jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Sivakamavalli Jeyachandran | Hethesh Chellapandian | Nemat Ali
Source: Biomimetics (article, 2023-11-01)
Field: Materials Science — Polymers and Plastics

Advancements in Composite Materials and Their Expanding Role in Biomedical Applications The synthesis of a Ni-doped ZnO nanocomposite incorporating chitosan (CS/Ni-doped ZnO) was achieved via a precipitation method, followed by annealing at 250 °C. This study comprehensively examined the nanocomposite's structural, functional, morphological, and porosity properties using various analytical techniques, including X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), high-resolution scanning electron microscopy (HR-SEM), transmission electron microscopy (TEM), and Brunauer-Emmett-Teller (BET) analysis. The presence of chitosan (CS) and nickel (Ni) within the nanocomposite, along with their influence on reducing the band gap of ZnO particles and enhancing the generation of electron-hole pairs, was confirmed using UV-visible near-infrared spectroscopy (UV-vis-NIR). The electrochemical properties of the CS/Ni-doped ZnO nanocomposite were investigated via electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) by utilizing a phosphate buffer solution with a pH of 6, which closely resembled the typical pH of bacterial cell walls. Finally, the prepared CS/Ni-doped ZnO nanocomposite was evaluated for its antibacterial and anticancer activities. The results demonstrated the highest inhibition of bacterial growth in <i>P. vulgaris</i>, whereas the lowest inhibition was found in <i>S. aureus</i> across various concentrations, thus highlighting its potential in antimicrobial applications. The cytotoxicity of CS/Ni-doped ZnO nanocomposites demonstrated remarkable effects with a half-maximum inhibitory concentration of approximately 80 ± 0.23 µg mL<sup>-1</sup> against MCF-7 breast cancer cell lines, following a dose-dependent manner. Nanocomposite ; Cyclic voltammetry ; Materials science ; Fourier transform infrared spectroscopy ; Dielectric spectroscopy ; Scanning electron microscope ; Nuclear chemistry ; Transmission electron microscopy ; High-resolution transmission electron microscopy ; Chemical engineering ; Analytical Chemistry (journal) ; Nanotechnology ; Electrochemistry ; Chemistry ; Composite material ; Organic chemistry ; Electrode Conducting polymers and applications ; Nanocomposite Films for Food Packaging ; Nanoparticles: synthesis and applications
Authors: Yan‐Cheng Liou | Yi‐Ru Chen | Ching‐Wen Hsu | X. HUANG | Heng‐Wei Wang | Wenwei Lin
Source: Advanced Synthesis & Catalysis (article, 2023-09-12)
Field: Chemistry — Organic Chemistry

Alkylidene Meldrum′s Acid as Acceptor‐Donor‐Acceptor with Azomethine Ylide for Organocatalytic Asymmetric (3+2) Cycloaddition/Annulation: Synthesis of Chromeno[4,3‐<i>b</i>]pyrrolidine Abstract A quinine‐derived thiourea‐catalyzed enantioselective double annulation strategy using alkylidene Meldrum′s acid as an acceptor‐donor‐acceptor with salicylaldehyde‐derived azomethine ylide is reported. The methodology is realized via a (3+2) cycloaddition/transesterification/decarboxylation sequence, giving chromeno[4,3‐ b ]pyrrolidines within 15–420 minutes at room temperature in 51–97% yields with 92–99% ee under 1–10 mol% catalyst loading. A plausible activation model is proposed for the excellent stereoinduction by H‐bond interaction between the catalyst and the Meldrum′s acid motif according to control experiments. Chemistry ; Annulation ; Cycloaddition ; Azomethine ylide ; Enantioselective synthesis ; Pyrrolidine ; Organocatalysis ; Ylide ; Catalysis ; Malononitrile ; Acceptor ; Meldrum's acid ; Decarboxylation ; Salicylaldehyde ; Medicinal chemistry ; Organic chemistry ; Stereochemistry ; Schiff base ; 1,3-Dipolar cycloaddition Asymmetric Synthesis and Catalysis ; Oxidative Organic Chemistry Reactions ; Synthesis and Catalytic Reactions
Authors: Ilya Lyagin | Nikolay Stepanov | D. Е. Presnov | А.С. Трифонов | Елена Ефременко
Source: International Journal of Molecular Sciences (article, 2023-01-17)
Field: Chemistry — Organic Chemistry

