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The Importance of Substituent Position for Antibacterial Activity in the Group of Thiosemicarbazide Derivatives
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Probing Non-Covalent Interactions through Molecular Balances: A REG-IQA Study
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Synthesis and Dynamic Behavior of Ce(IV) Double-Decker Complexes of Sterically Hindered Phthalocyanines
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Chemical-Vapor-Deposition-Synthesized Two-Dimensional Non-Stoichiometric Copper Selenide (β-Cu2−xSe) for Ultra-Fast Tetracycline Hydrochloride Degradation under Solar Light
Journal Description
Molecules
Molecules
is the leading international, peer-reviewed, open access journal of chemistry. Molecules is published semimonthly online by MDPI. The International Society of Nucleosides, Nucleotides & Nucleic Acids (IS3NA), the Spanish Society of Medicinal Chemistry (SEQT) and the International Society of Heterocyclic Chemistry (ISHC) are affiliated with Molecules and their members receive a discount on the article processing charges.
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- Rapid Publication: manuscripts are peer-reviewed and a first decision is provided to authors approximately 14.6 days after submission; acceptance to publication is undertaken in 2.7 days (median values for papers published in this journal in the second half of 2023).
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- Sections: published in 26 topical sections.
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- Companion journals for Molecules include: Foundations and Photochem.
Impact Factor:
4.2 (2023);
5-Year Impact Factor:
4.6 (2023)
Latest Articles
Hematene Nanoplatelets with Enhanced Visible Light Absorption; the Role of Aromatic Molecules
Molecules 2024, 29(13), 3115; https://doi.org/10.3390/molecules29133115 (registering DOI) - 29 Jun 2024
Abstract
Hematite has been considered an important candidate for the development of an efficient photoelectrocatalytic water-splitting system. One of the most serious obstacles that limits the efficiency of hematite is low absorption capacity in visible light. Herein, we report the production of hematene nanoplatelets
[...] Read more.
Hematite has been considered an important candidate for the development of an efficient photoelectrocatalytic water-splitting system. One of the most serious obstacles that limits the efficiency of hematite is low absorption capacity in visible light. Herein, we report the production of hematene nanoplatelets from hematite ore with yields of up to 60%, using a low-cost, sustainable method that is based on the ultrasonic treatment of hematite ore in a water solution of a series of organic aromatic compounds. We show that the chemisorption of molecules with increased aromaticity on the surface of hematene resulted in the significant improvement of its visible light absorptivity, with an increase of up to 200%. As a result, using a water solution of terephthalaldehyde as a liquid medium, hematite ore was exfoliated to hematene nanoplatelets with a yield of 40% and remarkable stability in water. Due to this, hematene was easily drop-casted on glass forming homogenous thin films with strong absorptivity in the visible region.
Full article
(This article belongs to the Section Materials Chemistry)
Open AccessArticle
Identification of Novel Isatin Derivative Bearing a Nitrofuran Moiety as Potent Multi-Isoform Aldehyde Dehydrogenase Inhibitor
by
Krishne Gowda, Asif Raza, Venugopal Vangala, Nazir Ahmad Lone, Jyh Ming Lin, Jaikee Kumar Singh, Sandeep Kumar Srivastava, Todd D. Schell, Gavin P. Robertson, Shantu Amin and Arun K. Sharma
Molecules 2024, 29(13), 3114; https://doi.org/10.3390/molecules29133114 (registering DOI) - 29 Jun 2024
Abstract
Aldehyde dehydrogenases (ALDHs) are a family of enzymes that aid in detoxification and are overexpressed in several different malignancies. There is a correlation between increased expression of ALDH and a poor prognosis, stemness, and resistance to several drugs. Several ALDH inhibitors have been
[...] Read more.
Aldehyde dehydrogenases (ALDHs) are a family of enzymes that aid in detoxification and are overexpressed in several different malignancies. There is a correlation between increased expression of ALDH and a poor prognosis, stemness, and resistance to several drugs. Several ALDH inhibitors have been generated due to the crucial role that ALDH plays in cancer stem cells. All of these inhibitors, however, are either ineffective, very toxic, or have yet to be subjected to rigorous testing on their effectiveness. Although various drug-like compounds targeting ALDH have been reported in the literature, none have made it to routine use in the oncology clinic. As a result, new potent, non-toxic, bioavailable, and therapeutically effective ALDH inhibitors are still needed. In this study, we designed and synthesized potent multi-ALDH isoform inhibitors based on the isatin and indazole pharmacophore. Molecular docking studies and enzymatic tests revealed that among all of the synthesized analogs, compound 3 is the most potent inhibitor of ALDH1A1, ALDH3A1, and ALDH1A3, exhibiting 51.32%, 51.87%, and 36.65% inhibition, respectively. The ALDEFLUOR assay further revealed that compound 3 acts as an ALDH broad spectrum inhibitor at 500 nM. Compound 3 was also the most cytotoxic to cancer cells, with an IC50 in the range of 2.1 to 3.8 µM for ovarian, colon, and pancreatic cancer cells, compared to normal and embryonic kidney cells (IC50 7.1 to 8.7 µM). Mechanistically, compound 3 increased ROS activity due to potent multi-ALDH isoform inhibition, which increased apoptosis. Taken together, this study identified a potent multi-isoform ALDH inhibitor that could be further developed as a cancer therapeutic.
