Can any Basic/Nucleophile Quaternary Salt Promote the Carbonatation of Epoxides? A Review.

This review examines the role of ionic liquids (ILs) in the catalytic carbonation of epoxides for the synthesis of cyclic carbonates, focusing on the key factors that influence reaction efficiency. The nucleophilicity and basicity of the anions in IL catalysts are highlighted as critical components for promoting the cycloaddition reaction with CO. The solubility and ionicity of the ILs also significantly affect the reaction, with higher ionicity leading to better solubilization and catalytic performance.

Solvents' and Reagents' Noninnocent Roles in the Groebke-Blackburn-Bienaymé (GBB) Multicomponent Reaction: Experimental and Computational Evidence.

Despite the frequent use of alcohols as solvents in GBB (Groebke-Blackburn-Bienaymé) protocols, the mechanistic reasons for their preference remain poorly understood. In this work, we combined experimental and theoretical investigations to elucidate the roles of solvents and reagents in the GBB reaction, revealing their noninnocent behavior. Kinetic experiments, high-resolution ESI-(+)-MS-(/MS), and DFT calculations demonstrated that methanol not only acts as a solvent but also as a cocatalyst, significantly influencing the reaction mechanism and accelerating key steps.

A Review on Luminescent Benzoselenadiazole Derivatives: Comparison with Benzothiadiazoles, Properties, Applications, and Trends.

This review comprehensively analyzes key parameters that govern the use of luminescent benzoselenadiazole (BSD) derivatives. We examine the main factors affecting their photophysical properties, including structural variations, heavy atom effects and environmental conditions, and discuss their potential applications in bioimaging technology. Whenever possible, the properties were compared to those of 2,1,3-benzoxadiazole and 2,1,3-benzothiadiazole analogues.

Integrating Machine Learning and SHAP Analysis to Advance the Rational Design of Benzothiadiazole Derivatives with Tailored Photophysical Properties.

2,1,3-Benzothiadiazole (BTD) derivatives show promise in advanced photophysical applications, but designing molecules with optimal desired properties remains challenging due to complex structure-property relationships. Existing computational methods have a high cost when predicting precise photophysical characteristics. Machine learning with Morgan fingerprints was employed to forecast BTD derivative maximum absorption and emission wavelengths.

Flavanone-enabled CuAAC Reaction: Noninnocent Reagents Driving a Mononuclear Mechanism Over the Dinuclear Paradigm.

In this work, we report the use of the CuAAC (copper-catalyzed azide-alkyne cycloaddition) reaction to obtain different triazole derivatives bridged to the naringenin skeleton, leading to the combination of a triazole pharmacophoric group with a bioactive flavanone. The generation of Cu(I) active species was done using CuSO salts and sodium ascorbate, resulting in moderate to high yields when the DMSO-water binary system was used as solvents. Mechanistic studies were done using density functional theory calculations and high-resolution mass spectrometry (HRMS).

Brazilian Student and Professor Mobility.

In this paper, we looked at the effect of mobility by students, post-doctorates and professors on science in Brazil. We analysed CAPES, CNPq, FAPESP and Incites data to examine the number of scholarships and their impact on posterior publishing. Decision trees, including the region of the country, length of stay by student and Professor, as well as institution abroad, were evaluated, along with logistic regressions.

Intragenic antimicrobial peptide Hs02 toxicity against leukemia cell lines is associated with increased expression of select pyroptotic components.

The anticancer potential of some antimicrobial peptides has been reported. Hs02 is a recently characterized Intragenic Antimicrobial Peptide (IAP), which was able to exhibit potent antimicrobial and anti-inflammatory action. In this study, we evaluate for the first time the antineoplastic potential of the Hs02 IAP using cell lines representing the main types of leukemia as cancer models.

Impact of Open Access Policy on Brazilian Science and Global Trends.

Open access (OA) publishing provides free online access to research articles without subscription fees. In Brazil, absence of financial support from academic institutions and limited government policies pose challenges to OA publication. Here, we used data from the Web of Science and Scopus to compare with global trends in journal accessibility and scientific quality metrics.

Revisiting Biginelli-like reactions: solvent effects, mechanisms, biological applications and correction of several literature reports.

This study critically reevaluates reported Biginelli-like reactions using a Kamlet-Abboud-Taft-based solvent effect model. Surprisingly, structural misassignments were discovered in certain multicomponent reactions, leading to the identification of pseudo three-component derivatives instead of the expected MCR adducts. Attempts to replicate literature conditions failed, prompting reconsideration of the described MCRs and proposed mechanisms.