Self-Assembling Enzymatic Nanocomplexes with Polypeptides and Low-Weight Organic Compounds: Preparation, Characterization, and Application of New Antibacterials The self-assembling of nanosized materials is a promising field for research and development. Multiple approaches are applied to obtain inorganic, organic and composite nanomaterials with different functionality. In the present work, self-assembling nanocomplexes (NCs) were prepared on the basis of enzymes and polypeptides followed by the investigation of the influence of low-molecular weight biologically active compounds on the properties of the NCs. For that, the initially possible formation of catalytically active self-assembling NCs of four hydrolytic enzymes with nine effectors was screened via molecular modeling. It allowed the selection of two enzymes (hexahistidine-tagged organophosphorus hydrolase and penicillin acylase) and two compounds (emodin and naringenin) having biological activity. Further, such NCs based on surface-modified enzymes were characterized by a batch of physical and biochemical methods. At least three NCs containing emodin and enzyme (His<sub>6</sub>-OPH and/or penicillin acylase) have been shown to significantly improve the antibacterial activity of colistin and, to a lesser extent, polymyxin B towards both Gram-positive bacteria (<i>Bacillus subtilis</i>) and Gram-negative bacteria (<i>Escherichia coli</i>). Chemistry ; Enzyme ; Bacillus circulans ; Bacteria ; Escherichia coli ; Bacillus subtilis ; Combinatorial chemistry ; Hydrolysis ; Biochemistry ; Biology Click Chemistry and Applications ; Antimicrobial agents and applications ; Enzyme Catalysis and Immobilization
Authors: Hamad H. Al Mamari | J.P. Borel | Aobha Hickey | Eimear Courtney | Julia Merz | Xiaolei Zhang | Alexandra Friedrich | Todd B. Marder | Gerard P. McGlacken
Source: Chemistry - A European Journal (article, 2023-06-07)
Field: Chemistry — Organic Chemistry

Regioselective Iridium‐Catalyzed C8‐H Borylation of 4‐Quinolones via Transient <i>O</i>‐Borylated Quinolines The quinolone-quinoline tautomerization is harnessed to effect the regioselective C8-borylation of biologically important 4-quinolones by using [Ir(OMe)(cod)]<sub>2</sub> as the catalyst precursor, the silica-supported monodentate phosphine Si-SMAP as the ligand, and B<sub>2</sub> pin<sub>2</sub> as the boron source. Initially, O-borylation of the quinoline tautomer takes place. Critically, the newly formed 4-(pinBO)-quinolines then undergo N-directed selective Ir-catalyzed borylation at C8. Hydrolysis of the OBpin moiety on workup returns the system to the quinolone tautomer. The C8-borylated quinolines were converted to their corresponding potassium trifluoroborate (BF<sub>3</sub> K) salts and to their C8-chlorinated quinolone derivatives. The two-step C-H borylation-chlorination reaction sequence resulted in various C8-Cl quinolones in good yields. Conversion to C8-OH-, C8-NH<sub>2</sub> -, and C8-Ar-substituted quinolones was also feasible by using this methodology. Chemistry ; Borylation ; Tautomer ; Quinoline ; Regioselectivity ; Moiety ; Iridium ; Medicinal chemistry ; Catalysis ; Combinatorial chemistry ; Quinolone ; Stereochemistry ; Organic chemistry Catalytic C–H Functionalization Methods ; Organoboron and organosilicon chemistry ; Catalytic Cross-Coupling Reactions
Authors: Duncan W. Bruce
Source: Liquid Crystals (article, 2023-08-13)
Field: Chemistry — Organic Chemistry