Full article
(This article belongs to the Section Medicinal Chemistry)
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Open AccessArticle
Evaluation of the Effectiveness of Innovative Sorbents in Restoring Enzymatic Activity of Soil Contaminated with Bisphenol A (BPA)
by
Magdalena Zaborowska, Jadwiga Wyszkowska, Agata Borowik and Jan Kucharski
Molecules 2024, 29(13), 3113; https://doi.org/10.3390/molecules29133113 (registering DOI) - 29 Jun 2024
Abstract
As part of the multifaceted strategies developed to shape the common environmental policy, considerable attention is now being paid to assessing the degree of environmental degradation in soil under xenobiotic pressure. Bisphenol A (BPA) has only been marginally investigated in this ecosystem context.
[...] Read more.
As part of the multifaceted strategies developed to shape the common environmental policy, considerable attention is now being paid to assessing the degree of environmental degradation in soil under xenobiotic pressure. Bisphenol A (BPA) has only been marginally investigated in this ecosystem context. Therefore, research was carried out to determine the biochemical properties of soils contaminated with BPA at two levels of contamination: 500 mg and 1000 mg BPA kg−1 d.m. of soil. Reliable biochemical indicators of soil changes, whose activity was determined in the pot experiment conducted, were used: dehydrogenases, catalase, urease, acid phosphatase, alkaline phosphatase, arylsulfatase, and β-glucosidase. Using the definition of soil health as the ability to promote plant growth, the influence of BPA on the growth and development of Zea mays, a plant used for energy production, was also tested. As well as the biomass of aerial parts and roots, the leaf greenness index (SPAD) of Zea mays was also assessed. A key aspect of the research was to identify those of the six remediating substances—molecular sieve, zeolite, sepiolite, starch, grass compost, and fermented bark—whose use could become common practice in both environmental protection and agriculture. Exposure to BPA revealed the highest sensitivity of dehydrogenases, urease, and acid phosphatase and the lowest sensitivity of alkaline phosphatase and catalase to this phenolic compound. The enzyme response generated a reduction in the biochemical fertility index (BA21) of 64% (500 mg BPA) and 70% (1000 mg BPA kg−1 d.m. of soil). The toxicity of BPA led to a drastic reduction in root biomass and consequently in the aerial parts of Zea mays. Compost and molecular sieve proved to be the most effective in mitigating the negative effect of the xenobiotic on the parameters discussed. The results obtained are the first research step in the search for further substances with bioremediation potential against both soil and plants under BPA pressure.
Full article
(This article belongs to the Special Issue Efficient Chemical Technologies and Adsorbents for Environmental Pollution Removal and Wastes Recycling II)
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Open AccessCommunication
PhI(OAc)2-Promoted 1,2-Transfer Reaction between 1,1-Disubstituted Allylic Alcohols and Thiophenols
by
Guozhe Guo, Wenduo Li, **g**g Zheng, A** Liu, Qi Zhang and Yatao Wang
Molecules 2024, 29(13), 3112; https://doi.org/10.3390/molecules29133112 (registering DOI) - 29 Jun 2024
Abstract
The PhI(OAc)2-promoted 1,2-transfer reaction between allylic alcohols and thiophenols, conducted in an argon atmosphere, has proven to be effective in producing β-carbonyl sulfides from 1,1-disubstituted allylic alcohols in high yields. This method offers a fast and efficient way to synthesize β-carbonyl
[...] Read more.
The PhI(OAc)2-promoted 1,2-transfer reaction between allylic alcohols and thiophenols, conducted in an argon atmosphere, has proven to be effective in producing β-carbonyl sulfides from 1,1-disubstituted allylic alcohols in high yields. This method offers a fast and efficient way to synthesize β-carbonyl sulfides, which are valuable intermediates in organic synthesis. This discussion focuses on the effects of the oxidizer, temperature, and solvent on the reaction. A proposed tentative mechanism for this reaction is also discussed.
Full article
(This article belongs to the Special Issue Organic Synthesis and Application of Bioactive Molecules)
Open AccessArticle
Chitosan–Surfactant Composite Nanocoatings on Glass and Zinc Surfaces Prepared from Aqueous Solutions
by
Péter Márton, Liza Áder, Dávid Miklós Kemény, Adél Rácz, Dorina Kovács, Norbert Nagy, Gabriella Stefánia Szabó and Zoltán Hórvölgyi
Molecules 2024, 29(13), 3111; https://doi.org/10.3390/molecules29133111 (registering DOI) - 29 Jun 2024
Abstract
Hydrophobic coatings from chitosan–surfactant composites (ca. 400 nm thick by UV-Vis spectroscopy) for possible corrosion protection were developed on glass and zinc substrates. The surfactants (sodium dodecyl sulfate, SDS or sodium dodecylbenzenesulfonate, and SDBS) were added to the chitosan by two methods: mixing
[...] Read more.
Hydrophobic coatings from chitosan–surfactant composites (ca. 400 nm thick by UV-Vis spectroscopy) for possible corrosion protection were developed on glass and zinc substrates. The surfactants (sodium dodecyl sulfate, SDS or sodium dodecylbenzenesulfonate, and SDBS) were added to the chitosan by two methods: mixing the surfactants with the aqueous chitosan solutions before film deposition or impregnating the deposited chitosan films with surfactants from their aqueous solutions. For the mixed coatings, it was found that the lower surface tension of solutions (40–45 mN/m) corresponded to more hydrophobic (80–90°) coatings in every case. The hydrophobicity of the impregnated coatings was especially significant (88° for SDS and 100° for SDBS). Atomic force microscopy studies revealed a slight increase in roughness (max 1.005) for the most hydrophobic coatings. The accumulation of surfactants in the layer was only significant (0.8–1.0 sulfur atomic %) in the impregnated samples according to X-ray photoelectron spectroscopy. Polarization and electron impedance spectroscopy tests confirmed better barrier properties for these samples (40–50% pseudo-porosity instead of 94%). The degree of swelling in a water vapor atmosphere was significantly lower in the case of the impregnated coatings (ca. 25%) than that of the native ones (ca. 75%), measured by spectroscopic ellipsometry. Accordingly, good barrier layer properties require advantageous bulk properties in addition to surface hydrophobicity.
