Janusz Jurczak)
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16 pages, 2325 KiB  
Article
The Synthesis and Photophysical Properties of Weakly Coupled Diketopyrrolopyrroles
by Michał Pieczykolan, James B. Derr, Amara Chrayteh, Beata Koszarna, John A. Clark, Olena Vakuliuk, Denis Jacquemin, Valentine I. Vullev and Daniel T. Gryko
Molecules 2021, 26(16), 4744; https://0-doi-org.brum.beds.ac.uk/10.3390/molecules26164744 - 05 Aug 2021
Cited by 1 | Viewed by 2232
Abstract
Three centrosymmetric diketopyrrolopyrroles possessing either two 2-(2′-methoxyphenyl)benzothiazole or two 2-(2′-methoxyphenyl)benzoxazolo-thiophene scaffolds were synthesized in a straightforward manner, and their photophysical properties were investigated. Their emission was significantly bathochromically shifted as compared with that of simple DPPs reaching 650 nm. Judging from theoretical calculations [...] Read more.
Three centrosymmetric diketopyrrolopyrroles possessing either two 2-(2′-methoxyphenyl)benzothiazole or two 2-(2′-methoxyphenyl)benzoxazolo-thiophene scaffolds were synthesized in a straightforward manner, and their photophysical properties were investigated. Their emission was significantly bathochromically shifted as compared with that of simple DPPs reaching 650 nm. Judging from theoretical calculations performed with time-dependent density functional theory, in all three cases the excited state was localized on the DPP core and there was no significant CT character. Consequently, emission was almost independent of solvents’ polarity. DPPs possessing 2,5-thiophene units vicinal to DPP core play a role in electronic transitions, resulting in bathochromically shifted absorption and emission. Interestingly, as judged from transient absorption dynamics, intersystem crossing was responsible for the deactivation of the excited states of DPPs possessing para linkers but not in the case of dye bearing meta linker. Full article
(This article belongs to the Special Issue In Honor of the 80th Birthday of Professor Janusz Jurczak)
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15 pages, 5169 KiB  
Article
Attachment of Single-Stranded DNA to Certain SERS-Active Gold and Silver Substrates: Selected Practical Tips
by Edyta Pyrak, Kacper Jędrzejewski, Aleksandra Szaniawska and Andrzej Kudelski
Molecules 2021, 26(14), 4246; https://0-doi-org.brum.beds.ac.uk/10.3390/molecules26144246 - 13 Jul 2021
Cited by 4 | Viewed by 2256
Abstract
Layers formed from single-stranded DNA on nanostructured plasmonic metals can be applied as “working elements” in surface–enhanced Raman scattering (SERS) sensors used to sensitively and accurately identify specific DNA fragments in various biological samples (for example, in samples of blood). Therefore, the proper [...] Read more.
Layers formed from single-stranded DNA on nanostructured plasmonic metals can be applied as “working elements” in surface–enhanced Raman scattering (SERS) sensors used to sensitively and accurately identify specific DNA fragments in various biological samples (for example, in samples of blood). Therefore, the proper formation of the desired DNA layers on SERS substrates is of great practical importance, and many research groups are working to improve the process in forming such structures. In this work, we propose two modifications of a standard method used for depositing DNA with an attached linking thiol moiety on certain SERS-active structures; the modifications yield DNA layers that generate a stronger SERS signal. We propose: (i) freezing the sample when forming DNA layers on the nanoparticles, and (ii) when forming DNA layers on SERS-active macroscopic silver substrates, using ω-substituted alkanethiols with very short alkane chains (such as cysteamine or mercaptopropionic acid) to backfill the empty spaces on the metal surface unoccupied by DNA. When 6-mercapto-1-hexanol is used to fill the unoccupied places on a silver surface (as in experiments on standard gold substrates), a quick detachment of chemisorbed DNA from the silver surface is observed. Whereas, using ω-substituted alkanethiols with a shorter alkane chain makes it possible to easily form mixed DNA/backfilling thiol monolayers. Probably, the significantly lower desorption rate of the thiolated DNA induced by alkanethiols with shorter chains is due to the lower stabilization energy in monolayers formed from such compounds. Full article
(This article belongs to the Special Issue In Honor of the 80th Birthday of Professor Janusz Jurczak)
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11 pages, 2927 KiB  
Article
New Nitrogen, Sulfur-, and Selenium-Donating Ligands Derived from Chiral Pyridine Amino Alcohols. Synthesis and Catalytic Activity in Asymmetric Allylic Alkylation
by Marzena Wosińska-Hrydczuk and Jacek Skarżewski
Molecules 2021, 26(12), 3493; https://0-doi-org.brum.beds.ac.uk/10.3390/molecules26123493 - 08 Jun 2021
Cited by 5 | Viewed by 2133
Abstract
Although many chiral ligands for asymmetric catalysis have been developed, there is still a need for new structures allowing the modular approach. Recently, easy synthesis of chiral pyridine-containing β-amino alcohols has been elaborated by opening respective epoxides with enantiomeric 1-phenylethylamine. This paper reports [...] Read more.