Cyanobiphenyls and metallomesogens – where it started and where it went The author’s work in metallomesogens stemmed from initial preparations of κ1-complexes of cyanobiphenyls of the Group 10 metals, palladium and platinum. In this personalised account, these initial studies are described, put in the context of where the field was at that time and contextualised for the way the author’s own contributions to the field then developed. Context (archaeology) ; Liquid crystal ; Palladium ; Field (mathematics) ; Platinum ; Materials science ; Optics ; Organic chemistry ; Chemistry ; Physics ; Archaeology ; Mathematics ; Geography Organometallic Complex Synthesis and Catalysis ; Magnetism in coordination complexes ; Synthesis and Properties of Aromatic Compounds
Authors: Stepan K. Krymov | Diana I. Salnikova | Lyubov G. Dezhenkova | Fedor B. Bogdanov | Аlexander А. Korlyukov | Alexander M. Scherbakov | Andrey E. Shchekotikhin
Source: Pharmaceuticals (article, 2023-12-25)
Field: Chemistry — Organic Chemistry

Synthesis and Biological Evaluation of Chalconesulfonamides: En Route to Proapoptotic Agents with Antiestrogenic Potency Breast and other estrogen receptor α-positive cancers tend to develop resistance to existing drugs. Chalcone derivatives possess anticancer activity based on their ability to form covalent bonds with targets acting as Michael acceptors. This study aimed to evaluate the anticancer properties of a series of chalcones (<b>7a</b>-<b>l</b>) with a sulfonamide group attached to the vinyl ketone moiety. Chalconesulfonamides showed a potent antiproliferative effect at low micromolar concentrations against several cancer cell lines, including ERα-positive 4-hydroxytamoxifen-resistant MCF7/HT2. Immunoblotting of samples treated with the lead compound <b>7e</b> revealed its potent antiestrogenic activity (ERα/GREB1 axis) and induction of PARP cleavage (an apoptosis marker) in breast cancer cells. The obtained compounds represent a promising basis for further development of targeted drugs blocking hormone pathways in cancer cells. Chalcone ; Moiety ; Chemistry ; Estrogen receptor ; Potency ; Cancer research ; Pharmacology ; Apoptosis ; Sulfonamide ; Breast cancer ; Stereochemistry ; Cancer ; Medicine ; Biochemistry ; In vitro ; Internal medicine Synthesis and biological activity ; Genomics, phytochemicals, and oxidative stress ; Fungal Plant Pathogen Control
Authors: Ramil F. Fatykhov | Igor А. Khalymbadzha | Ainur D. Sharapov | Anastasia P. Potapova | Еkaterina S. Starnovskaya | Dmitry S. Kopchuk | Олег Н. Чупахин
Source: Chimica Techno Acta (article, 2023-04-11)
Field: Chemistry — Organic Chemistry

Expedient synthesis of 1,2,4-triazinyl substituted benzo[<i>c</i>]coumarins via double oxidation strategy Herein, we report a convenient one-pot synthesis of 1,2,4-triazinyl derivatives of benzocoumarins. The proposed approach consists in the nucleophilic addition of tetrahydrobenzo annulated dimethoxycoumarin to 1,2,4-triazines followed by double oxidation of both dihydrotriazine and tetrahydrobenzo groups with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ). The nucleophilic addition of the dimethoxycoumarin to 1,2,4-triazines was carried out in the presence of three-fold excess of methanesulfonic acid in DCM at room temperature and take place between positions 4 and 5 of coumarin and 1,2,4-triazine, respectively. The double oxidation step was achieved with 3.6 equivalent of DDQ. Selective oxidation of dihydrotriazine moiety, without affecting the tetrahydrobenzo fragment, was achieved using 1.2 equivalent of tetrachlorobenzoquinone (TCQ). The differences in the oxidation with TCQ and DDQ appear to be related to the higher oxidative potential of DDQ in contrast to TCQ. The advantages of the method are the elimination of the use of transition metals, the availability of starting materials, and the simplicity of the procedure. The proposed approach provides a two-step one-pot protocol for the synthesis of triazinyl benzocoumarins, precursors for the preparation of push-pull pyridinyl chromophore. Moiety ; Chemistry ; Nucleophile ; Triazine ; Methanesulfonic acid ; Nucleophilic substitution ; Combinatorial chemistry ; Medicinal chemistry ; Stereochemistry ; Organic chemistry ; Catalysis Synthesis and Characterization of Heterocyclic Compounds ; Synthesis and Biological Evaluation ; DNA and Nucleic Acid Chemistry
Authors: Mithlesh Yadav | Rekha Rao | Sunil Kumar | Archana Kapoor
Source: ChemistrySelect (article, 2023-12-01)
Field: Chemistry — Organic Chemistry

