jablonkagroup/rise_ai_scientists huggingface dataset:
Authors: Man Pang Tang | Yulin Deng | Yixiang Shi | Samuel Kin‐Man Lai | Xin‐Yu Pang | Chunyu Liu | Wei Jiang | Lihui Zhu | Ho Yu Au‐Yeung
Source: ChemRxiv (preprint, 2023-10-04)
Field: Chemistry — Organic Chemistry

Water and Air Stable Copper(I) Complexes of Tetracationic Catenane Ligands for Oxidative C–C Cross-Coupling Aqueous soluble and stable Cu(I) molecular catalysts featuring a catenane ligand composed of two mechanically interlocked, cationic macrocycles are reported. The mechanical bond in the catenane ligand not only fine-tunes the coordination sphere and kinetically stabilizes the Cu(I) against air oxidation and disproportionation, but also prevents the dissociation of the otherwise electrostatically repulsive cationic macrocycles which are essential for the good water solubility and sustained reactivity of the catalyst. These catenane Cu(I) complexes are active catalysts for the oxidative C–C coupling of indoles and tetrahydroisoquinolines in water with a good substrate scope. The successful use of the catenane ligands in exploiting Cu(I) for oxidative catalysis under aqueous conditions using H2O2 as a green oxidant thus highlights the many unexplored potential of mechanical bonding as a molecular design element in developing new transition metal catalysts. Catenane ; Chemistry ; Cationic polymerization ; Catalysis ; Ligand (biochemistry) ; Dissociation (chemistry) ; Aqueous solution ; Disproportionation ; Metal ; Polymer chemistry ; Combinatorial chemistry ; Organic chemistry ; Molecule Catalytic C–H Functionalization Methods ; Catalytic Cross-Coupling Reactions ; Synthesis and Catalytic Reactions
Authors: Aliakbar Mohammadlou | Ankush Chakraborty | Mitchell Maday | Xiaopeng Yin | Zheng Li | Hadi Gholami | Kumar Dilip Ashtekar | Richard J. Staples | William D. Wulff | Babak Borhan
Source: ChemRxiv (preprint, 2023-02-23)
Field: Chemistry — Inorganic Chemistry

Structure Guided Design of VANOL-imidodiphosphorimidate Catalysts for the Catalytic Enantioselective Bromo Spiroketalization Reaction This report presents a structure-guided approach for the optimization of VANOL-derived imidodiphosphorimidates as catalysts for the halonium-ion-induced spiroketalization reaction. Fine tuning of the catalyst active site, alongside enhanced acidity, were required to achieve high catalytic activity for the spiroketalization reaction. A wide range of substrates were well tolerated yielding halogenated spiroketals in high yields, diastereoselectivities, and enantioselectivities. Catalysis ; Enantioselective synthesis ; Combinatorial chemistry ; Reaction conditions ; Chemistry ; Range (aeronautics) ; Organic chemistry ; Materials science ; Composite material Vanadium and Halogenation Chemistry ; Chemical Synthesis and Reactions ; Synthesis of Indole Derivatives
Authors: Antonio Angelastro | Alexey Barkhanskiy | William R. F. Goundry | Perdita E. Barran | Sabine L. Flitsch
Source: ChemRxiv (preprint, 2023-01-31)
Field: Chemistry — Organic Chemistry

Horner-Wadsworth-Emmons Olefination of Proteins and Glycoproteins Chemo-selective and site-specific modifications of proteins are fundamental to the advancement of biological and pharmaceutical sciences, from understanding the basis of cellular biology to development of biotherapeutics. Recent successes in bioconjugation chemistry have inspired the search for more biocompatible chemical reactions, which has prompted us to investigate Horner-Wadsworth-Emmons (HWE) olefinations, iconic reactions used widely in organic synthesis that would give rise to new selective protein olefinations. Our choice of HWE olefinations was inspired by the growing number of methods for the generation of aldehydes as transient reactive groups in proteins and the potential for mild and simple reaction conditions. Here we show that HWE on aldehydes produced by both chemical and enzymatic methods is fully compatible with physiological conditions and highly selective in small and large proteins, including therapeutic antibodies. By exploiting the wide range of easily accessible HWE reagents provided by organic chemistry, we show that the reaction kinetics can be fine-tuned over orders of magnitude by judicious use of substituents. The electrophilic nature of the HWE products can be tuned to allow for subsequent nucleophilic additions, including thiol- and phospha-Michael additions, enabling two-step dual labelling strategies. Our results demonstrate that HWE olefination of aldehydes in proteins provide efficient and selective bioconjugation chemistries that are orthogonal to existing methods. Bioconjugation ; Chemistry ; Electrophile ; Reagent ; Chemical biology ; Nucleophile ; Combinatorial chemistry ; Organic chemistry ; Biochemistry Click Chemistry and Applications ; Chemical Synthesis and Analysis ; Biochemical and Structural Characterization
Authors: Jaafar Sataar Shia | Marwan S. Ibrahim | Asmaa Safwan Al-darraji
Source: South Asian Research Journal of Pharmaceutical Sciences (article, 2023-12-06)
Field: Chemistry — Organic Chemistry

