jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Yu. V. Karpenko | О. І. Панасенко
Source: Current issues in pharmacy and medicine science and practice (article, 2021-06-01)
Field: Chemistry — Organic Chemistry

Search for antibacterial activity in a number of new S-derivatives (1,2,4-triazole-3(2H)-yl)methyl)thiopyrimidines The relevance of the study of 1,2,4-triazole derivatives with pyrimidine fragment is due to the synthesis of potential broad-spectrum antibacterial drugs, low molecular weight inducers of interferon, and antitumor agents, search for molecular descriptors of their structure, important for establishing patterns “structure – biological activity”. The aim of the work is a computer search for the antibacterial action of new hybrids of 1,2,4-triazole-3(2H)-thiol with a pyrimidine fragment in relation to 5 test cultures, to establish the dependence of “structure – action”. Materials and methods. For an in-depth study of the antibacterial activity of derivatives of 1,2,4-triazole-3(2H)-thiol hybrids with a pyrimidine fragment, 4 test cultures of museum strains of gram-positive, gram-negative bacteria and one species of fungi were selected. In silico studies were performed using regression and classification QSAR models. Results. Derivatives of 1,2,4-triazole-3(2H)-thiol hybrids with a pyrimidine moiety showed high antibacterial activity against gram-negative microorganisms (E. coli, P. aeruginosa). The obtained experimental results allowed to establish not only the role of the main structural features of the compounds in the manifestation of antimicrobial properties, but also to evaluate the effectiveness of the created classification and regression QSAR models. Based on the presented parameters for individual predictive QSAR models, it is possible to conclude about the effectiveness, stability and feasibility of using these models to search for new S-derivatives (1,2,4-triazole-3(2H)-yl)methyl)thiopyrimidines as promising antimicrobial agents. Conclusions. It was found that the studied derivatives of hybrids of 1,2,4-triazole-3(2H)-thiol with a pyrimidine fragment showed high antibacterial activity against gram-negative microorganisms. The developed QSAR classification models based on the percentage of correctly predicted compounds (70 %) are the most effective in comparison with regression (50 %) for the search for new antimicrobial agents in a number of derivatives of hybrids 1,2,4 triazole-3(2H)-thiol with pyrimidine fragment. Quantitative structure–activity relationship ; Pyrimidine ; Antimicrobial ; In silico ; Chemistry ; Antibacterial activity ; Stereochemistry ; Moiety ; Combinatorial chemistry ; 1,2,4-Triazole ; Molecular descriptor ; Computational chemistry ; Organic chemistry ; Biochemistry ; Biology ; Bacteria Synthesis and biological activity ; Synthesis and Characterization of Heterocyclic Compounds ; Phenothiazines and Benzothiazines Synthesis and Activities
Authors: Sukumar Bepary | Bishyajit Kumar Biswas | Prosenjit Ghosh | Md. Aminul Haque | Quang De Tran
Source: Journal of Molecular Docking (article, 2021-12-30)
Field: Chemistry — Organic Chemistry

N-acetylation of 2-aminobenzothiazoles with Acetic Acid for Evaluation of Antifungal Activity and In Silico Analysis Acetamides (S30A1 and S30) were synthesized from benzo[d]thiazol-2-amine and 6-nitrobenzo[d]thiazol-2-amine by direct use of acetic acid instead of acetylating agents. The usual acetylating agents, acetic anhydride and acetyl chloride are very unstable especially because of their high sensitivity to environmental moisture. Thus, acetylation by direct use of acetic acid was searched as an alternative approach for synthesizing acetanilides. In this study, acetamides were synthesized with a yield of 88% and 82% respectively. The synthesized compounds were then screened for antifungal activity. At a concentration of 300 µg/disc, S30A1 showed 18 mm, 28 mm, 20 mm, and 16 mm zone of inhibitions against Penicillium notatum, Candida albicans, Aspergillus flavus, and Aspergillus niger, respectively. The standard miconazole was used at 50 µg/disc concentration. An in silico analysis was done for the possible binding modes in the C. albicans N-myristoyltransferase enzyme. Acetic anhydride ; Acetylation ; Acetic acid ; Aspergillus flavus ; Chemistry ; Candida albicans ; Aspergillus niger ; Miconazole ; Amine gas treating ; Organic chemistry ; Biochemistry ; Antifungal ; Food science ; Microbiology ; Biology Synthesis and biological activity ; Antifungal resistance and susceptibility ; Click Chemistry and Applications
Authors: Zahra Sadeghian | Mohammad Bayat | Fatemeh Safari
Source: Research Square (preprint, 2021-12-28)
Field: Chemistry — Organic Chemistry