Full article
(This article belongs to the Special Issue Chitosan, Chitosan Derivatives, Polysaccharides and Their Applications—2nd Edition)
Open AccessReview
Physiological Mechanisms by Which the Functional Ingredients in Beer Impact Human Health
by
Yawen Zeng, Hafiz Ghulam Muhu-Din Ahmed, **a Li, Li’e Yang, **aoying Pu, **aomeng Yang, Tao Yang and Jiazhen Yang
Molecules 2024, 29(13), 3110; https://doi.org/10.3390/molecules29133110 (registering DOI) - 29 Jun 2024
Abstract
Nutritional therapy, for example through beer, is the best solution to human chronic diseases. In this article, we demonstrate the physiological mechanisms of the functional ingredients in beer with health-promoting effects, based on the PubMed, Google, CNKI, and ISI Web of Science databases,
[...] Read more.
Nutritional therapy, for example through beer, is the best solution to human chronic diseases. In this article, we demonstrate the physiological mechanisms of the functional ingredients in beer with health-promoting effects, based on the PubMed, Google, CNKI, and ISI Web of Science databases, published from 1997 to 2024. Beer, a complex of barley malt and hops, is rich in functional ingredients. The health effects of beer against 26 chronic diseases are highly similar to those of barley due to the physiological mechanisms of polyphenols (phenolic acids, flavonoids), melatonin, minerals, bitter acids, vitamins, and peptides. Functional beer with low purine and high active ingredients made from pure barley malt, as well as an additional functional food, represents an important development direction, specifically, ginger beer, ginseng beer, and coix-lily beer, as consumed by our ancestors ca. 9000 years ago. Low-purine beer can be produced via enzymatic and biological degradation and adsorption of purines, as well as dandelion addition. Therefore, this review paper not only reveals the physiological mechanisms of beer in overcoming chronic human diseases, but also provides a scientific basis for the development of functional beer with health-promoting effects.
Full article
Open AccessArticle
A Bicyclic Analog of the Linear Peptide Arodyn Is a Potent and Selective Kappa Opioid Receptor Antagonist
by
Solomon A. Gisemba, Michael J. Ferracane, Thomas F. Murray and Jane V. Aldrich
Molecules 2024, 29(13), 3109; https://doi.org/10.3390/molecules29133109 (registering DOI) - 29 Jun 2024
Abstract
Kappa opioid receptor (KOR) antagonists have potential therapeutic applications in the treatment of stress-induced relapse to substance abuse and mood disorders. The dynorphin A analog arodyn (Ac[Phe1,2,3,Arg4,D-Ala8]dynorphin A-(1–11)-NH2) exhibits potent and selective kappa opioid receptor
[...] Read more.
Kappa opioid receptor (KOR) antagonists have potential therapeutic applications in the treatment of stress-induced relapse to substance abuse and mood disorders. The dynorphin A analog arodyn (Ac[Phe1,2,3,Arg4,D-Ala8]dynorphin A-(1–11)-NH2) exhibits potent and selective kappa opioid receptor antagonism. Multiple cyclizations in longer peptides, such as dynorphin and its analogs, can extend the conformational constraint to additional regions of the peptide beyond what is typically constrained by a single cyclization. Here, we report the design, synthesis, and pharmacological evaluation of a bicyclic arodyn analog with two constraints in the opioid peptide sequence. The peptide, designed based on structure–activity relationships of monocyclic arodyn analogs, was synthesized by solid-phase peptide synthesis and cyclized by sequential ring-closing metathesis (RCM) in the C- and N-terminal sequences. Molecular modeling studies suggest similar interactions of key aromatic and basic residues in the bicyclic peptide with KOR as found in the cryoEM structure of KOR-bound dynorphin, despite substantial differences in the backbone conformations of the two peptides. The bicyclic peptide‘s affinities at KOR and mu opioid receptors (MOR) were determined in radioligand binding assays, and its KOR antagonism was determined in the [35S]GTPγS assay in KOR-expressing cells. The bicyclic analog retains KOR affinity and selectivity (Ki = 26 nM, 97-fold selectivity over MOR) similar to arodyn and exhibits potent KOR antagonism in the dynorphin-stimulated [35S]GTPγS assay. This bicyclic peptide represents a promising advance in preparing cyclic opioid peptide ligands and opens avenues for the rational design of additional bicyclic opioid peptide analogs.
Full article
(This article belongs to the Topic Opioids and Their Receptors: Present and Emerging Concepts in Opioid Drug Discovery)
Open AccessArticle
Construction of Fire Safe Thermoplastic Polyurethane/Reduced Graphene Oxide Hierarchical Composites with Electromagnetic Interference Shielding
by
Yan Liu, Ansheng Yao, Libi Fu, Shiwei **e, Yijie Zhang, Peihui Xu, Yuezhan Feng and Yongqian Shi
Molecules 2024, 29(13), 3108; https://doi.org/10.3390/molecules29133108 (registering DOI) - 29 Jun 2024
Abstract
Incorporating outstanding flame retardancy and electromagnetic interference shielding effectiveness (EMI SE) into polymers is a pressing requirement for practical utilization. In this study, we first employed the principles of microencapsulation and electrostatic interaction-driven self-assembly to encapsulate polyethyleneimine (PEI) molecules and Ti3C
[...] Read more.