Various of Chemical and Pharmacological Applications of 1,3,4-Thiadiazole and It’s Derivative 1,3,4-Thiadiazole is a heterocyclic compound that has been widely studied for its diverse pharmacological activities. The compound is synthesized using different methods, including cyclization of linear organic derivative. The compound has been shown to exhibit various bioactivity, including its property as anticancer toward human cancers, antibacterial, diuretic, antitubercular, antifungal, and leishmanicidal agents, additionally, 1,3,4-thiadiazole derivatives have been shown to influence the central nervous system, displaying anti-inflammatory, anticonvulsant, analgesic, anxiolytic and antidepressant effects. 1,3,4-thiadiazole and its derivatives have been a subject of extensive research in the field of medicinal chemistry. These compounds exhibit a wide range of pharmacological activities, making them valuable candidates for drug development. The structural versatility of 1,3,4-thiadiazole derivatives allows for the fine-tuning of their pharmacological effects. The 1,3,4-thiadiazole moiety in a molecule enhances its bioactivity. Medicinal chemists have explored the SAR (Structure-Activity Relationship) of these derivatives to understand how different substitutions and modifications impact their pharmacological profiles. Synthesis and pharmacological activities of 1,3,4-thiadiazole and also its derivatives represent a vibrant area of research with promising implications for the progress of new therapeutic agents across various medical domains. Antifungal ; Moiety ; Chemistry ; Combinatorial chemistry ; Pharmacology ; Biological activity ; Lead compound ; Stereochemistry ; In vitro ; Medicine ; Biochemistry Synthesis and biological activity ; Synthesis and Characterization of Heterocyclic Compounds
Authors: Myung‐Han Yoon | Ji Hwan Kim | Roman Halaksa | Il‐Young Jo | Hyungju Ahn | Peter A. Gilhooly‐Finn | Inho Lee | Sungjun Park | Christian B. Nielsen
Source: Research Square (preprint, 2023-05-11)
Field: Materials Science — Polymers and Plastics

Peculiar Transient Behaviors of Organic Electrochemical Transistors Governed by Ion Injection Directionality Abstract Despite the growing interest in dynamic behaviors at the frequency domain, there exist very few studies on molecular orientation-dependent transient responses of organic mixed ionic–electronic conductors. In this research, we investigated the effect of ion injection directionality on transient electrochemical transistor behaviors by developing a model mixed conductor system. Two polymers with similar electrical, ionic, and electrochemical characteristics but distinct molecular orientations were successfully synthesized by varying the co-monomer unit (2,2’-bithiophene or phenylene) in conjunction with a novel 1,4-dithienylphenylene-based monomer. The comprehensive electrochemical analysis suggests that the molecular orientation affects the length of the ion-drift pathway, which is directly correlated with ion mobility, resulting in peculiar OECT transient responses. These results provide the general insight into molecular orientation-dependent ion movement characteristics as well as high-performance device design principles with fine-tuned transient responses. Directionality ; Transient (computer programming) ; Transistor ; Ion ; Electrochemistry ; Materials science ; Optoelectronics ; Electrode ; Chemistry ; Electrical engineering ; Computer science ; Engineering ; Voltage Conducting polymers and applications ; Organic Electronics and Photovoltaics ; Advanced Memory and Neural Computing
Authors: Yi Ren | Zhaoxin Liu
Source: Synlett (article, 2023-11-20)
Field: Chemistry — Inorganic Chemistry

