jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Xinpeng Sun | Wei Yu | Li‐Jing Min | Liang Han | Xuewen Hua | Jianjun Shi | Na-Bo Sun | Xing‐Hai Liu
Source: Molecules (article, 2023-04-11)
Field: Chemistry — Organic Chemistry

Synthesis, Structural Determination, and Antifungal Activity of Novel Fluorinated Quinoline Analogs A series of new fluorinated quinoline analogs were synthesized using Tebufloquin as the lead compound, 2-fluoroaniline, ethyl 2-methylacetoacetate, and substituted benzoic acid as raw materials. Their structures were confirmed by <sup>1</sup>H NMR, <sup>13</sup>C NMR, and HRMS. The compound 8-fluoro-2,3-dimethylquinolin-4-yl 4-(<i>tert</i>-butyl)benzoate (<b>2b</b>) was further determined by X-ray single-crystal diffraction. The antifungal activity was tested at 50 μg/mL, and the bioassay results showed that these quinoline derivatives had good antifungal activity. Among them, compounds <b>2b</b>, <b>2e</b>, <b>2f</b>, <b>2k</b>, and <b>2n</b> exhibited good activity (>80%) against <i>S. sclerotiorum</i>, and compound <b>2g</b> displayed good activity (80.8%) against <i>R. solani</i>. Quinoline ; Benzoic acid ; Antifungal ; Chemistry ; Bioassay ; Carbon-13 NMR ; Proton NMR ; Stereochemistry ; Ethyl benzoate ; Organic chemistry ; Biology ; Catalysis Synthesis and biological activity ; Synthesis and Biological Evaluation ; Fungal Plant Pathogen Control
Authors: Weicai Li | Lu Tan | Yijun Chen | Rui Liu | Zhongyu Qi | Shixuan Yuan | Zhanwen Huang | Siping Wei | Xi Du | Dong Yi
Source: Chinese Journal of Chemistry (article, 2023-09-25)
Field: Chemistry — Organic Chemistry

<scp>Metal‐Free</scp> Photocatalytic [4+2] Annulation of Acrylamides with <scp>2‐Benzyl</scp>‐2‐bromocarbonyls to Assemble Tetralin‐1‐carboxamides Comprehensive Summary Tetralin‐1‐carboxamides are frequently incorporated in myriad medicinally important molecules. However, their existing synthetic routes not only suffer from some drawbacks such as tedious procedures, harsh reaction conditions, narrow substrate scope, low yields, and environmental problems, but are also based upon the elaboration of uneasily available non‐linear tetralin derivatives. Herein, we describe a metal‐ and additive‐free visible light‐induced [4+2] annulation of two simple linear starting materials, namely acrylamides and 2‐benzyl‐2‐bromocarbonyls, through a cascade C(sp 3 )−Br/C(sp 2 )−H bond cleavage, double C−C bond formation, and aromatization sequence. The developed protocol provides a convenient, efficient, and green approach to a variety of tetralin‐1‐carboxamide derivatives with good functional group compatibility. Importantly, the resulting products could also undergo the LiCl‐mediated mono‐decarboxylative cyclization process to further furnish the architecturally novel bridged polycyclic imides with excellent cis ‐diastereoselectivities. Tetralin ; Chemistry ; Annulation ; Combinatorial chemistry ; Aromatization ; Bond cleavage ; Organic chemistry ; Stereochemistry ; Solvent ; Catalysis Catalytic C–H Functionalization Methods ; Radical Photochemical Reactions ; Sulfur-Based Synthesis Techniques
Authors: Bingwei Hu | Wenxin Yan | Peiyun Jiang | Ling Jiang | Yuan Xu | Jun Lin | Yinchun Jiao | Yi Jin
Source: Communications Chemistry (article, 2023-01-18)
Field: Chemistry — Organic Chemistry