Although many chiral ligands for asymmetric catalysis have been developed, there is still a need for new structures allowing the modular approach. Recently, easy synthesis of chiral pyridine-containing β-amino alcohols has been elaborated by opening respective epoxides with enantiomeric 1-phenylethylamine. This paper reports the synthetic transformation of β-amino alcohols into the new complexing pyridine-containing seleno- and thioethers. The amino alcohols were effectively converted to cyclic sulfonamidates, which were reacted with thiolates or phenyl selenide nucleophile. The reaction was diastereoselective, and its outcome depended on the configuration at the substitution center. The problem was discussed considering DFT optimized structures of both diastereomeric sulfonamidates. New amino-aldimine ligands were also synthesized from chiral pyridine-containing diamines. Nine new chiral ligands were tested in the Tsuji-Trost allylic alkylation resulting in the enantiomerically enriched product in up to 75% ee. The observed stereochemical induction agrees with the prevailing nucleophilic attack at the allylic carbon laying opposite to the complexing nitrogen of pyridine in η3-allylic intermediate complexes. Full article
(This article belongs to the Special Issue In Honor of the 80th Birthday of Professor Janusz Jurczak)
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16 pages, 3655 KiB  
Article
Carbazole-Based Colorimetric Anion Sensors
by Krystyna Maslowska-Jarzyna, Maria L. Korczak, Jakub A. Wagner and Michał J. Chmielewski
Molecules 2021, 26(11), 3205; https://0-doi-org.brum.beds.ac.uk/10.3390/molecules26113205 - 27 May 2021
Cited by 5 | Viewed by 3711
Abstract
Owing to their strong carbazole chromophore and fluorophore, as well as to their powerful and convergent hydrogen bond donors, 1,8-diaminocarbazoles are amongst the most attractive and synthetically versatile building blocks for the construction of anion receptors, sensors, and transporters. Aiming to develop carbazole-based [...] Read more.
Owing to their strong carbazole chromophore and fluorophore, as well as to their powerful and convergent hydrogen bond donors, 1,8-diaminocarbazoles are amongst the most attractive and synthetically versatile building blocks for the construction of anion receptors, sensors, and transporters. Aiming to develop carbazole-based colorimetric anion sensors, herein we describe the synthesis of 1,8-diaminocarbazoles substituted with strongly electron-withdrawing substituents, i.e., 3,6-dicyano and 3,6-dinitro. Both of these precursors were subsequently converted into model diamide receptors. Anion binding studies revealed that the new receptors exhibited significantly enhanced anion affinities, but also significantly increased acidities. We also found that rear substitution of 1,8-diamidocarbazole with two nitro groups shifted its absorption spectrum into the visible region and converted the receptor into a colorimetric anion sensor. The new sensor displayed vivid color and fluorescence changes upon addition of basic anions in wet dimethyl sulfoxide, but it was poorly selective; because of its enhanced acidity, the dominant receptor-anion interaction for most anions was proton transfer and, accordingly, similar changes in color were observed for all basic anions. The highly acidic and strongly binding receptors developed in this study may be applicable in organocatalysis or in pH-switchable anion transport through lipophilic membranes. Full article
(This article belongs to the Special Issue In Honor of the 80th Birthday of Professor Janusz Jurczak)
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14 pages, 2284 KiB  
Article
Tripodal, Squaramide-Based Ion Pair Receptor for Effective Extraction of Sulfate Salt
by Damian Jagleniec, Marcin Wilczek and Jan Romański
Molecules 2021, 26(9), 2751; https://0-doi-org.brum.beds.ac.uk/10.3390/molecules26092751 - 07 May 2021
Cited by 7 | Viewed by 2396
Abstract
Combining three features—the high affinity of squaramides toward anions, cooperation in ion pair binding and preorganization of the binding domains in the tripodal platform—led to the effective receptor 2. The lack of at least one of these key elements in the structures [...] Read more.