Incorporating outstanding flame retardancy and electromagnetic interference shielding effectiveness (EMI SE) into polymers is a pressing requirement for practical utilization. In this study, we first employed the principles of microencapsulation and electrostatic interaction-driven self-assembly to encapsulate polyethyleneimine (PEI) molecules and Ti3C2Tx nanosheets on the surface of ammonium polyphosphate (APP), forming a double-layer-encapsulated structure of ammonium polyphosphate (APP@PEI@Ti3C2Tx). Subsequently, flame-retardant thermoplastic polyurethane (TPU) composites were fabricated by melting the flame-retardant agent with TPU. Afterwards, by using air-assisted thermocompression technology, we combined a reduced graphene oxide (rGO) film with flame-retardant TPU composites to fabricate hierarchical TPU/APP@PEI@Ti3C2Tx/rGO composites. We systematically studied the combustion behavior, flame retardancy, and smoke-suppression performance of these composite materials, as well as the flame-retardant mechanism of the expansion system. The results indicated a significant improvement in the interface interaction between APP@PEI@Ti3C2Tx and the TPU matrix. Compared to pure TPU, the TPU/10APP@PEI@1TC composite exhibited reductions of 84.1%, 43.2%, 62.4%, and 85.2% in peak heat release rate, total heat release, total smoke release, and total carbon dioxide yield, respectively. The averaged EMI SE of hierarchical TPU/5APP@PEI@1TC/rGO also reached 15.53 dB in the X-band.
Full article
Open AccessArticle
Electrocatalytic Properties of Quasi-2D Oxides LaSrMn0.5M0.5O4 (M = Co, Ni, Cu, and Zn) for Hydrogen and Oxygen Evolution Reactions
by
Kinithi M. K. Wickramaratne and Farshid Ramezanipour
Molecules 2024, 29(13), 3107; https://doi.org/10.3390/molecules29133107 (registering DOI) - 29 Jun 2024
Abstract
Designing cost-effective and highly efficient electrocatalysts for water splitting is a significant challenge. We have systematically investigated a series of quasi-2D oxides, LaSrMn0.5M0.5O4 (M = Co, Ni, Cu, Zn), to enhance the electrocatalytic properties of the two half-reactions
[...] Read more.
Designing cost-effective and highly efficient electrocatalysts for water splitting is a significant challenge. We have systematically investigated a series of quasi-2D oxides, LaSrMn0.5M0.5O4 (M = Co, Ni, Cu, Zn), to enhance the electrocatalytic properties of the two half-reactions of water-splitting, namely oxygen and hydrogen evolution reactions (OER and HER). The four materials are isostructural, as confirmed by Rietveld refinements with X-ray diffraction. The oxygen contents and metal valence states were determined by iodometric titrations and X-ray photoelectron spectroscopy. Electrical conductivity measurements in a wide range of temperatures revealed semiconducting behavior for all four materials. Electrocatalytic properties were studied for both half-reactions of water-splitting, namely, oxygen-evolution and hydrogen-evolution reactions (OER and HER). For the four materials, the trends in both OER and HER were the same, which also matched the trend in electrical conductivities. Among them, LaSrMn0.5Co0.5O4 showed the best bifunctional electrocatalytic activity for both OER and HER, which may be attributed to its higher electrical conductivity and favorable electron configuration.
Full article
(This article belongs to the Special Issue Exclusive Feature Papers in Inorganic Chemistry 2.0)
Open AccessArticle
Heteronuclear Complexes of Hg(II) and Zn(II) with Sodium Monensinate as a Ligand
by
Ivayla Pantcheva, Nikolay Petkov, Elzhana Encheva, Stiliyan Kolev, Svetlana Simova, Aleksandar Tsanev, Petar Dorkov and Angel Ugrinov
Molecules 2024, 29(13), 3106; https://doi.org/10.3390/molecules29133106 (registering DOI) - 29 Jun 2024
Abstract
The commercial veterinary antibiotic sodium monensinate (MonNa) binds mercury(II) or zinc(II) cations as thiocyanate [Hg(MonNa)2(SCN)2] (1) or isothiocyanate [Zn(MonNa)2(NCS)2] (2) neutral coordination compounds. The structure and physicochemical properties of 1 and
[...] Read more.
The commercial veterinary antibiotic sodium monensinate (MonNa) binds mercury(II) or zinc(II) cations as thiocyanate [Hg(MonNa)2(SCN)2] (1) or isothiocyanate [Zn(MonNa)2(NCS)2] (2) neutral coordination compounds. The structure and physicochemical properties of 1 and 2 were evaluated by the methods of single crystal and/or powder X-ray diffraction, infrared, nuclear magnetic resonance, X-ray photoelectron spectroscopies, and electrospray-mass spectrometry. The primary cores of the two complexes comprise HgS2O2 (1) and ZnN2O2 (2) coordination motifs, respectively, due to the ambidentate binding modes of the SCN–ligands. The directly bound oxygen atoms originate from the carboxylate function of the parent antibiotic. Sodium cations remain in the hydrophilic cavity of monensin and cannot be replaced by the competing divalent metal ions. Zinc(II) binding does not influence the monensin efficacy in the case of Bacillus cereus and Staphylococcus aureus whereas the antimicrobial assay reveals the potential of complex 2 as a therapeutic candidate for the treatment of infections caused by Bacillus subtilis, Kocuria rhizophila, and Staphylococcus saprophyticus.