Switchable synthesis of natural-product-like lawsones and indenopyrazoles through regioselective ring-expansion of indantrione Lawsones and indenopyrazoles are the prevalent structural motifs and building blocks in pharmaceuticals and bioactive molecules, but their synthesis has always remained challenging as no comprehensive protocol has been outlined to date. Herein, a metal-free, ring-expansion reaction of indantrione with diazomethanes, generated in situ from the N-tosylhydrazones, has been developed for the synthesis of lawsone and indenopyrazole derivatives in acetonitrile and alcohol solvents, respectively. It provides these valuable lawsone and pyrazole skeletons in good yields and high levels of diastereoselectivity from simple and readily available starting materials. DFT calculations were used to explore the mechanism in different solutions. The synthetic application example also showed the prospects of this method for the preparation of valuable compounds. Lawsone ; Regioselectivity ; Ring (chemistry) ; Combinatorial chemistry ; Chemistry ; Pyrazole ; Acetonitrile ; Natural product ; Organic chemistry ; Alcohol ; Computational chemistry ; Catalysis Cyclopropane Reaction Mechanisms ; Bioactive Compounds and Antitumor Agents ; Traditional and Medicinal Uses of Annonaceae
Authors: Eugenia Chukwu Cornelius | Michael H. Bartl | Louise Persson | Ruisheng Xiong | Daniela Cederfelt | Farshid Mashayekhy Rad | Thomas Norberg | Sarah Engel | Erik G. Marklund | Doreen Dobritzsch | Mikael Widersten
Source: Catalysis Science & Technology (article, 2023-01-01)
Field: Chemistry — Organic Chemistry

Engineered aldolases catalyzing stereoselective aldol reactions between aryl-substituted ketones and aldehydes An A129G/R134V/S166G triple mutant of fructose 6-phosphate aldolase (FSA) from Escherichia coli was further engineered with the goal to generate new enzyme variants capable of catalyzing aldol reactions between aryl substituted ketones and aldehydes. Aldol reaction ; Aldolase A ; Aryl ; Stereoselectivity ; Chemistry ; Escherichia coli ; Mutant ; Catalysis ; Fructose ; Enzyme ; Combinatorial chemistry ; Organic chemistry ; Stereochemistry ; Biochemistry Carbohydrate Chemistry and Synthesis ; Enzyme Catalysis and Immobilization ; Enzyme Structure and Function
Authors: Julie Lynch | James Sherwood | Con Robert McElroy | Jane Murray | Seishi Shimizu
Source: Analytical Methods (article, 2023-01-01)
Field: Chemistry — Spectroscopy

Dichloromethane replacement: towards greener chromatography <i>via</i> Kirkwood–Buff integrals Dichloromethane (DCM) is a useful and advantageous solvent used in pharmaceutical development due to its low cost, miscibility with other organic solvents, high volatility, and ability to solubilize drug molecules of variable polarities and functionalities. Despite this favourable behaviour, efforts to identify safer and more sustainable alternatives to hazardous, halogenated solvents is imperative to the expansion of green chemistry. In this work, bio-derived esters <i>tert</i>-butyl acetate, <i>sec</i>-butyl acetate, ethyl isobutyrate, and methyl pivalate are experimentally identified as safe and sustainable alternatives to directly replace DCM within thin-layer chromatography (TLC) in the analysis of small, common drug molecules. To elucidate the intermolecular interactions influencing retardation factors (<i>R</i><sub>f</sub>) a statistical thermodynamic framework, which quantifies the driving molecular interactions that yield empirical TLC measurements, is presented. Within this framework, we are able to deduce <i>R</i><sub>f</sub> dependence on polar eluent concentration, in the presence of a low-polar mediating solvent, between the stationary and mobile phases. The strength of competitive analyte-eluent (and analyte-solvent interactions) are quantified through Kirkwood-Buff integrals (KBIs); resulting KBI terms at the dilute eluent limit provide a theoretical foundation for the observed suitability of alternative green solvents for the replacement of dichloromethane in TLC. Dichloromethane ; Column chromatography ; Analyte ; Chemistry ; Solvent ; Chemical polarity ; Ethyl acetate ; Yield (engineering) ; Molecule ; Chromatography ; Organic chemistry ; Materials science Analytical Chemistry and Chromatography ; Crystallization and Solubility Studies ; Chemical and Physical Properties in Aqueous Solutions
Authors: Beatrice-Cristina Ivan | Ștefania‐Felicia Bărbuceanu | Camelia Mia Hotnog | Octavian Tudorel Olaru | Adriana Iuliana Anghel | Robert Ancuceanu | Mirela Mihăilă | Lorelei Irina Braşoveanu | Sergiu Shova | Constantin Drăghici | George Mihai Nițulescu | Florea Dumitraşcu
Source: International Journal of Molecular Sciences (article, 2023-07-19)
Field: Chemistry — Organic Chemistry