Design of Indole-Functionalized Phosphepines towards New Organic Chromophores Abstract Organic chromophores emerged as diverse functional materials in the areas of organic catalysis, toxic materials sensing, bio-imaging, and organic electronic devices. With rich chemical and electronic structures, main-group elements have been extensively implanted in organic chromophores to fine-tune the chemical/electronic structures and optoelectronic properties. In this Synpact article, we present a concise overview of the development of phosphorus (P)-containing organic chromophores, further highlighting our recent contributions in the field. A new aspect of combining the P element with the indole moiety was pursued to construct a new series of seven-membered P-organic chromophores; namely, indole-functionalized phosphepines. The new combination endowed the system with rich chemical and electronic structures, for which intriguing photophysical properties were consequently revealed. The combination provided an efficient synthetic protocol to access new P-heterocycles and also offered a new strategy to design functional organic chromophores. Chromophore ; Moiety ; Chemistry ; Indole test ; Organic synthesis ; Combinatorial chemistry ; Nanotechnology ; Organic chemistry ; Catalysis ; Materials science Synthesis and characterization of novel inorganic/organometallic compounds ; Organophosphorus compounds synthesis ; Organoselenium and organotellurium chemistry
Authors: Tatiana Yu. Kopnova | Linara R. Yakupova | Natalya G. Belogurova | Еlena V. Kudryashova
Source: Preprints.org (preprint, 2023-11-06)
Field: Materials Science — Biomaterials

Human Serum Albumin Grafted by Monomeric and Polymeric &lt;em&gt;β&lt;/em&gt;-Cyclodextrin as Drug Delivery System for Levofloxacin with Improved Pharmacological Properties Human serum albumin (HSA) is multifunctional protein, known to be a natural carrier for a number of endogenous and exogenous compounds, including drugs. Formulating anticancer drugs with HSA is a clinically validated approach to improve the pharmacological properties and provide targeted delivery (passive and active) of cytotoxic payload to the tumor (such as in Abraxane). A number of receptors facilitating HSA uptake from systemic circulation have been characterized. What is interesting, such uptake may differ depending on the nature and quantity of ligands bound to HSA. Based on this, one might like to modify the HSA in a way that its distribution is more favorable for certain therapeutic purposes, thus ensuring more efficient delivery of the therapeutic cargo to disease site. E.g. Levofloxacin (LV), broad spectrum antibiotic drug, could benefit from extended systemic exposure, and stronger interaction with plasma proteins could be useful for this purpose. We have engrafted monomeric or polymeric CDs on the surface of HSA molecules to strengthen the LV adsorption (CD-LV dissociation constant is three orders of magnitude lower than that for HSA-LF). We have found that (HSA-HPolS)conj+LV exhibited the highest activity against E. coli, whereas (HSA-HPCD)conj+LV was the most effective against B. subtilis; and both HSA conjugates were more potent than LV alone or LV with HSA. Further fine-tuning of HSA could yield an improvement in biodistribution, and thus a more favorable risk/benefit ratio. Human serum albumin ; Chemistry ; Biodistribution ; Drug delivery ; Pharmacology ; Drug ; Distribution (mathematics) ; Monomer ; Biochemistry ; Medicine ; In vitro Nanoparticle-Based Drug Delivery ; Protein Interaction Studies and Fluorescence Analysis ; Hemoglobin structure and function
Authors: Ahmed M. El‐Zohry | Ravi Kumar Venkatraman | Amal Hassan Tolba | Radek Cibulka
Source: ChemRxiv (preprint, 2023-12-19)
Field: Chemistry — Physical and Theoretical Chemistry