Sequential Four-Component Synthesis And Antitumor Activity Screening of Spiro[chromene-indolo[2,1-b]quinazoline] And Spiro[indolo[2,1-b]Quinazoline-pyrano[3,2-c]chromene] Quinazoline ; Component (thermodynamics) ; Chemistry ; Stereochemistry ; Combinatorial chemistry ; Physics Multicomponent Synthesis of Heterocycles ; Quinazolinone synthesis and applications ; Synthesis and biological activity
Authors: Ismiyarto Ismiyarto | Niken Windi Saputri | Liswinda Zafirah Rahmatia | Purbowatiningrum Ria Sarjono | Ngadiwiyana Ngadiwiyana | Nor Basid Adiwibawa Prasetya | Damar Nurwahyu Bima
Source: Jurnal Kimia VALENSI (article, 2021-06-04)
Field: Materials Science — Biomaterials

Synthesis of Mn(II) Complexes-Carboxymethyl Chitosan Schiff Base Salicylaldehyde and Antibacterial Activity The development of compounds with a better antibacterial activity is highly needed. One way to achieve this is by modifying the structure of the compound using chitosan as a starting material, because of its abundant natural source in Indonesia, its biodegradable properties, and its structure where free amines are present. This study aims to obtain Mn(II) -Carboxymethyl Chitosan Schiff Base-Salicylaldehyde complex to increase its antibacterial activity against Staphylococcus aureus (Gram positive) and Escherichia coli (Gram negative). Schiff Base carboxymethyl chitosan-salicylaldehyde was synthesized from carboxymethyl chitosan with salicylaldehyde. Next, the Schiff Base Carboxymethyl Chitosan-Salicylaldehyde was complexed with MnCl2.4H2O and then characterized by FTIR, UV-Vis Spectrophotometer, and AAS and tested for antibacterial activity with the disc diffusion method against Staphylococcus aureus and Escherichia coli. The product of Carboxymethyl Chitosan Schiff Base-salicylaldehyde is a brownish yellow solid with a yield of 64% (w/w) and has antibacterial activity against Staphylococcus aureus (clear zone diameter 11 mm) and Escherichia coli (clear zone diameter 13 mm). The product of Mn(II) Complexes-Carboxymethyl Chitosan Schiff Base-salicylaldehyde is a black solid with a yield of 59% (w/w) and has antibacterial activity against Staphylococcus aureus (clear zone diameter 13 mm) and Escherichia coli (clear zone diameter 17 mm). Salicylaldehyde ; Chitosan ; Schiff base ; Antibacterial activity ; Nuclear chemistry ; Chemistry ; Escherichia coli ; Staphylococcus aureus ; Polymer chemistry ; Organic chemistry ; Biochemistry ; Bacteria ; Biology Nanocomposite Films for Food Packaging ; Medicinal Plant Research ; Nanoparticles: synthesis and applications
Authors: Jacklyn N. Hall | Praveen Bollini
Source:  (preprint, 2021-05-06)
Field: Chemistry — Inorganic Chemistry

Role of Metal Identity and Speciation in the Low-Temperature Oxidation of Methane over Tri-Metal Oxo Clusters Clarity as to the role of metal identity and oxidation state in effecting redox and acid-catalyzed turnovers is oftentimes precluded by a high degree of heterogeneity in site speciation, a limitation that can be overcome through the use of well-defined poly-metal clusters hosted by metal organic framework materials- accomplished in the present case using MIL-100(M) for the low temperature oxidation of methane with N2O. Transient kinetic data point to a) methoxy species mediating methane conversion, b) partial and deep oxidation occurring over metal sites distinct in oxidation state, c) chromium clusters amplifying the propensity toward C-C bond formation, and d) the relative velocity of propagation of water and methanol concentration fronts playing a determinative role in maximizing C2 oxygenate selectivity. The study captures the utility of using classes of materials inherently endowed with a high level of definition and uniformity in advancing the elucidation of structure-catalytic property relationships. Methane ; Metal ; Catalysis ; Chemistry ; Oxidation state ; Chromium ; Methanol ; Genetic algorithm ; Redox ; Anaerobic oxidation of methane ; Inorganic chemistry ; Partial oxidation ; Oxygenate ; Organic chemistry Metal-Organic Frameworks: Synthesis and Applications ; Catalytic Processes in Materials Science ; Catalysis and Oxidation Reactions
Authors: İncilay Süslü | Sevilay Erdoğan Kablan | Cihat Şafak | Rahime Şimşek
Source: Journal of Research in Pharmacy (article, 2021-01-05)
Field: Chemistry — Electrochemistry

