Synthesis of a -Tricarbonylrhenium(I) Complex with Pyrithione, Its Physicochemical Characterization, and Assessment of Biological Effects.

Research on rhenium complexes containing -tricarbonyl fragments has been on the rise in recent decades. Some complexes of this type exhibit advantageous properties that can be utilized in diagnostic and therapeutic applications. Herein, we report on the synthesis, structural characterization, solution speciation, and biological activity with mode of action studies of a new -tricarbonylrhenium-(I) complex with pyrithione ligand -[Re-(CO)(pyrithionato)-(benzonitrile)] ().

Phenanthrene Monomers and Dimers from with Antiproliferative Activity and Synergistic Effect with Doxorubicin Against Human Colon Cancer Cell Lines.

Continuing our search for bioactive compounds in species from the Juncaceae family, we investigated . The structures of five previously undescribed phenanthrenes-tenuins A-E (-)-and 14 known phenanthrenes (-), along with other components, were isolated and characterized using nuclear magnetic resonance and high-resolution mass spectrometry measurements. The antiproliferative activity of all of the isolated phenanthrenes was evaluated against the human colorectal adenocarcinoma cell lines COLO 205 (doxorubicin-sensitive) and COLO 320 (doxorubicin-resistant), as well as a non-tumorigenic human fibroblast cell line (CCD-19Lu), using the MTT viability assay.

Synthesis and Transformations of Bioactive Scaffolds via Modified Mannich and aza-Friedel-Crafts Reactions.

This account summarizes the synthesis of bifunctional glycine-type precursors substituted with 2- and 1-naphthol. The stabilization of precursors via partially aromatic ortho-quinone methide intermediate is tested with different cyclic imines in [4 + 2] cycloaddition. 8-Hydroxyquinoline is a biologically active moiety considered as a formal 1-naphthol analog, hence the behavior of the scaffold in Mannich reaction is examined.

Phenolic compounds from with biofilm-inhibitory activity against methicillin-resistant and strains.

Context: Antibiotic resistance in bacteria is a growing global problem, with biofilm formation and efflux pumps playing crucial roles in this issue.

Objective: This study explores the effects of phenolic compounds of against and methicillin-resistant (MRSA) strains by inhibiting biofilm formation and efflux pumps.

Materials And Methods: The methanolic extract of was fractionated guided by an antibiofilm assay, and the active fractions were analyzed by multistep chromatographic separation to yield five pure compounds.

Synthesis and Antimicrobial Evaluation of (+)-Neoisopulegol-Based Amino and Thiol Adducts.

A library of neoisopulegol-based amino and thiol adducts was developed from (+)-neoisopulegol, derived from commercially available (-)-isopulegol. Michael addition of different nucleophiles towards its highly active ,-unsaturated -lactone motif was accomplished, resulting in diverse amino and thiol analogs in stereoselective reactions. Then, the lactone ring was opened, with NH and benzylamine furnishing primary amide and -benzyl-substituted amide derivatives, respectively.

Decoding Lusichelins A-E: An In-Depth Look at the Metallophores of LEGE 07167-Structure, Production, and Functionality.

Essential trace metals are vital for cellular processes, such as respiration, DNA replication, and photosynthesis. Cyanobacteria must tightly regulate metal homeostasis to prevent deficiency or toxicity, yet their metallophores remain overlooked. Here, we report lusichelins A-E (-), new metallophores isolated from the marine cyanobacterium LEGE 07167.

Synthesis and Antiproliferative Effects of Grossheimin-Derived Aminoanalogues.

Grossheimin, a guaiane-type sesquiterpene lactone, displayed a diverse range of biological activities, including anticancer, anti-inflammatory and antimicrobial effects. Various amino analogues of grossheimin were prepared through a Michael addition at its highly active α-methylene-γ-lactone motif. On the other hand, grossheimin was reduced to diol, which was then subjected to nucleophilic addition or acetylation to introduce heteroatoms associated with oxygen, sulfur or nitrogen functionalities.

Synthesis, transformations and biological evaluation of 5‑chloro-8-hydroxyquinoline hybrids.

Taking in consideration of previous studies in the field of biological relevance and the chelating properties of derivatives bearing the hydroxyquinoline skeleton, establishing cationic centre by direct amidation as well as preparation compound with amino acid character was proposed. In order to test anticancer activity of the synthesised compounds, the applying of preliminary biological screening systems was planned. This concept is demonstrated in the context of the synthesis and transformation of a bifunctional glycine-type precursor substituted with 5‑chloro-8-hydroxyquinoline to hybrids with amino acid and amine feature.