Synthesis, Characterization and Cytotoxic Evaluation of New Pyrrolo[1,2-b]pyridazines Obtained via Mesoionic Oxazolo-Pyridazinones New pyrrolo[1,2-<i>b</i>]pyridazines were synthesized by 3 + 2 cycloaddition reaction between mesoionic oxazolo-pyridazinones and methyl/ethyl propiolate. The mesoionic compounds were generated in situ by action of acetic anhydride on 3(2<i>H</i>)pyridazinone acids obtained from corresponding esters by alkaline hydrolysis followed by acidification. The structures of the compounds were confirmed by elemental analyses and IR, <sup>1</sup>H-NMR, <sup>13</sup>C-NMR, and X-ray diffraction data. The regioselectivity of cycloaddition was evidenced by NMR spectroscopy and confirmed by X-ray analysis. The compounds were evaluated for their cytotoxicity on plant cells (<i>Triticum aestivum</i> L.) and crustacean animal cells (<i>Artemia franciscana</i> Kellogg and <i>Daphnia magna</i> Straus). The results indicated that the tested compounds exhibited low toxicity on the plant cell (IC<sub>50</sub> values higher than 200 µM), while on Artemia nauplii no lethality was observed. Daphnia magna assay showed that pyrrolo[1,2-<i>b</i>]pyridazines <b>5a</b> and <b>5c</b> could exhibit toxic effects, whereas, for the other compounds, toxicity was low to moderate. Also, the cytotoxic effects of the compounds were tested on three human adenocarcinoma-derived adherent cell lines (colon LoVo, ovary SK-OV-3, breast MCF-7). The in vitro compound-mediated cytotoxicity assays, performed by the MTS technique, demonstrated dose- and time-dependent cytotoxic activity for several compounds, the highest anti-tumor activity being observed for <b>5a</b>, <b>2c,</b> and <b>5f</b>, especially against colon cancer cells. Mesoionic ; Chemistry ; Stereochemistry ; Combinatorial chemistry ; Organic chemistry Synthesis and Reactivity of Heterocycles ; Synthesis and Biological Evaluation ; Synthesis and biological activity
Authors: Meena Ghosh | Dieter Sorsche | Rezwana Binte Ahmed | Montaha Anjass
Source: ChemSusChem (article, 2023-08-24)
Field: Materials Science — Materials Chemistry

Stabilizing Decavanadate Cluster as Electrode Material in Sodium and Lithium‐ion Batteries Decavanadate ([V<sub>10</sub> O<sub>28</sub> ]<sup>6-</sup> , {V<sub>10</sub> }) clusters are a potential electrode material for lithium and post-lithium batteries; however, their low stability due to the solubility in liquid organic electrolytes has been challenging. These molecular clusters are also prone to transform into solid-state oxides at a moderate temperature needed in the typical electrode fabrication process. Hence, controlling the solubility and improving the thermal stability of compounds are essential to make them more viable options for use as battery electrodes. This study shows a crystal engineering approach to stabilize the cluster with organic guanidinium (Gdm<sup>+</sup> ) cation through the hydrogen-bonding interactions between the amino groups of the cation and the anion. The comparison of solubility and thermal stability of the Gdm{V<sub>10</sub> } with another cluster bearing tetrabutylammonium (Tba<sup>+</sup> ) cation reveals the better stability of cation-anion assembly in the former than the latter. As a result, the Gdm{V<sub>10</sub> } delivers better rate capability and cycling stability than Tba{V<sub>10</sub> } when tested as anode material in a half-cell configuration of a sodium-ion battery. Finally, the performance of the Gdm{V<sub>10</sub> } anode is also investigated in a lithium-ion battery full cell with LiFePO<sub>4</sub> cathode. Anode ; Lithium (medication) ; Electrolyte ; Solubility ; Inorganic chemistry ; Thermal stability ; Battery (electricity) ; Chemistry ; Electrochemistry ; Electrode ; Cathode ; Chemical engineering ; Materials science ; Physical chemistry ; Organic chemistry ; Thermodynamics Polyoxometalates: Synthesis and Applications ; Metal-Organic Frameworks: Synthesis and Applications ; Chemical Synthesis and Characterization
Authors: Kento Tsukiji | Takeru Hayakawa | Kazuya Kanemoto | Naohiko Yoshikai
Source: Asian Journal of Organic Chemistry (article, 2023-04-12)
Field: Chemistry — Organic Chemistry