Electrochemical detection of antioxidant activities of 4-indolyl-5-oxo-6,6 (or 7,7)- dimethyl-1,4,5,6,7,8-hexahydroquinoline derivatives Antioxidants used in different medical and industrial fields in order to prevent and delay oxidative stress. They play a crucial role in the protecting biological systems against many diseases. 1,4-dihydropyridines are known as calcium channel modulators. Electrochemical techniques are simple, cheap and fast detection techniques and require small amounts of sample, so they offer advantages over commonly used analytical methods. Voltammetric methods have been applied to investigated the antioxidant activity of compounds in different fields. The proposed work is aimed at examining the electrochemical behavior of the 1,4-dihydropyridines by differential pulse voltammetry and hence the assessment of its antioxidant activity from the cathodic reduction peak of oxygen values. The peak current due to oxygen reduction was found to be proportional to the 1,4-dihydropyridines concentration of 0.1 -0.5 mg/mL. The coefficient of antioxidant activity of 1,4-dihydropyridine derivatives were calculated and compared each other. Nifedipine used as a reference drug that is known as the calcium channel modulator and it is used to compare the antioxidant activities of 1,4-dihydropyridine-derived compounds. Electrochemistry ; Antioxidant ; Chemistry ; Pharmacology ; Combinatorial chemistry ; Business ; Organic chemistry ; Medicine ; Physical chemistry ; Electrode Electrochemical Analysis and Applications ; Multicomponent Synthesis of Heterocycles ; Free Radicals and Antioxidants
Authors: Hyunseung Kim | Jonggeol Na | Won Bo Lee
Source: arXiv (Cornell University) (preprint, 2021-02-27)
Field: Materials Science — Materials Chemistry

Generative chemical transformer: attention makes neural machine learn molecular geometric structures via text Chemical formula is an artificial language that expresses molecules as text. Neural machines that have learned chemical language can be used as a tool for inverse molecular design. Here, we propose a neural machine that creates molecules that meet some desired conditions based on a deep understanding of chemical language (generative chemical Transformer, GCT). Attention-mechanism in GCT allows a deeper understanding of molecular structures, beyond the limitations of chemical language itself that cause semantic discontinuity, by paying attention to characters sparsely. We investigate the significance of language models to inverse molecular design problems by quantitatively evaluating the quality of generated molecules. GCT generates highly realistic chemical strings that satisfy both a chemical rule and grammars of a language. Molecules parsed from generated strings simultaneously satisfy the multiple target properties and are various for a single condition set. GCT generates de novo molecules, and this is done in a short time that human experts cannot. These advances will contribute to improving the quality of human life by accelerating the process of desired material discovery. Computer science ; Generative grammar ; Transformer ; Artificial intelligence ; Rule-based machine translation ; Parsing ; Natural language processing ; Set (abstract data type) ; Programming language ; Engineering Machine Learning in Materials Science ; Computational Drug Discovery Methods ; Protein Structure and Dynamics
Authors: Hongzhi Hu | Wenbo Yang | Zihui Liang | Zezhu Zhou | Qingcheng Song | Weijian Liu | Xiangtian Deng | Jian Zhu | Xin Xing | Binglong Zhong | Baichuan Wang | Shangyu Wang | Zengwu Shao | Yingze Zhang
Source: Research Square (preprint, 2021-04-08)
Field: Chemistry — Organic Chemistry

Amplification of Oxidative Stress With Lycorine and Gold-Based Nanocomposites for Synergistic Cascade Cancer Therapy Lycorine ; Oxidative stress ; Cascade ; Cancer therapy ; Cancer ; Chemistry ; Cancer research ; Nanotechnology ; Materials science ; Medicine ; Internal medicine ; Biochemistry ; Organic chemistry ; Chromatography ; Alkaloid Chemical synthesis and alkaloids ; Alkaloids: synthesis and pharmacology ; Cholinesterase and Neurodegenerative Diseases
Authors: Elham Badali | Mahshid Hosseini | Narges Mahmoodi | Sajad Hassanzadeh | Vajihe Taghdiri Nooshabadi | Arash Goodarzi | Maryam Jalessi | Zohreh Arabpour | Mehdi Khanmohammadi
Source: Research Square (preprint, 2021-10-06)
Field: Materials Science — Biomaterials