Anticancer organometallic half-sandwich complexes of estrone-derived (N,N) donor ligands with enhanced aqueous solubility.

Four steroidal derivatives (L) bearing an (N,N) metal-chelating subunit on the D-ring, in addition to the organometallic [M(arene)(N,N)Cl]Cl complexes of L were synthesized and characterized, in which M(arene) is Rh(III)(η-CMe) or Ir(III)(η-CMe) or Ru(II)(η-p-cymene). The solution chemical properties of both the estrone-based ligands and selected complexes were investigated by spectroscopic methods. At pH = 7.

Bacteriophage Treatment Induces Phenotype Switching and Alters Antibiotic Resistance of ESBL .

Bacteriophage therapy represents a promising strategy to combat multidrug-resistant pathogens, such as . In this study, we explored the effects of a bacteriophage infection on an Extended Spectrum Beta-Lactamase (ESBL) positive isolate. We used next generation sequencing, proteomics and phenotypic screens to investigate the effect of bacteriophage infections on metabolism and resistance phenotypes.

Solution equilibrium and redox properties of metal complexes with 2-formylpyridine guanylhydrazone derivatives: Effect of morpholine and piperazine substitutions.

Schiff bases derived from aminoguanidine are extensively investigated for their structural versatility. The tridentate 2-formylpyridine guanylhydrazones act as analogues of 2-formyl or 2-acetylpyridine thiosemicarbazones, where the thioamide unit is replaced by the guanidyl group. Six derivatives of 2-formylpyridine guanylhydrazone were synthesized and their proton dissociation and complex formation processes with Cu(II), Fe(II) and Fe(III) ions were studied using pH-potentiometry, UV-visible, NMR and electron paramagnetic resonance spectroscopic methods.

Organometallic Half-Sandwich Complexes of 8-Hydroxyquinoline-Derived Mannich Bases with Enhanced Solubility: Targeting Multidrug Resistant Cancer.

Drug resistance is a major obstacle in cancer treatment. Herein, four novel organometallic complexes, with the general formula [Ru(η--cymene)(HL)Cl]Cl and [Rh(η-CMe)(HL)Cl]Cl, were developed to target multidrug-resistant (MDR) cancer cells, where HL denotes 8-hydroxyquinoline-derived Mannich bases (HQCl-pyr and HQCl-pip). The aim of the complexation was to obtain compounds with improved drug-like properties.

Selenocompounds as Potent Efflux Pump Inhibitors on Gram-positive Bacteria.

In recent years, selenocompounds have gained increasing attention as potential anticancer and antibacterial agents. Several selenoderivatives have been confirmed to act as MDR efflux pump inhibitors, based on their in vitro results against the bacterial AcrAB-TolC system and the cancer MDR efflux pump P-glycoprotein. Efflux pumps can contribute directly or indirectly to the virulence of bacteria, as they can reduce the intracellular concentration of antibacterial substances by expelling them out of the cell.

Synthesis of Tumor Selective Indole and 8-Hydroxyquinoline Skeleton Containing Di-, or Triarylmethanes with Improved Cytotoxic Activity.

The reaction between glycine-type aminonaphthol derivatives substituted with 2- or 1-naphthol and indole or 7-azaindole has been tested. Starting from 2-naphthol as a precursor, the reaction led to the formation of ring-closed products, while in the case of a 1-naphthol-type precursor, the desired biaryl ester was isolated. The synthesis of a bifunctional precursor starting from 5-chloro-8-hydroxyquinoline, morpholine, and ethyl glyoxylate via modified Mannich reaction is reported.

pH-Triggered Hydrogel Nanoparticles for Efficient Anticancer Drug Delivery and Bioimaging Applications.

In this work, we developed multifunctional hydrogel nanoparticles (NPs) that can encapsulate anticancer drugs and imaging contrast agents as well. Mitomycin C (MMC) and rhodamine B (RB) were selected as models for anticancer drugs and imaging contrasting agents, respectively. Both MMC and RB were linked to the succinated polyvinyl alcohol polymer (PVA-SA).

Impact of V9302, a Competitive Antagonist of Transmembrane Glutamine Flux on Reversal of Resistance in Breast Cancer Cell Lines.