Zinc‐Mediated Diastereoselective Annulation of Cyclopropanols with Alkylidenemalononitriles via Enolized Homoenolate Abstract A zinc‐mediated annulation reaction between cyclopropanols and alkylidenemalononitriles is reported. The reaction is promoted in the presence of Et 2 Zn and 1,4‐diazabicyclo[2.2.2]octane (DABCO) in DMSO at 80 °C, affording cyclopropane‐fused 6‐amino‐3,4‐dihydro‐2 H ‐pyran‐5‐carbonitrile derivatives in moderate to good yields with high diastereoselectivity. The reaction is proposed to involve an enolized homoenolate as the key reactive intermediate, which is generated through ring opening of zinc cyclopropoxide and enolization of the resulting zinc homoenolate. The enolate moiety of this reactive species undergoes Michael addition to the alkylidenemalononitrile, which is followed by ring closure of the resulting α‐functionalized homoenolate and intramolecular cyclization between the cyclopropoxide and one of the cyano groups. Chemistry ; Annulation ; Zinc ; Moiety ; Cyclopropane ; DABCO ; Octane ; Intramolecular force ; Pyran ; Medicinal chemistry ; Ring (chemistry) ; Stereochemistry ; Tautomer ; Organic chemistry ; Catalysis Cyclopropane Reaction Mechanisms ; Synthetic Organic Chemistry Methods ; Catalytic C–H Functionalization Methods
Authors: Tran Ni Kha | Nguyen Thanh | Van Man Tran | Khương Quoc Võ | Minh Tho Nguyen | Phạm Vũ Nhật
Source: ACS Omega (article, 2023-11-07)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Binding Mechanism and Surface-Enhanced Raman Scattering of the Antimicrobial Sulfathiazole on Gold Nanoparticles A combined study using the surface-enhanced Raman scattering (SERS) technique and quantum chemical calculations was carried out to elucidate the adsorption behavior of sulfathiazole, an antibiotic drug, on gold nanoparticles. The tetrahedral Au<sub>20</sub> cluster was used as a simple model to mimic a nanostructured gold surface. Computations using density functional theory with the PBE functional were performed in both the gas phase and aqueous medium using a continuum model. The drug is found to bind to the Au metals via the nitrogen of the thiazole ring. The interaction is also partially stabilized by the ring-surface π coupling rather than a sideway adsorption as previously proposed. In an aqueous solution, the drug molecule mainly exists as a deprotonated form, which gives rise to a much greater affinity toward Au nanoparticles as compared to the neutral forms. The drug adsorption further induces a significant alteration on the energy gap of the gold cluster Au<sub><i>n</i></sub>, which could result in an electrical noise. Notable SERS signals below 1600 cm<sup>-1</sup>, which result from a coupling of several vibrations including the ring breathing, C-C stretching, and N-H bending, could be employed for both qualitative and quantitative detection and assessment of sulfathiazole at trace concentrations. Adsorption ; Density functional theory ; Colloidal gold ; Raman scattering ; Aqueous solution ; Nanoparticle ; Chemistry ; Molecule ; Raman spectroscopy ; Materials science ; Computational chemistry ; Physical chemistry ; Nanotechnology ; Organic chemistry Gold and Silver Nanoparticles Synthesis and Applications ; Nanocluster Synthesis and Applications ; Quantum Dots Synthesis And Properties
Authors: Jun‐Chao Liu | Hang Peng | Xiao-Gang Chen | Hui‐Peng Lv | Xian‐Jiang Song | Ren‐Gen Xiong | Wei‐Qiang Liao
Source: JACS Au (article, 2023-03-20)
Field: Materials Science — Electronic, Optical and Magnetic Materials