Production of Cell Enclosing Silk Derivative Microsphere in Uniform Size Distribution Through Coaxial Microfluidic Device and Horseradish Crosslinking Reaction Abstract Background Silk fibroin (SF) as a natural polymer holds great potential in biomedical research because of its biocompatibility, easy processing, high toughness, and strength. However, slow gelation time has narrowed its applications, specifically in cell-laden microparticles that are versatile structures for tissue engineering due to their unique features. In addition, most crosslinking methods used to decrease gelation time did not occur in a mid-condition. Methods This study aimed to use modified SF with phenol conjugation to accelerate crosslinking mediated via horseradish peroxidase (HRP)/ hydrogen peroxide (H 2 O 2 ) in a co-flow high-throughput microfluidic device for the ultimate goal of cell-laden silk fibroin-phenol (SF-Ph) microparticles formation. The physical and biochemical properties of fabricated cell-laden SF-Ph were evaluated to reveal its potential for tissue engineering. Results The monodisperse microparticles in shape and size were formed in various diameters changing from 300 to 80 µm by altering oil phase velocity from SF-Ph substrate. More than 90% cell viability and three times cells upregulation of mitochondrial activity of enclosed-cells in microparticles with 150 ± 32 µm diameters revealed that these structures were suitable subcultures produced through a mild process based on morphological and MTT assays. It was noticed that cells approximately cover the microparticles until the 15th day. Conclusion Spherical micro-tissue formation in microparticles, resulting from cell growth promoted by cell-cell and cell-matrix interactions, adds significant weight to this method's applications. Fibroin ; Biocompatibility ; Horseradish peroxidase ; Microfluidics ; Tissue engineering ; Chemistry ; Dispersity ; SILK ; Chemical engineering ; Materials science ; Viability assay ; Polymer ; Nanotechnology ; Polymer chemistry ; Biomedical engineering ; Cell ; Composite material ; Organic chemistry ; Biochemistry Silk-based biomaterials and applications ; Periodontal Regeneration and Treatments ; Bone Tissue Engineering Materials
Authors: Nazariy T. Pokhodylo | V. S. Matiychuk
Source: Biopolymers and Cell (article, 2021-08-31)
Field: Chemistry — Organic Chemistry

Evaluation of the antiproliferative activity of selected 1,2,3-triazole-4-carboxylic acids — key fragments and precursors of antitumor 1,2,3-triazole-4-carboxamides Aim. To evaluate in vitro antiproliferative effect of selected 1,2,3-triazole-4-carboxylic acids, which are the key fragments and precursors of antitumor 1,2,3-triazole-4-carboxamides. Methods. Organic synthesis, in vitro cytotoxicity assay, MTT assay, spectrophotometry, statistical analysis. Results. The selected 1,2,3-triazole carboxylic acids and their esters synthesized according to a convenient synthetic procedure were tested for their anticancer activity in NCI60 cell lines within 9 cancer types at the 60 human tumour cell lines panel. These preliminary results allowed identifying the most active compounds and finding the structure-activity relations. The most promising 1,2,3-triazole-4-carboxylic fragments were selected for the design of 1,2,3-triazole-4-carboxamides for screening anticancer activity. Conclusions. The obtained results of antitumour activity of the studied derivatives are interesting for the discovery of selective and active anticancer agents among 1,2,3-triazole-4-carboxamides in terms of a fragment-based drug discovery (FBDD) concept, that proves the necessity of further studies. Chemistry ; 1,2,4-Triazole ; 1,2,3-Triazole ; Triazole ; Carboxylic acid ; Combinatorial chemistry ; Stereochemistry ; Organic chemistry Synthesis and Characterization of Heterocyclic Compounds ; Click Chemistry and Applications ; Synthesis and biological activity
Authors: Wenqing Shui | Ronghui Lou | Weizhen Liu | Rongjie Li | Shanshan Li | Xuming He
Source: Research Square (preprint, 2021-04-22)
Field: Chemistry — Spectroscopy

DeepPhospho: Accelerate DIA phosphoproteome profiling by Deep Learning Profiling (computer programming) ; Computer science ; Computational biology ; Deep learning ; Data science ; Artificial intelligence ; Biology Advanced Proteomics Techniques and Applications ; Machine Learning in Bioinformatics ; Metabolomics and Mass Spectrometry Studies
Authors: Clémence Blanc | Ian Edwin Cock
Source: Pharmacognosy Communications (article, 2021-01-27)
Field: Chemistry — Organic Chemistry