Functional chromophores synthesized via multicomponent Reactions: A review on their use as cell-imaging probes.

This review aims to provide a comprehensive overview of recent advancements and applications of fluorescence imaging probes synthesized via MCRs (multicomponent reactions). These probes, also known as functional chromophores, belong to a currently investigated class of fluorophores that are presently being successfully applied in bioimaging experiments, especially in various living cell lineages. We describe some of the MCRs that have been employed in the synthesis of these probes and explore their applications in biological imaging, with an emphasis on cellular imaging.

Gel Biopolymer Electrolytes Based on Saline Water and Seaweed to Support the Large-Scale Production of Sustainable Supercapacitors.

Climate change and the demand for clean energy have challenged scientists worldwide to produce/store more energy to reduce carbon emissions. This work proposes a conductive gel biopolymer electrolyte to support the sustainable development of high-power aqueous supercapacitors. The gel uses saline water and seaweed as sustainable resources.

Sensitive hydrazine detection and quantification with a fluorescent benzothiadiazole sensor: selective lipid droplets and imaging.

In this work, we describe the design, synthesis, characterization, photophysical evaluation, DFT calculations, and application of two novel fluorescent benzothiadiazole (BTD) sensors for hydrazine detection and quantification at the cellular and multicellular () levels. The two probes were fully characterized, and their photophysical properties were evaluated. We tested the designed fluorogenic dye (named BTD-CHO) as a selective sensor for the rapid, sensitive, and selective detection of hydrazine.

In Melting Points We Trust: A Review on the Misguiding Characterization of Multicomponent Reactions Adducts and Intermediates.

We discuss herein the problems associated with using melting points to characterize multicomponent reactions' (MCRs) products and intermediates. Although surprising, it is not rare to find articles in which these MCRs final adducts (or their intermediates) are characterized solely by comparing melting points with those available from other reports. A brief survey among specialized articles highlights serious and obvious problems with this practice since, for instance, cases are found in which as many as 25 quite contrasting melting points have been attributed to the very same MCR adduct.

Correction: Exploratory comparisons between different anti-mitotics in clinically-used drug combination in triple negative breast cancer.

[This corrects the article DOI: 10.18632/oncotarget.28068.

Solvent Dependent Competitive Mechanisms for the Ugi Multicomponent Reaction: A Joint Theoretical and Experimental Study in the α-Acyl Aminocarboxamides vs α-Amino Amidines Formation.

A synthetic protocol for the preparation of α-acyl aminocarboxamides and α-amino amidines is proposed. The selectivity toward each of these two possible products was tuned by simple modifications of the reaction conditions. A broad scope is presented, allowing access to the desired products in up to 87% (Ugi adduct) and 93% (α-amino amidine).

Diverse 3-Methylthio-4-Substituted Maleimides through a Novel Rearrangement Reaction: Synthesis and Selective Cell Imaging.

A transition metal-free protocol for the preparation of fluorescent and non-fluoresent 3-methylthio-4-arylmaleimides in a single step through a new rearrangement from thiazolidine-2,4-diones is described. By employing the optimized reaction conditions, a broad scope of derivatives was prepared in ≤97% yield. The reaction tolerated several substituted aryl groups, including the challenging preparation of pyridyl-containing derivatives.

Catalytic Approaches to Multicomponent Reactions: A Critical Review and Perspectives on the Roles of Catalysis.

In this review, we comprehensively describe catalyzed multicomponent reactions (MCRs) and the multiple roles of catalysis combined with key parameters to perform these transformations. Besides improving yields and shortening reaction times, catalysis is vital to achieving greener protocols and to furthering the MCR field of research. Considering that MCRs typically have two or more possible reaction pathways to explain the transformation, catalysis is essential for selecting a reaction route and avoiding byproduct formation.

Fluorescent Benzothiadiazole Derivatives as Fluorescence Imaging Dyes: A Decade of New Generation Probes.

The current review describes advances in the use of fluorescent 2,1,3-benzothiadiazole (BTD) derivatives after nearly one decade since the first description of bioimaging experiments using this class of fluorogenic dyes. The review describes the use of BTD-containing fluorophores applied as, inter alia, bioprobes for imaging cell nuclei, mitochondria, lipid droplets, sensors, markers for proteins and related events, biological processes and activities, lysosomes, plasma membranes, multicellular models, and animals. A number of physicochemical and photophysical properties commonly observed for BTD fluorogenic structures are also described.