Combining three features—the high affinity of squaramides toward anions, cooperation in ion pair binding and preorganization of the binding domains in the tripodal platform—led to the effective receptor 2. The lack of at least one of these key elements in the structures of reference receptors 3 and 4 caused a lower affinity towards ion pairs. Receptor 2 was found to form an intramolecular network in wet chloroform, which changed into inorganic–organic associates after contact with ions and allowed salts to be extracted from an aqueous to an organic phase. The disparity in the binding mode of 2 with sulfates and with other monovalent anions led to the selective extraction of extremely hydrated sulfate anions in the presence of more lipophilic salts, thus overcoming the Hofmeister series. Full article
(This article belongs to the Special Issue In Honor of the 80th Birthday of Professor Janusz Jurczak)
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19 pages, 2019 KiB  
Article
Insight into the Sorption of 5-Fluorouracil and Methotrexate onto Soil–pH, Ionic Strength, and Co-Contaminant Influence
by Katarzyna Markiewicz, Anna Białk-Bielińska, Paulina Łukaszewicz, Piotr Stepnowski and Joanna Dołżonek
Molecules 2021, 26(6), 1674; https://0-doi-org.brum.beds.ac.uk/10.3390/molecules26061674 - 17 Mar 2021
Cited by 2 | Viewed by 1663
Abstract
Nowadays anticancer drugs (ADs), like other pharmaceuticals, are recognized as new emerging pollutants, meaning that they are not commonly monitored in the environment; however, they have great potential to enter the environment and cause adverse effects there. The current scientific literature highlights the [...] Read more.
Nowadays anticancer drugs (ADs), like other pharmaceuticals, are recognized as new emerging pollutants, meaning that they are not commonly monitored in the environment; however, they have great potential to enter the environment and cause adverse effects there. The current scientific literature highlights the problem of their presence in the aquatic environment by publishing more and more results on their analytics and ecotoxicological evaluation. In order to properly assess the risk associated with the presence of ADs in the environment, it is also necessary to investigate the processes that are important in understanding the environmental fate of these compounds. However, the state of knowledge on mobility of ADs in the environment is still very limited. Therefore, the main aim of our study was to investigate the sorption potential of two anticancer drugs, 5-fluorouracil (5-FU) and methotrexate (MTX), onto different soils. Special attention was paid to the determination of the influence of pH and ionic strength as well as presence of co-contaminants (cadmium (Cd2+) and another pharmaceutical—metoprolol (MET)) on the sorption of 5-FU and MTX onto soil. The obtained distribution coefficient values (Kd) ranged from 2.52 to 6.36 L·kg−1 and from 6.79 to 12.94 L·kg−1 for 5-FU and MTX, respectively. Investigated compounds may be classified as slightly or low mobile in the soil matrix (depending on soil). 5-FU may be recognized as more mobile in comparison to MET. It was proved that presence of other soil contaminants may strongly influence their mobility in soil structures. The investigated co-contaminant (MET) caused around 25-fold increased sorption of 5-FU, whereas diminished sorption of MTX. Moreover, the influence of environmental conditions such as pH and ionic strength on their sorption has been clearly demonstrated. Full article
(This article belongs to the Special Issue In Honor of the 80th Birthday of Professor Janusz Jurczak)
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Review

Jump to: Research

31 pages, 13454 KiB  
Review
Recent Advances in the Synthesis and Applications of Nitrogen-Containing Macrocycles
by Jakub Grajewski
Molecules 2022, 27(3), 1004; https://0-doi-org.brum.beds.ac.uk/10.3390/molecules27031004 - 02 Feb 2022
Cited by 14 | Viewed by 2800
Abstract
Macrocyclic nitrogen-containing compounds are versatile molecules. Supramolecular, noncovalent interactions of these macrocycles with guest molecules enables them to act as catalysts, fluorescent sensors, chiral or nonchiral selectors, or receptors of small molecules. In the solid state, they often display a propensity to form [...] Read more.