Exploration of N‐(6‐Indazolyl) benzenesulfonamide Derivatives as Potential Antioxidants and Antimicrobial Agents: Integrating Synthesis, In Silico Docking, and Bioactivity Profiling Abstract A new series of N‐(1‐(2‐chloropyrimidin‐4‐yl)‐1 H ‐indazol‐5‐yl) benzenesulfonamide derivatives ( 4 a – i ) and N‐(1‐(2‐chloropyrimidin‐4‐yl)‐6‐ethoxy‐1 H ‐indazol‐5‐yl) benzenesulfonamide derivatives ( 5 a – i ) was synthesized via reduction of 1‐(2‐halopyrimidin‐4‐yl)‐5‐nitro‐1 H ‐indazole (3) with SnCl 2 followed by reaction with various aryl sulphonyl chlorides in pyridine. The structures were confirmed using IR, 1 H‐NMR, 13 C‐NMR, and mass spectral methods. Compounds 4 a – i and 5 a – i were evaluated for antifungal and antibacterial activities against Gram‐negative and Gram‐positive bacteria. They also exhibited antioxidant potential in DPPH (IC 50 =0.094‐0.467 μmol/ml) and ABTS assays (IC 50 =0.101–0.496 μmol/ml). Remarkably, N‐(1‐(2‐chloropyrimidin‐4‐yl)‐1 H ‐indazol‐5‐yl)‐2‐nitrobenzenesulfonamide displayed the highest antibacterial activity, while N‐(1‐(2‐chloropyrimidin‐4‐yl)‐1 H ‐indazol‐5‐yl)‐4‐methoxybenzenesulfonamide showed excellent antifungal potential. Compound N‐(1‐(2‐chloropyrimidin‐4‐yl)‐1 H ‐indazol‐5‐yl)‐2‐nitrobenzenesulfonamide exhibited the most significant antioxidant activity. In this study, molecular dynamics simulations were utilized to rigorously examine the stability of ligand‐protein complexes, demonstrating a consistent and robust binding of the most potent compound within the target proteins′ binding sites. Computational assessments were further employed to predict the drug‐likeness and ADMET properties of the synthesized compounds. The results unequivocally confirmed the remarkable antioxidant and antimicrobial potential of all derivatives, a finding substantiated by comprehensive molecular docking analyses that revealed intricate interactions involving hydrogen bonds, electrostatic forces, and hydrophobic contacts. These findings collectively provide invaluable insights into the complex molecular structure and receptor target site dynamics, laying a strong foundation for the development of novel active antioxidant and antimicrobial agents with promising pharmaceutical implications. Chemistry ; ABTS ; Antimicrobial ; Carbon-13 NMR ; Aryl ; Stereochemistry ; Docking (animal) ; Combinatorial chemistry ; Proton NMR ; Indazole ; Antioxidant ; DPPH ; Medicinal chemistry ; Organic chemistry ; Alkyl Synthesis and biological activity ; Quinazolinone synthesis and applications ; Phenothiazines and Benzothiazines Synthesis and Activities
Authors: Nikola Sakač | Dubravka Madunić-Čačić | Dean Marković | Marija Jozanović
Source: Sensors (article, 2023-02-13)
Field: Chemistry — Organic Chemistry