Exploratory comparisons between different anti-mitotics in clinically-used drug combination in triple negative breast cancer.

Triple-negative breast cancer (TNBC) constitutes a very aggressive type of breast cancer with few options of cytotoxic chemotherapy available for them. A chemotherapy regimen comprising of doxorubicin hydrochloride and cyclophosphamide, followed by paclitaxel, known as AC-T, is approved for usage as an adjuvant treatment for this type of breast cancer. In this study we aimed to elucidate the role of KIF11 in TNBC progression throughout its inhibition by two synthetic small molecules containing the DHPM core (dihydropyrimidin-2(1H)-ones or -thiones), with the hypothesis that these inhibitors could be an interesting option of antimitotic drug used alone or as adjuvant therapy in association with AC.

How and Why to Investigate Multicomponent Reactions Mechanisms? A Critical Review.

We review the most innovative efforts and greatest challenges faced when elucidating multicomponent reactions (MCRs) mechanisms. When compared to traditional reactions, the often two or more concurrent reactions pathways and the greater number of possible intermediates in MCRs turn their mechanistic investigation both a harder and trickier task. The common approaches used to investigate reaction mechanisms are often unable to clarify MCRs mechanisms; hence few but clever approaches are currently used to determine these mechanisms and to depict their key transformations.

From cow manure to bioactive carbon dots: a light-up probe for bioimaging investigations, glucose detection and potential immunotherapy agent for melanoma skin cancer.

Bioactive carbon dots (C-dots) with 4 nm were successfully produced with singular photophysical properties, low-toxicity and interesting immunological response. The optical properties of the C-dots were investigated and the "light-up" behaviour enabled them to be explored in glucose detection and bioimaging experiments (mitochondrial selective probe). C-dots were not selective to the tumour region and several fluorescent spots were visualized spread on animal bodies.

Reverse Semi-Combustion Driven by Titanium Dioxide-Ionic Liquid Hybrid Photocatalyst.

Unprecedented metal-free photocatalytic CO conversion to CO (up to 228±48 μmol g h) was displayed by TiO@IL hybrid photocatalysts prepared by simple impregnation of commercially available P25-titanium dioxide with imidazolium-based ionic liquids (ILs). The high activity of TiO@IL hybrid photocatalysts was mainly associated to (i) TiO@IL red shift compared to the pure TiO absorption, and thus a modification of the TiO surface electronic structure; (ii) TiO with IL bearing imidazolate anions lowered the CO activation energy barrier. The reaction mechanism was postulated to occur via CO photoreduction to formate species by the imidazole/imidazole radical redox pair, yielding CO and water.

Synthetic enzyme-catalyzed multicomponent reaction for Isoxazol-5(4)-one Syntheses, their properties and biological application; why should one study mechanisms?

In this work, we describe the application of a synthetic enzyme (synzyme) as the catalyst to promote the multicomponent synthesis of isoxazol-5(4H)-one derivatives. The catalytic system could be used up to 15 times without any notable loss of its activity. Some derivatives showed fluorescence and their photophysical data were evaluated.

Deciphering the Dynamics of Organic Nanoaggregates with AIEE Effect and Excited States: Lipophilic Benzothiadiazole Derivatives as Selective Cell Imaging Probes.

An aggregation-induced emission enhancement (AIEE) effect in fluorescent lipophilic 2,1,3-benzothiadiazole (BTD) derivatives and their organic nanoaggregates were studied. A set of techniques such as single-crystal X-ray, dynamic light scattering (DLS), electron paramagnetic resonance (EPR), UV-vis, fluorescence, and density functional theory (DFT) calculations have been used to decipher the formation/break (kinetics), properties, and dynamics of the organic nanoaggregates of three BTD small organic molecules. An in-depth study of the excited-state also revealed the preferential relaxation emissive pathways for the BTD derivatives and the dynamics associated with it.

Fluorescent Benzoselenadiazoles: Synthesis, Characterization, and Quantification of Intracellular Lipid Droplets and Multicellular Model Staining.

In this work, we described the synthesis of 10 new fluorescent 2,1,3-benzoselenadiazole small-molecule derivatives and their chemical- and photocharacterizations. The new derivatives could, for the first time, be successfully applied as selective live cell imaging probes (at nanomolar concentrations) and stained lipid-based structures preferentially. Density functional theory (DFT) calculations were used to help in understanding the photophysical data and the intramolecular charge-transfer (ICT) processes of the synthesized dyes.