Fluorination Enables Dual Ferroelectricity in Both Solid- and Liquid-Crystal Phases Ferroelectric materials are a special type of polar substances, including solids or liquid crystals. However, obtaining a material to be ferroelectric in both its solid crystal (SC) and liquid crystal (LC) phases is a great challenge. Moreover, although cholesteric LCs inherently possess the advantage of high fluidity, their ferroelectricity remains unknown. Here, through the reasonable H/F substitution on the fourth position of the phenyl group of the parent nonferroelectric dihydrocholesteryl benzoate, we designed ferroelectric dihydrocholesteryl 4-fluorobenzoate (4-F-BDC), which shows ferroelectricity in both SC and cholesteric LC phases. The fluorination induces a lower symmetric polar <i>P</i>1 space group and a new solid-to-solid phase transition in 4-F-BDC. Beneficial from fluorination, the SC and cholesteric LC phases of 4-F-BDC show clear ferroelectricity, as confirmed by well-shaped polarization-voltage hysteresis loops. The dual ferroelectricity in both SC and cholesteric LC phases of a single material was rarely found. This work offers a viable case for the exploration of the interplay between ferroelectric SC and LC phases and provides an efficient approach for designing ferroelectrics with dual ferroelectricity and cholesteric ferroelectric liquid crystals. Ferroelectricity ; Liquid crystal ; Materials science ; Polar ; Crystallography ; Polarization (electrochemistry) ; Antiferroelectricity ; Chemistry ; Dielectric ; Optoelectronics ; Physics ; Physical chemistry Liquid Crystal Research Advancements ; Solid-state spectroscopy and crystallography ; Photorefractive and Nonlinear Optics
Authors: Jiaqi Guo | Weiyi Tan | Hongjian He | Bing Xu
Source: Angewandte Chemie International Edition (article, 2023-07-20)
Field: Materials Science — Biomaterials

Autohydrolysis of Diglycine‐Activated Succinic Esters Boosts Cellular Uptake Rapid cellular uptake of synthetic molecules remains a challenge, and the motif frequently employed to generate prodrugs, succinic ester, unfortunately lowers the efficacy of the desired drugs due to their slow ester hydrolysis and low cell entry. Here we show that succinic ester-containing diglycine drastically boosts the cellular uptake of supramolecular assemblies or prodrugs. Specifically, autohydrolysis of the diglycine-activated succinic esters turns the nanofibers of the conjugates of succinic ester and self-assembling motif into nanoparticles for fast cellular uptake. The autohydrolysis of diglycine-activated succinic esters and drug conjugates also restores the efficacy of the drugs. 2D nuclear magnetic resonance (NMR) suggests that a "U-turn" of diglycine favors intramolecular hydrolysis of diglycine-activated succinic esters to promote autohydrolysis. As an example of rapid autohydrolysis of diglycine-activated succinic esters for instant cellular uptake, this work illustrates a nonenzymatic bond cleavage approach to develop effective therapeutics for intracellular targeting. Chemistry ; Succinic anhydride ; Succinic acid ; Prodrug ; Hydrolysis ; Combinatorial chemistry ; Biochemistry ; Organic chemistry Supramolecular Self-Assembly in Materials ; Chemical Synthesis and Analysis ; RNA Interference and Gene Delivery
Authors: Yitao Sun | Chun Zhang | Lixin Gao | Min‐Min Liu | Yuting Yang | Andong Shao | Yubo Zhou | Yun‐Long Zhu | Jia Li | Wenlong Wang
Source: ChemPhysChem (article, 2023-06-24)
Field: Chemistry — Organic Chemistry