Chemotherapy is a known treatment modality that improves the long-term survival of breast cancer patients. However, due to the resistance to numerous anticancer drugs, alternative chemotherapeutic strategies are required. Regarding antimetabolic drugs, several compounds have proven anticancer properties, such as statins.

Phytochemical Investigation of Schreb. and ACE-Inhibitory Activity of Oligomer Stilbenes of the Plant.

Phenolic compounds are the main special metabolites of Cyperaceae species from phytochemical, pharmacological, and chemotaxonomical points of view. The present study focused on the isolation, structure determination, and pharmacological investigation of constituents from . Twenty-six compounds, including lignans, stilbenes, flavonoids, megastigmanes, chromenes, and phenylpropanoids, were identified from the methanol extract of the plant.

Preparation of Dearomatized p-Coumaric Acid Derivatives as DNA Damage Response Inhibitors with Potent In Vitro Antitumor Effect.

Our research group previously identified graviquinone (1) as a promising antitumor metabolite that is formed in situ when the antioxidant methyl caffeate scavenges free radicals. Furthermore, it exerted a DNA damaging effect on cancer cells and a DNA protective effect on normal keratinocytes. To expand and explore chemical space around qraviquinone, in the current work we synthesized 9 new alkyl-substituted derivatives and tested their in vitro antitumor potential.

Leptochelins A-C, Cytotoxic Metallophores Produced by Geographically Dispersed Strains of Marine Cyanobacteria.

Metals are important cofactors in the metabolic processes of cyanobacteria, including photosynthesis, cellular respiration, DNA replication, and the biosynthesis of primary and secondary metabolites. In adaptation to the marine environment, cyanobacteria use metallophores to acquire trace metals when necessary as well as to reduce potential toxicity from excessive metal concentrations. Leptochelins A-C were identified as structurally novel metallophores from three geographically dispersed cyanobacteria of the genus .

Synthesis and Antibacterial Evaluation of Novel Small-Molecule Antibacterials of a Reduced Acridine Structure in Strains Including MRSA.

Background: The increasing antibacterial drug resistance remains a threat to global health with increasing mortality and morbidity. There is an urgent need to find novel antibacterials and develop alternative strategies to combat the increasing antibacterial drug resistance.

Objective: We aimed to synthesize novel small-molecule antibacterials to evaluate the structuredependent antibacterial compound activities against S.

Evaluation of Novel Benzo-annelated 1,4-dihydropyridines as MDR Modulators in Cancer Cells.

Background: Multidrug resistance (MDR) is the main problem in anticancer therapy today. Causative transmembrane efflux pumps in cancer cells have been reconsidered as promising anticancer target structures to restore anticancer drug sensitivity by various strategies, including MDR modulators. MDR modulators interfere with the efflux pumps and improve the cellular efficiency of chemotherapeutics.

Nitrogen-containing andrographolide derivatives with multidrug resistance reversal effects in cancer cells.

Multidrug resistance (MDR) remains a challenging issue in cancer treatment. Aiming at finding anticancer agents to overcome MDR, the triacetyl derivative (2) of the labdane diterpenoid lactone andrographolide (1) underwent the Michael-type addition reaction followed by elimination, yielding twenty-three new derivatives, bearing nitrogen-containing substituents (3-25). Their structures were assigned, mainly, by 1D and 2D NMR experiments.

[New minimally invasive treatment options in benign and malignant otorhinolaryngological diseases using nanostructured drug delivery systems].

Head and neck tumours are the 4th most common cancers in Hungary today. In terms of etiological factors, smoking and alcohol consumption are the leading ones. In the absence of these, HPV positivity counts as a causal factor.

Cyclic Amines Coupled to Indole Derivatives With Improved Efflux Pump Inhibiting Activity in Bacteria and Cancer Cells.

Background/aim: Indole skeleton has become a significant tool in the field of anticancer and antibacterial therapeutic strategies. The modified aza-Friedel-Crafts reaction by direct coupling of different cyclic imines and indole derivatives has been explored. To investigate the scope and limitations of the reaction and observe the effect of structural modifications, our aim was to resynthesize selected compounds as well as prepare new derivatives starting from 6,7-dimethoxy-3,4-dihydroisoquinoline, (4aR,8aR)-4a,5,6,7,8,8a-hexahydroquinoxalin-2(1H)-one and 7-azaindole.