Study of Cationic Surfactants Raw Materials for COVID-19 Disinfecting Formulations by Potentiometric Surfactant Sensor The behavior of a new 1,3-dioctadecyl-1<i>H</i>-imidazol-3-ium tetraphenylborate (DODI-TPB) surfactant sensor was studied in single and complex mixtures of technical grade QACs-benzalkonium chloride (BAC), <i>N,N</i>-didecyl-<i>N,N</i>-dimethylammonium chloride (DDAC), and <i>N,N</i>-dioctyl-<i>N,N</i>-dimethylammonium chloride (DOAC) usually used in COVID-19 disinfecting agents formulations. The results obtained with the new DODI-TPB sensor were in good agreement with data measured by a 1,3-dihexadecyl-1<i>H</i>-benzo[<i>d</i>]imidazol-3-ium-tetraphenylborate (DMI-TPB) surfactant sensor, as well as two-phase titration used as a reference method. The quantitative titrations of a two-component mixture of the cationic homologs (a) DDAC and DOAC; and (b) BAC and DOAC showed that the new DODI-TPB surfactant sensor can clearly distinguish two separate mixture components in a single potentiometric titration curve with two characteristic inflexion points. The consumption of SDS (used as a titrant) in the end-point 1 (EP 1) corresponded to the content of DDAC (or BAC), whereas the consumption in the end-point 2 (EP 2) corresponded to the total content of both cationic surfactants in the mixture. DOAC content in both mixtures can be calculated from the difference of the titrant used to achieve EP1 and EP2. The addition of nonionic surfactants resulted in the signal change decrease from 333.2 mV (1:0; no nonionic surfactant added) to 243.0 mV (1:10, <i>w</i>/<i>w</i>). The sensor was successfully tested in ten two-component COVID-19 disinfecting formulations. Potentiometric titration ; Titration ; Pulmonary surfactant ; Chemistry ; Cationic polymerization ; Benzalkonium chloride ; Tetraphenylborate ; Chloride ; Bromide ; Chromatography ; Sodium tetraphenylborate ; Nuclear chemistry ; Organic chemistry Antimicrobial agents and applications ; Analytical Chemistry and Sensors ; Environmental Chemistry and Analysis
Authors: Joëlle Obeid | Abdullah Shaito | Hiba El Hajj | Carine Deleuze‐Masquéfa | Pierre‐Antoine Bonnet | Marwan El‐Sabban | Jessica Saliba
Source: World Academy of Sciences Journal (article, 2023-06-30)
Field: Chemistry — Organic Chemistry

Biological applications of imiquimod analogues: An update (Review) The last decade witnessed intensive efforts in drug discovery and the emergence of thousands of molecules with potential for use as therapeutic targets. However, only a few hundred of these molecules reached the stage of clinical trials, with only a handful being translated from the bench to bedside. One such example is imiquimod, an immune response modifier belonging to the imidazoquinoline family. Imiquimod was first approved by the US Food and Drug Administration for the topical treatment of anal and genital warts and actinic keratosis, and later exhibited a potent antitumor activity. This promising activity inspired the development of several imidazoquinoxaline analogues and derivatives. The present review provides a comprehensive overview of the scientific literature on the chemical synthesis of imiquimod and several of its analogues, namely EAPB0203, EAPB0503 and EABP02303. The present review also discusses their preclinical properties and mechanisms of action in the context of cancer and parasitic infections, highlighting the worthiness of translating these activities into therapeutic drugs. Imiquimod ; Actinic keratosis ; Context (archaeology) ; Medicine ; Drug ; Food and drug administration ; Pharmacology ; Dermatology ; Biology ; Internal medicine Synthesis and Biological Evaluation ; Quinazolinone synthesis and applications ; CAR-T cell therapy research
Authors: Qamre Alam
Source: Bioinformation (article, 2023-06-30)
Field: Materials Science — Biomaterials