Design, Synthesis and Evaluation of Fluorescent Properties of Benzothiazole Derivatives Fluorescence imaging is conducive to establish a bridge between molecular biology and clinical medicine, and provides new tools for disease process research, early diagnosis, and efficacy evaluation, because of the advantages of rapid imaging and nondestructive detection. Herein, a series of fluorescent molecules with thiadiazole, or thiazole, or benzothiazole cores were designed and synthesized to develop more excellent fluorescent molecules in bio-imaging. According to theoretical and experimental methods, we found that benzothiazole derivative 14 B with conjugate expansion by (4-aminophenyl) ethynyl group was the most excellent fluorescent molecule among all the investigated compounds and exhibited low cytotoxicity and strong blue and green fluorescence by confocal cell imaging. Benzothiazole ; Fluorescence ; Thiazole ; Molecule ; Conjugate ; Combinatorial chemistry ; Chemistry ; Derivative (finance) ; Fluorescence-lifetime imaging microscopy ; Confocal ; Nanotechnology ; Materials science ; Organic chemistry Click Chemistry and Applications ; Synthesis and biological activity ; Nanoplatforms for cancer theranostics
Authors: Ashok H Akabari | Jasmina Surati | Sagar Patel | Bhumin Pathak | Arun Patel | C. K. N. Patel | Sagarkumar K Patel
Source: Separation Science Plus (article, 2023-06-17)
Field: Chemistry — Analytical Chemistry

Development and validation of high‐performance thin layer chromatographic method for simultaneous quantitation of novel combination perindopril erbumine and moxonidine hydrochloride Abstract The primary purpose of the present study was to develop and validate a high‐performance thin‐layer chromatography method for quantitatively determining an anti‐hypertensive agent, perindopril erbumine, and moxonidine hydrochloride in bulk and synthetic mixture. The densitometric procedure was performed on aluminum thin‐layer chromatography plates pre‐coated with silica gel 60F254, employing a combination of dichloromethane: toluene: methanol: ammonia (7:1:2:0.1 v/v/v/v) as the mobile phase. The thin‐layer chromatography scanner was operated in absorbance mode at a wavelength of 223 nm to evaluate densitograms. The linearity of the method was established in the range of 1000–5000 ng/band for perindopril erbumine and 40–200 ng/band for moxonidine hydrochloride; the correlation coefficient (r 2 ) was 0.9993 and 0.9983, respectively. The values of a limit of detection (186.06 and 3.51 ng/band, respectively, for perindopril erbumine and moxonidine hydrochloride) and limit of quantification (620.23 and 11.73 ng/band, respectively, for perindopril erbumine and moxonidine hydrochloride) have demonstrated the sensitivity of the developed method. The reported process was precise in both intra‐day and inter‐day analysis; the percentage relative standard deviation of peak area was less than 2% and has an accuracy within 100 ± 2%. The developed method has the potential to quantify perindopril erbumine and moxonidine hydrochloride from its synthetic mixture without any interference from other components or in quality control laboratories. Chromatography ; Perindopril ; Detection limit ; High performance thin layer chromatography ; Moxonidine ; Chemistry ; Absorbance ; Thin-layer chromatography ; Chemometrics ; Correlation coefficient ; Analytical Chemistry (journal) ; Mathematics Analytical Methods in Pharmaceuticals ; Blood Pressure and Hypertension Studies ; Pesticide Residue Analysis and Safety
Authors: Kanako Nozawa‐Kumada | So Onuma | Kanako Ono | Tomohiro Kumagai | Yuki Iwakawa | Katsuhiko Sato | Masanori Shigeno | Yoshinori Kondo
Source: Chemistry - A European Journal (article, 2023-01-04)
Field: Chemistry — Organic Chemistry

Transition‐Metal‐Free Intermolecular Hydrocarbonation of Styrenes Mediated by NaH/1,10‐Phenanthroline A transition-metal-free intermolecular coupling reaction of halocompounds with styrenes in the presence of NaH and 1,10-phenanthroline was developed. This reaction afforded hydrocarbonated products with complete anti-Markovnikov selectivity. The method allows the use of a wide range of halocompounds, including aryl and alkyl halides, and good functional group tolerance. Detailed mechanistic studies indicated that an anilide anion generated in situ by the NaH-mediated reduction of 1,10-phenanthroline works as an electron donor and a hydrogen source. Phenanthroline ; Chemistry ; Intermolecular force ; Aryl ; Alkyl ; Markovnikov's rule ; Halide ; Selectivity ; Functional group ; Medicinal chemistry ; Polymer chemistry ; Combinatorial chemistry ; Catalysis ; Organic chemistry ; Molecule ; Regioselectivity Catalytic C–H Functionalization Methods ; Catalytic Cross-Coupling Reactions ; Cyclopropane Reaction Mechanisms