An Examination of the Antioxidant Capacity, Antibacterial Activity and Toxicity of Commercial Kale and Spirulina Powders Introduction: The development of antibiotic resistant bacteria has resulted in treatment failure for the current antibiotic regimen against many bacteria. A corresponding decrease in the development of new antibiotic therapies has highlighted the urgent need for the discovery of new antibiotics. An examination of ‘superfoods’ is an attractive option due to the high antioxidant capacities and beneficial secondary compounds reported in many ‘superfoods’. This study was undertaken to test kale and spirulina extracts for the ability to inhibit the growth of a panel of bacterial pathogens of human importance. Methods: Commercially sourced kale and spirulina powders were extracted and tested for antimicrobial activity using modified disc diffusion and liquid dilution MIC methods. Toxicity was evaluated using an Artemia franciscana nauplii bioassay. Results: The methanolic and aqueous extracts of kale and spirulina displayed noteworthy growth inhibitory activity against P. mirabilis. The aqueous spirulina extract was a particularly good inhibitor of P. mirabilis, with MIC values as low as 220μg/mL. In contrast, all extracts were ineffective or of low inhibitory activity against all other bacteria tested. All extracts were non-toxic in the Artemia nauplii bioassay, confirming their suitability as natural antibacterial therapies. Conclusion: These studies indicate that aqueous kale and spirulina extracts are promising inhibitors of P. mirabilis growth and may be useful in the prevention and treatment of rheumatoid arthritis, as well as other diseases caused by that bacterium. Spirulina (dietary supplement) ; Antioxidant capacity ; Antioxidant ; Toxicity ; Chemistry ; Antibacterial activity ; Food science ; Traditional medicine ; Toxicology ; Biology ; Medicine ; Biochemistry ; Organic chemistry ; Bacteria Edible Oils Quality and Analysis ; Phytochemicals and Antioxidant Activities
Authors: Xiaoxiang Chen | Jiatong Li | Yu‐Hui Fang | Xueqing Wang | Guangchao Liu | Yunfei Wang | Xinyu Deng | Xiaodan Gu | Shang‐Da Jiang | Ting Lei
Source: Research Square (preprint, 2021-08-13)
Field: Materials Science — Polymers and Plastics

High-mobility semiconducting polymers with different spin ground states Spin (aerodynamics) ; Polymer ; Condensed matter physics ; Ground transportation ; Materials science ; Political science ; Physics ; Engineering ; Nuclear magnetic resonance ; Transport engineering Conducting polymers and applications ; Organic Electronics and Photovoltaics ; Advanced Sensor and Energy Harvesting Materials
Authors: Nia N. P | M S Siti | P Muchlisyam
Source: Asian Journal of Pharmaceutical Research and Development (article, 2021-06-15)
Field: Chemistry — Analytical Chemistry

Simultaneous Determination of Amlodipine and Valsartan in Tablet By UV Spectrophotometry With Successive Ratio Method Objectives: This study aims to develop a spectrophotometric method by successive ratio method in simultaneous determination of AML and VLS on tablet preparations without separation.&#x0D; Methods: This study aims to develop a spectrophotometric method by successive ratio method in simultaneous determination of AML and VLS on tablet preparations without separation and then tested for validity based validation parameters, namely linearity, accuracy, precision, LOD and LOQ and intraday and interday. Then, this method was applied to determine the levels of AML and VLS on dosage tablet.&#x0D; Result: Manipulating the ratio spectra of the binary mixture allowed their determination at 358,4 nm and 247,4 nm and in the concentration ranges of (4-12 µg/mL) and (6-18 µg/mL) for amlodipine and valsartan, respectively&#x0D; Conclusion: The successive ratio method can be used to determine the levels of a mixture of amlodipine and valsartan drugs.&#x0D; Valsartan ; Amlodipine ; Chromatography ; Dosage form ; Spectrophotometry ; Accuracy and precision ; Materials science ; Chemistry ; Analytical Chemistry (journal) ; Mathematics ; Medicine ; Statistics ; Internal medicine Analytical Methods in Pharmaceuticals
Authors: Jungkweon Choi | Siin Kim | Mina Ahn | Jungmin Kim | Dae Won Cho | Kyung‐Ryang Wee | Hyotcherl Ihee
Source: Research Square (preprint, 2021-10-28)
Field: Chemistry — Spectroscopy

Singlet Fission Dynamics Modulated by Molecular Configuration in Covalently Linked Pyrene Dimers, Anti- and Syn-1,2-di(Pyrenyl)Benzene Pyrene ; Fission ; Chemistry ; Covalent bond ; Benzene ; Singlet state ; Photochemistry ; Physics ; Organic chemistry ; Nuclear physics ; Excited state Molecular Spectroscopy and Structure ; Chemical Reaction Mechanisms ; Advanced NMR Techniques and Applications