Molecular docking analysis of MCL-1 inhibitors for breast cancer management Myeloid leukemia 1 (MCL-1), a BCL-2 protein family member, acts as an anti-apoptotic protein by interacting with pro-apoptotic BCL-2 proteins. Its overexpression is frequently observed in numerous cancer types including breast cancer, and is closely linked to the initiation and progression of tumors as well as poor prognosis and resistance to therapeutic interventions. Here, a database of 3402 chemicals with established therapeutic activity against various diseases was chosen and systematically screened against the MCL-1 protein. Visual inspection and binding energy analysis revealed that the compounds OSU-03012, Raltitrexed, Ostarine (MK-2866), Dovitinib (TKI-258), and Varespladib (LY315920) had strong binding affinity for the MCL-1 protein. Notably, their binding affinity was higher than that of the control compounds. These compounds exhibited strong interactions with critical amino acid residues of the MCL-1 protein. Furthermore, these compounds shared several common amino acid residue interactions with the control compounds. These findings suggest that these compounds may be useful as MCL-1 inhibitors in the treatment of breast cancer. However, additional experimental validation is required to confirm these findings. Docking (animal) ; Amino acid ; Breast cancer ; Amino acid residue ; Cancer research ; Protein–protein interaction ; Cancer ; Chemistry ; Medicine ; Biochemistry ; Peptide sequence ; Gene ; Internal medicine Nanoparticle-Based Drug Delivery ; Cell death mechanisms and regulation ; Computational Drug Discovery Methods
Authors: Yu-min Shi | Jun Wang | Heng Yan
Source: Journal of Heterocyclic Chemistry (article, 2023-05-21)
Field: Chemistry — Organic Chemistry

The current scenario of furoxan hybrids with anticancer potential Abstract Cancer is one of the most common and deadliest diseases affecting millions of human beings globally. Treatment of cancer has achieved great advancements, and chemotherapy remains one of the most important means. However, the chemotherapy suffers from apparent limitations including drug resistance, systemic toxicity, adverse effects, and tumor recurrence, creating an urgent demand to develop novel anticancer chemotherapeutics. Furoxan derivatives could exert anticancer activity via releasing high concentrations of nitric oxide (NO), which could induce cellular apoptosis, arrest cell cycle, inhibit the migration and invasion of cells, and suppress angiogenesis. Hence, furoxan derivatives demonstrated potent in vitro and in vivo anticancer efficiency. In particular, furoxan hybrids, combination of other anticancer pharmacophores with furoxan moiety, demonstrated significant therapeutic effects on various cancers including drug‐resistant forms since these derivatives could act on multiple targets in cancer cells simultaneously. Accordingly, furoxan hybrids constitute an important source in the development of novel chemotherapeutic agents with anticancer activity. This review is to highlight the current scenario of furoxan hybrids with anticancer potential, covering articles published from 2012 to present. The structure–activity relationships and mechanisms of action are discussed to continuously open up a map for the remarkable exploration of more effective candidates. Furoxan ; Chemistry ; Pharmacophore ; Cancer cell ; In vivo ; Pharmacology ; Apoptosis ; Cancer ; In vitro ; Cancer research ; Nitric oxide ; Biology ; Medicine ; Biochemistry ; Biotechnology ; Internal medicine Synthesis and Biological Evaluation ; Bioactive Compounds and Antitumor Agents ; Synthesis and biological activity
Authors: Benjamin Nottelet | Sytze Buwalda | Cornelus F. van Nostrum | Xiaofei Zhao | Chao Deng | Zhiyuan Zhong | Ernest Cheah | Darren Svirskis | Chloe Trayford | Sabine van Rijt | Cécilia Ménard‐Moyon | Ravi Kumar | S. Kehr | Natan Roberto de Barros | Ali Khademhosseini | Han‐Jun Kim | Tina Vermonden
Source: Journal of Physics Materials (review, 2023-10-23)
Field: Materials Science — Biomaterials

Roadmap on multifunctional materials for drug delivery This Roadmap on drug delivery aims to cover some of the most recent advances in the field of materials for drug delivery systems (DDSs) and emphasizes the role that multifunctional materials play in advancing the performance of modern DDS<sub>s</sub> in the context of the most current challenges presented. The Roadmap is comprised of multiple sections, each of which introduces the status of the field, the current and future challenges faced, and a perspective of the required advances necessary for biomaterial science to tackle these challenges. It is our hope that this collective vision will contribute to the initiation of conversation and collaboration across all areas of multifunctional materials for DDSs. We stress that this article is not meant to be a fully comprehensive review but rather an up-to-date snapshot of different areas of research, with a minimal number of references that focus upon the very latest research developments. Drug delivery ; Drug ; Nanotechnology ; Computer science ; Medicine ; Materials science ; Pharmacology Nanoparticle-Based Drug Delivery ; Graphene and Nanomaterials Applications ; Hydrogels: synthesis, properties, applications