Full article
(This article belongs to the Section Inorganic Chemistry)
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Open AccessReview
Polysaccharides from Porphyra haitanensis: A Review of Their Extraction, Modification, Structures, and Bioactivities
by
Minghao Sun, Yu** Zhang, Wuyou Gao, Yujia He, Yu Wang, Yan** Sun and Haixue Kuang
Molecules 2024, 29(13), 3105; https://doi.org/10.3390/molecules29133105 (registering DOI) - 29 Jun 2024
Abstract
Porphyra haitanensis (P. haitanensis), an important food source for coastal residents in China, has a long history of medicinal and edible value. P. haitanensis polysaccharides are some of the main active ingredients in P. haitanensis. It is worth noting that
[...] Read more.
Porphyra haitanensis (P. haitanensis), an important food source for coastal residents in China, has a long history of medicinal and edible value. P. haitanensis polysaccharides are some of the main active ingredients in P. haitanensis. It is worth noting that P. haitanensis polysaccharides have a surprising and satisfactory biological activity, which explains the various benefits of P. haitanensis to human health, such as anti-oxidation, immune regulation, anti-allergy, and anticancer properties. Hence, a systematic review aimed at comprehensively summarizing the recent research advances in P. haitanensis polysaccharides is necessary for promoting their better understanding. In this review, we systematically and comprehensively summarize the research progress on the extraction, purification, structural characterization, modification, and biological activity of P. haitanensis polysaccharides and address the shortcomings of the published research and suggest area of focus for future research, providing a new reference for the exploitation of polysaccharides from P. haitanensis in the fields of medicine and functional foods.
Full article
Open AccessArticle
Hypervalent Iodine-Catalyzed Fluorination of Diene-Containing Compounds: A Computational Study
by
Tianci Liu and Hai-Bei Li
Molecules 2024, 29(13), 3104; https://doi.org/10.3390/molecules29133104 (registering DOI) - 29 Jun 2024
Abstract
Studies have shown that the incorporation of fluorine into materials can improve their properties, but C–F bonds are not readily formed in nature. Although some researchers have studied the reaction of fluorinating alkenes catalyzed by hypervalent iodine, far too little attention has been
[...] Read more.
Studies have shown that the incorporation of fluorine into materials can improve their properties, but C–F bonds are not readily formed in nature. Although some researchers have studied the reaction of fluorinating alkenes catalyzed by hypervalent iodine, far too little attention has been paid to its reaction mechanism. This study aimed to explore the mechanism of the hypervalent iodine-catalyzed 1,4-difluorination of dienes. We found that the catalyst is favorable for the activation of C1=C2 double bonds through halogen bonds, and then two HFs interact with one F atom in the catalyst via hydrogen bonds, resulting in the cleavage of I–F bonds and the formation of [F–H∙∙∙F]−. Subsequently, the catalyst interacts with C1, and the roaming [F–H···F]− attacks C4 from the opposite side of the catalyst. After the fluorination step is completed, the nucleophile F− substitutes the catalyst via the SN2 mechanism. Our calculations demonstrated that the interaction between HF and F− is favorable for the stabilization of the transition state within the fluorination process for which the presence of two HFs in the reaction is the best. We also observed that [F–H∙∙∙F]− attacking C4 from the opposite side of the catalyst is more advantageous than attacking from the same side. This study therefore offers a novel perspective on the mechanism of the hypervalent iodine-catalyzed fluoridation of dienes.
Full article
(This article belongs to the Special Issue Mechanisms of Organic Reactions)
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Open AccessArticle
Solid Lipid Nanoparticles Encapsulating a Benzoxanthene Derivative in a Model of the Human Blood–Brain Barrier: Modulation of Angiogenic Parameters and Inflammation in Vascular Endothelial Growth Factor-Stimulated Angiogenesis
by
Giuliana Greco, Aleksandra Agafonova, Alessia Cosentino, Nunzio Cardullo, Vera Muccilli, Carmelo Puglia, Carmelina Daniela Anfuso, Maria Grazia Sarpietro and Gabriella Lupo
Molecules 2024, 29(13), 3103; https://doi.org/10.3390/molecules29133103 (registering DOI) - 28 Jun 2024
Abstract
Lignans, a class of secondary metabolites found in plants, along with their derivatives, exhibit diverse pharmacological activities, including antioxidant, antimicrobial, anti-inflammatory, and antiangiogenic ones. Angiogenesis, the formation of new blood vessels from pre-existing ones, is a crucial process for cancer growth and development.
[...] Read more.
Lignans, a class of secondary metabolites found in plants, along with their derivatives, exhibit diverse pharmacological activities, including antioxidant, antimicrobial, anti-inflammatory, and antiangiogenic ones. Angiogenesis, the formation of new blood vessels from pre-existing ones, is a crucial process for cancer growth and development. Several studies have elucidated the synergistic relationship between angiogenesis and inflammation in various inflammatory diseases, highlighting a correlation between inflammation and vascular endothelial growth factor (VEGF)-induced angiogenesis. Thus, the identification of novel molecules capable of modulating VEGF effects presents promising prospects for develo** therapies aimed at stabilizing, reversing, or even arresting disease progression. Lignans often suffer from low aqueous solubility and, for their use, encapsulation in a delivery system is needed. In this research, a bioinspired benzoxantene has been encapsulated in solid lipid nanoparticles that have been characterized for their pharmacotechnical properties and their thermotropic behavior. The effects of these encapsulated nanoparticles on angiogenic parameters and inflammation in VEGF-induced angiogenesis were evaluated using human brain microvascular endothelial cells (HBMECs) as a human blood–brain barrier model.