Macrocyclic nitrogen-containing compounds are versatile molecules. Supramolecular, noncovalent interactions of these macrocycles with guest molecules enables them to act as catalysts, fluorescent sensors, chiral or nonchiral selectors, or receptors of small molecules. In the solid state, they often display a propensity to form inclusion compounds. All of these properties are usually closely connected with the presence of nitrogen atoms in the macrocyclic ring. As most of the reviews published so far on macrocycles were written from the viewpoint of functional groups, synthetic methods, or the structure, search methods for literature reports in terms of the physicochemical properties of these compounds may be unobvious. In this minireview, the emphasis was put on the synthesis and applications of nitrogen-containing macrocyclic compounds, as they differ from their acyclic analogs, and at the same time are the driving force for further research. Full article
(This article belongs to the Special Issue In Honor of the 80th Birthday of Professor Janusz Jurczak)
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19 pages, 13353 KiB  
Review
Enhancement of Activity and Development of Low Pt Content Electrocatalysts for Oxygen Reduction Reaction in Acid Media
by Aldona Kostuch, Iwona A. Rutkowska, Beata Dembinska, Anna Wadas, Enrico Negro, Keti Vezzù, Vito Di Noto and Pawel J. Kulesza
Molecules 2021, 26(17), 5147; https://0-doi-org.brum.beds.ac.uk/10.3390/molecules26175147 - 25 Aug 2021
Cited by 10 | Viewed by 3220
Abstract
Platinum is a main catalyst for the electroreduction of oxygen, a reaction of primary importance to the technology of low-temperature fuel cells. Due to the high cost of platinum, there is a need to significantly lower its loadings at interfaces. However, then O [...] Read more.
Platinum is a main catalyst for the electroreduction of oxygen, a reaction of primary importance to the technology of low-temperature fuel cells. Due to the high cost of platinum, there is a need to significantly lower its loadings at interfaces. However, then O2-reduction often proceeds at a less positive potential, and produces higher amounts of undesirable H2O2-intermediate. Hybrid supports, which utilize metal oxides (e.g., CeO2, WO3, Ta2O5, Nb2O5, and ZrO2), stabilize Pt and carbon nanostructures and diminish their corrosion while exhibiting high activity toward the four-electron (most efficient) reduction in oxygen. Porosity of carbon supports facilitates dispersion and stability of Pt nanoparticles. Alternatively, the Pt-based bi- and multi-metallic catalysts, including PtM alloys or M-core/Pt-shell nanostructures, where M stands for certain transition metals (e.g., Au, Co, Cu, Ni, and Fe), can be considered. The catalytic efficiency depends on geometric (decrease in Pt–Pt bond distances) and electronic (increase in d-electron vacancy in Pt) factors, in addition to possible metal–support interactions and interfacial structural changes affecting adsorption and activation of O2-molecules. Despite the stabilization of carbons, doping with heteroatoms, such as sulfur, nitrogen, phosphorus, and boron results in the formation of catalytically active centers. Thus, the useful catalysts are likely to be multi-component and multi-functional. Full article
(This article belongs to the Special Issue In Honor of the 80th Birthday of Professor Janusz Jurczak)
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24 pages, 7672 KiB  
Review
High-Pressure Mechanistic Insight into Bioinorganic NO Chemistry
by Łukasz Orzeł, Maria Oszajca, Justyna Polaczek, Dominika Porębska, Rudi van Eldik and Grażyna Stochel
Molecules 2021, 26(16), 4947; https://0-doi-org.brum.beds.ac.uk/10.3390/molecules26164947 - 16 Aug 2021
Cited by 1 | Viewed by 1673
Abstract
Pressure is one of the most important parameters controlling the kinetics of chemical reactions. The ability to combine high-pressure techniques with time-resolved spectroscopy has provided a powerful tool in the study of reaction mechanisms. This review is focused on the supporting role of [...] Read more.
Pressure is one of the most important parameters controlling the kinetics of chemical reactions. The ability to combine high-pressure techniques with time-resolved spectroscopy has provided a powerful tool in the study of reaction mechanisms. This review is focused on the supporting role of high-pressure kinetic and spectroscopic methods in the exploration of nitric oxide bioinorganic chemistry. Nitric oxide and other reactive nitrogen species (RNS) are important biological mediators involved in both physiological and pathological processes. Understanding molecular mechanisms of their interactions with redox-active metal/non-metal centers in biological targets, such as cofactors, prosthetic groups, and proteins, is crucial for the improved therapy of various diseases. The present review is an attempt to demonstrate how the application of high-pressure kinetic and spectroscopic methods can add additional information, thus enabling the mechanistic interpretation of various NO bioinorganic reactions. Full article
(This article belongs to the Special Issue In Honor of the 80th Birthday of Professor Janusz Jurczak)
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