Full article
(This article belongs to the Special Issue Preparation, Characterization, and Effect of Lipid Nanoparticles Used in Different Application Fields IV)
Open AccessArticle
Synthesis and Evaluation of the First 68Ga-Labeled C-Terminal Hydroxamate-Derived Gastrin-Releasing Peptide Receptor-Targeted Tracers for Cancer Imaging with Positron Emission Tomography
by
Lei Wang, Hsiou-Ting Kuo, Chao-Cheng Chen, Devon Chapple, Nadine Colpo, Pauline Ng, Wing Sum Lau, Shireen Jozi, François Bénard and Kuo-Shyan Lin
Molecules 2024, 29(13), 3102; https://doi.org/10.3390/molecules29133102 (registering DOI) - 28 Jun 2024
Abstract
Gastrin-releasing peptide receptor (GRPR), overexpressed in many solid tumors, is a promising imaging marker and therapeutic target. Most reported GRPR-targeted radioligands contain a C-terminal amide. Based on the reported potent antagonist D-Phe-Gln-Trp-Ala-Val-Gly-His-Leu-NHOH, we synthesized C-terminal hydroxamate-derived [68Ga]Ga-LW02075 ([68
[...] Read more.
Gastrin-releasing peptide receptor (GRPR), overexpressed in many solid tumors, is a promising imaging marker and therapeutic target. Most reported GRPR-targeted radioligands contain a C-terminal amide. Based on the reported potent antagonist D-Phe-Gln-Trp-Ala-Val-Gly-His-Leu-NHOH, we synthesized C-terminal hydroxamate-derived [68Ga]Ga-LW02075 ([68Ga]Ga-DOTA-pABzA-DIG-D-Phe-Gln-Trp-Ala-Val-Gly-His-Leu-NHOH) and [68Ga]Ga-LW02050 ([68Ga]Ga-DOTA-Pip-D-Phe-Gln-Trp-Ala-Val-Gly-His-Leu-NHOH), and compared them with the closely related and clinically validated [68Ga]Ga-SB3 ([68Ga]Ga-DOTA-pABzA-DIG-D-Phe-Gln-Trp-Ala-Val-Gly-His-Leu-NHEt). Binding affinities (Ki) of Ga-SB3, Ga-LW02075, and Ga-LW02050 were 1.20 ± 0.31, 1.39 ± 0.54, and 8.53 ± 1.52 nM, respectively. Both Ga-LW02075 and Ga-LW02050 were confirmed to be GRPR antagonists by calcium release assay. Imaging studies showed that PC-3 prostate cancer tumor xenografts were clearly visualized at 1 h post injection by [68Ga]Ga-SB3 and [68Ga]Ga-LW02050 in PET images, but not by [68Ga]Ga-LW02075. Ex vivo biodistribution studies conducted at 1 h post injection showed that the tumor uptake of [68Ga]Ga-LW02050 was comparable to that of [68Ga]Ga-SB3 (5.38 ± 1.00 vs. 6.98 ± 1.36 %ID/g), followed by [68Ga]Ga-LW02075 (3.97 ± 1.71 %ID/g). [68Ga]Ga-SB3 had the highest pancreas uptake (37.3 ± 6.90 %ID/g) followed by [68Ga]Ga-LW02075 (17.8 ± 5.24 %ID/g), while the pancreas uptake of [68Ga]Ga-LW02050 was only 0.53 ± 0.11 %ID/g. Our data suggest that [68Ga]Ga-LW02050 is a promising PET tracer for detecting GRPR-expressing cancer lesions.
Full article
(This article belongs to the Special Issue New Advances in Radiopharmaceutical Sciences)
Open AccessArticle
Equilibrium Values for the Si-H Bond Length and Equilibrium Structures of Silyl Iodide and Halosilylenes
by
Jean Demaison and Jacques Liévin
Molecules 2024, 29(13), 3101; https://doi.org/10.3390/molecules29133101 (registering DOI) - 28 Jun 2024
Abstract
The equilibrium structures of silyl iodide, SiH3I, and silylene halides, SiHX (X = F, Cl, Br, I), were determined by using the mixed regression method, where approximate values of the rotational constants are supplemented by the structural parameters of a different
[...] Read more.
The equilibrium structures of silyl iodide, SiH3I, and silylene halides, SiHX (X = F, Cl, Br, I), were determined by using the mixed regression method, where approximate values of the rotational constants are supplemented by the structural parameters of a different origin. For this goal, it is shown that the r(Si-H) bond length can be determined by using the isolated SiH stretching frequency and that an accurate estimation of the bond angles is obtained by an MP2 calculation with a basis set of triple zeta quality. To check the accuracy of the experimental structures, they were also optimized by means of all electron CCSD(T) calculations using basis sets of quadruple zeta quality.
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(This article belongs to the Special Issue From Spectroscopic Insights to Structural Wonders: A Theme Issue Dedicated to Professor Jaan Laane)
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Open AccessArticle
Lattice Matching and Microstructure of the Aromatic Amide Fatty Acid Salts Nucleating Agent on the Crystallization Behavior of Recycled Polyethylene Terephthalate
by
Tianjiao Zhao, Fuhua Lin, Yapeng Dong, Meizhen Wang, Dingyi Ning, **nyu Hao, Jialiang Hao, Yanli Zhang, Dan Zhou, Yuying Zhao, Jun Luo, **gqiong Lu and Bo Wang
Molecules 2024, 29(13), 3100; https://doi.org/10.3390/molecules29133100 (registering DOI) - 28 Jun 2024
Abstract
To solve the decrease in the crystallization, mechanical and thermal properties of recycled polyethylene terephthalate (rPET) during mechanical recycling, the aromatic amide fatty acid salt nucleating agents Na-4-ClBeAmBe, Na-4-ClBeAmGl and Na-4-ClAcAmBe were synthesized and the rPET/nucleating agent blend was prepared by melting blending.
[...] Read more.
To solve the decrease in the crystallization, mechanical and thermal properties of recycled polyethylene terephthalate (rPET) during mechanical recycling, the aromatic amide fatty acid salt nucleating agents Na-4-ClBeAmBe, Na-4-ClBeAmGl and Na-4-ClAcAmBe were synthesized and the rPET/nucleating agent blend was prepared by melting blending. The molecular structure, the thermal stability, the microstructure and the crystal structure of the nucleating agent were characterized in detail. The differential scanning calorimetry (DSC) result indicated that the addition of the nucleating agent improved the crystallization temperature and accelerated the crystallization rate of the rPET. The nucleation efficiencies (NE) of the Na-4-ClBeAmBe, Na-4-ClBeAmGl and Na-4-ClAcAmBe were increased by 87.2%, 87.3% and 41.7% compared with rPET which indicated that Na-4-ClBeAmBe and Na-4-ClBeAmGl, with their long-strip microstructures, were more conducive to promoting the nucleation of rPET. The equilibrium melting points ( ) of rPET/Na-4-ClBeAmBe, rPET/Na-4-ClBeAmGl and rPET/Na-4-ClAcAmBe were increased by 11.7 °C, 18.6 °C and 1.9 °C compared with rPET, which illustrated that the lower mismatch rate between rPET and Na-4-ClBeAmGl (0.8% in b-axis) caused Na-4-ClBeAmGl to be the most capable in inducing the epitaxial crystallization and orient growth along the b-axis direction of the rPET. The small angle X-ray diffraction (SAXS) result proved this conclusion. Meanwhile, the addition of Na-4-ClBeAmGl caused the clearest increase in the rPET of its flexural strength and heat-distortion temperature (HDT) at 20.4% and 46.7%.
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(This article belongs to the Special Issue Molecular Insights into Soft Materials)
Open AccessArticle
Modified Halloysite as An Adsorbent for the Removal of Cu(II) Ions and Reactive Red 120 Dye from Aqueous Solutions
by
Krzysztof Kuśmierek, Andrzej Świątkowski, Ewa Wierzbicka and Izabella Legocka
Molecules 2024, 29(13), 3099; https://doi.org/10.3390/molecules29133099 (registering DOI) - 28 Jun 2024
Abstract
The adsorption of copper ions and Reactive Red 120 azo dye (RR-120) as models of water pollutants on unmodified halloysite (H-NM), as well as halloysites modified with sulfuric acid (H-SA) and (3-aminopropyl)triethoxysilane (H-APTES), was investigated. The results showed that adsorption of both the
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The adsorption of copper ions and Reactive Red 120 azo dye (RR-120) as models of water pollutants on unmodified halloysite (H-NM), as well as halloysites modified with sulfuric acid (H-SA) and (3-aminopropyl)triethoxysilane (H-APTES), was investigated. The results showed that adsorption of both the adsorbates was pH-dependent and increased with the increase in halloysite dosage. The adsorption kinetics were evaluated and the results demonstrated that the adsorption followed the pseudo-second-order model. The adsorption isotherms of Cu(II) ions and RR-120 dye on the halloysites were described satisfactorily by the Langmuir model. The maximum adsorption capacities for the Cu(II) ions were 0.169, 0.236, and 0.507 mmol/g, respectively, for H-NM, H-SA, and H-APTES indicating that the NH2-functionalization rather than the surface area of the adsorbents was responsible for the enhanced adsorption. The adsorption capacities for RR-120 dye were found to be 9.64 μmol/g for H-NM, 75.76 μmol/g for H-SA, and 29.33 μmol/g for H-APTES. The results demonstrated that APTES-functionalization and sulfuric acid activation are promising modifications, and both modified halloysites have good application potential for heavy metals as well as for azo dye removal.
Full article
(This article belongs to the Special Issue Efficient Chemical Technologies and Adsorbents for Environmental Pollution Removal and Wastes Recycling II)
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Open AccessArticle
Vanillic Acid Nanocomposite: Synthesis, Characterization Analysis, Antimicrobial, and Anticancer Potentials
by
Baskar Venkidasamy, Umadevi Subramanian, Hesham S. Almoallim, Sulaiman Ali Alharbi, Rahul Raj Chennam Lakshmikumar and Muthu Thiruvengadam
Molecules 2024, 29(13), 3098; https://doi.org/10.3390/molecules29133098 (registering DOI) - 28 Jun 2024
Abstract
Recently, nanoparticles have received considerable attention owing to their efficiency in overcoming the limitations of traditional chemotherapeutic drugs. In our study, we synthesized a vanillic acid nanocomposite using both chitosan and silver nanoparticles, tested its efficacy against lung cancer cells, and analyzed its
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Recently, nanoparticles have received considerable attention owing to their efficiency in overcoming the limitations of traditional chemotherapeutic drugs. In our study, we synthesized a vanillic acid nanocomposite using both chitosan and silver nanoparticles, tested its efficacy against lung cancer cells, and analyzed its antimicrobial effects. We used several characterization techniques such as ultraviolet–visible spectroscopy (UV-Vis), field emission scanning electron microscopy (FESEM), energy-dispersive X-ray spectroscopy (EDAX), thermogravimetric analysis (TGA), and differential scanning calorimetry (DSC) to determine the stability, morphological characteristics, and properties of the biosynthesized vanillic acid nanocomposites. Furthermore, the vanillic acid nanocomposites were tested for their antimicrobial effects against Escherichia coli and Staphylococcus aureus, and Candida albicans. The data showed that the nanocomposite effectively inhibited microbes, but its efficacy was less than that of the individual silver and chitosan nanoparticles. Moreover, the vanillic acid nanocomposite exhibited anticancer effects by increasing the expression of pro-apoptotic proteins (BAX, Casp3, Casp7, cyt C, and p53) and decreasing the gene expression of Bcl-2. Overall, vanillic acid nanocomposites possess promising potential against microbes, exhibit anticancer effects, and can be effectively used for treating diseases such as cancers and infectious diseases.
Full article
(This article belongs to the Special Issue Advances in Nanomaterials for Biomedical Applications)
Open AccessArticle
Inhibition of Monoamine Oxidases by Pyridazinobenzylpiperidine Derivatives
by
Jong Min Oh, Yaren Nur Zenni, Zeynep Özdemir, Sunil Kumar, Semanur Kılıç, Mevlüt Akdağ, Azime Berna Özçelik, Hoon Kim and Bijo Mathew
Molecules 2024, 29(13), 3097; https://doi.org/10.3390/molecules29133097 (registering DOI) - 28 Jun 2024
Abstract
Monoamine oxidase inhibitors (MAOIs) have been crucial in the search for anti-neurodegenerative medications and continued to be a vital source of molecular and mechanistic diversity. Therefore, the search for selective MAOIs is one of the main areas of current drug development. To increase
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Monoamine oxidase inhibitors (MAOIs) have been crucial in the search for anti-neurodegenerative medications and continued to be a vital source of molecular and mechanistic diversity. Therefore, the search for selective MAOIs is one of the main areas of current drug development. To increase the effectiveness and safety of treating Parkinson’s disease, new scaffolds for reversible MAO-B inhibitors are being developed. A total of 24 pyridazinobenzylpiperidine derivatives were synthesized and evaluated for MAO. Most of the compounds showed a higher inhibition of MAO-B than of MAO-A. Compound S5 most potently inhibited MAO-B with an IC50 value of 0.203 μM, followed by S16 (IC50 = 0.979 μM). In contrast, all compounds showed weak MAO-A inhibition. Among them, S15 most potently inhibited MAO-A with an IC50 value of 3.691 μM, followed by S5 (IC50 = 3.857 μM). Compound S5 had the highest selectivity index (SI) value of 19.04 for MAO-B compared with MAO-A. Compound S5 (3-Cl) showed greater MAO-B inhibition than the other derivatives with substituents of -Cl > -OCH3 > -F > -CN > -CH3 > -Br at the 3-position. However, the 2- and 4-position showed low MAO-B inhibition, except S16 (2-CN). In addition, compounds containing two or more substituents exhibited low MAO-B inhibition. In the kinetic study, the Ki values of S5 and S16 for MAO-B were 0.155 ± 0.050 and 0.721 ± 0.074 μM, respectively, with competitive reversible-type inhibition. Additionally, in the PAMPA, both lead compounds demonstrated blood–brain barrier penetration. Furthermore, stability was demonstrated by the 2V5Z-S5 complex by pi–pi stacking with Tyr398 and Tyr326. These results suggest that S5 and S16 are potent, reversible, selective MAO-B inhibitors that can be used as potential agents for the treatment of neurological disorders.
Full article
(This article belongs to the Special Issue Drug Design and Development for Dementia, Epilepsy, and Other Neurological Disorder Diseases)
Open AccessArticle
Optimizing Photoelectrochemical UV Imaging Photodetection: Construction of Anatase/Rutile Heterophase Homojunctions and Oxygen Vacancies Engineering in MOF-Derived TiO2
by
Yueying Ma, Yuewu Huang, Ju Huang, Zewu Xu, Yanbin Yang, Changmiao **e, Bingke Zhang, Guanghong Ao, Zhendong Fu, Aimin Li, Dongbo Wang and Liancheng Zhao
Molecules 2024, 29(13), 3096; https://doi.org/10.3390/molecules29133096 (registering DOI) - 28 Jun 2024
Abstract
Self-powered photoelectrochemical (PEC) ultraviolet photodetectors (UVPDs) are promising for next-generation energy-saving and highly integrated optoelectronic systems. Constructing a heterojunction is an effective strategy to increase the photodetection performance of PEC UVPDs because it can promote the separation and transfer of photogenerated carriers. However,
[...] Read more.
Self-powered photoelectrochemical (PEC) ultraviolet photodetectors (UVPDs) are promising for next-generation energy-saving and highly integrated optoelectronic systems. Constructing a heterojunction is an effective strategy to increase the photodetection performance of PEC UVPDs because it can promote the separation and transfer of photogenerated carriers. However, both crystal defects and lattice mismatch lead to deteriorated device performance. Here, we introduce a structural regulation strategy to prepare TiO2 anatase-rutile heterophase homojunctions (A-R HHs) with oxygen vacancies (OVs) photoanodes through an in situ topological transformation of titanium metal–organic framework (Ti-MOF) by pyrolysis treatment. The cooperative interaction between A-R HHs and OVs suppresses carrier recombination and accelerates carrier transport, thereby significantly enhancing the photodetection performance of PEC UVPDs. The obtained device realizes a high on/off ratio of 10,752, a remarkable responsivity of 24.15 mA W−1, an impressive detectivity of 3.28 × 1011 Jones, and excellent cycling stability. More importantly, under 365 nm light illumination, a high-resolution image of “HUST” (the abbreviation of Harbin University of Science and Technology) was obtained perfectly, confirming the excellent optical imaging capability of the device. This research not only presents an advanced methodology for constructing TiO2-based PEC UVPDs, but also provides strategic guidance for enhancing their performance and practical applications.
Full article
(This article belongs to the Special Issue Recent Progress in Nanomaterials in Electrochemistry)
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