Ultrafast Excited State Dynamics for FeCl3 as an Efficient Photo-Oxidant In this study, we investigate the excited state dynamics of FeCl3 in various solvents using ultrafast transient absorption technique to unravel the effective performance of FeCl3 as a photocatalyst in oxidizing various aromatic substrates under visible and sunlight irradiation. We demonstrate that the key step leading to the formation of [Cl•Fe(II)Ln]* species is the charge transfer from the chloride ligand to the metal Fe atom. These species can engage in geminate and non-geminate pathways; however, the latter fashion is the critical step in determining the electron transfer from the substrate to the catalyst. Such primary oxidation step of the substrate can occur at the fastest of 110 ps time scale. Remarkably, utilizing methanol as an alternative solvent to acetonitrile resulted in the absence of transient signals as MeOH molecules, after replacing the inner sphere molecules surrounding FeCl3, exhibit a higher efficiency in quenching the [Cl•Fe(II)Ln]* species compared to MeCN. Our ultrafast studies pave the way for controlling these reaction rates for earth abundant materials through fine tuning of ligands and organic substrates. Photochemistry ; Ultrafast laser spectroscopy ; Acetonitrile ; Quenching (fluorescence) ; Excited state ; Substrate (aquarium) ; Oxidizing agent ; Electron transfer ; Chemistry ; Methanol ; Catalysis ; Solvent ; Chloride ; Photocatalysis ; Metal ; Molecule ; Ultrashort pulse ; Chemical physics ; Fluorescence ; Spectroscopy ; Organic chemistry Photochemistry and Electron Transfer Studies ; Oxidative Organic Chemistry Reactions ; Radical Photochemical Reactions
Authors: Liman Hou | Yushuang Zhang | Yipeng Zhang | Shang‐Da Jiang | Mingfeng Wang
Source: ChemRxiv (preprint, 2023-05-29)
Field: Chemistry — Spectroscopy

Tunable quantum coherence of organic luminescent radical qubits centered in star-like block copolymers and self-assembling nanostructures Electronic or nuclear spins such as inorganic ‘nitrogen-vacancy’ centers in diamond and other defects in silicon represent a promising type of quantum bits (qubits) for applications in quantum information processing, data storage as well as quantum sensing. However, it remains challenging to achieve scalable and spatially defined organization of a large number of spins as qubits. Therefore, development of new materials and technologies to regulate spin-spin distance and interaction plays an important role in preservation of quantum coherence and realization of coherent exchange of information between spin qubits. Herein, we report that spatially defined organization of organic radicals as electronic spins can be realized via a strategy of block copolymer self-assembly. We demonstrate quantum coherence and spin-lattice relaxation of organic luminescent radical spins can be facilely tuned using a library of well-defined star-like block copolymers containing a common core of tris[4-(p-benzyl)-2,6-dichlorophenyl]methyl radical in the center, from which diblock polyesters are grafted via controllable ring-opening polymerization. The fine tuning of the incompatibility and the volume ratio of the two blocks of polyesters leads to not only a series of self-assembling patterns (i.e., spheres, cylinders, lamellae, and gyroids) with phase-separation of the spins in the nanometer scale, but also tunable spin-lattice relaxation dynamics and spin coherence lifetimes that strongly depend on the lengths and rigidities of the polymeric matrices surrounding the organic radicals as molecular spins. Such strategy of block copolymer self-assembly may offer a generally applicable approach to integrating and organizing molecular spins as promising qubits into scalable architectures and functional devices towards cutting-edge applications in quantum information processing, quantum computation and spintronics. Spins ; Qubit ; Materials science ; Chemical physics ; Copolymer ; Coherence (philosophical gambling strategy) ; Nitrogen-vacancy center ; Quantum ; Nanotechnology ; Physics ; Condensed matter physics ; Quantum mechanics ; Polymer Advanced NMR Techniques and Applications ; Synthesis and Properties of Aromatic Compounds ; Electron Spin Resonance Studies
Authors: Joseph Watson | Ruth Pollard | Marc K. Etherington | Jonathan P. Knowles
Source: ChemRxiv (preprint, 2023-07-02)
Field: Chemistry — Organic Chemistry

A modular approach to tuning the charge transfer properties of photoluminescent quinine analogues. We have shown that Pd-catalysed cascade processes provide molecular access to rigid quinoline-containing tetracylic amines. This enables fine-tuning of the through-space charge transfer (TSCT) state formation by variation of both N-aryl distance and quinoline substitution. It was observed that decreasing the N-aryl distance enhanced the formation of the TSCT species giving control over emission colour and photoluminescence quantum yield. Methoxylation of the quinoline unit decreases the propensity of TSCT formation. This systematic study provides great insight for TSCT formation with impact on further understanding dimeric, excimeric and exciplex species. Quinoline ; Photoluminescence ; Modular design ; Aryl ; Chemistry ; Photochemistry ; Charge (physics) ; Excimer ; Cascade ; Chemical physics ; Materials science ; Fluorescence ; Organic chemistry ; Optoelectronics ; Physics ; Computer science ; Optics Synthesis and Biological Evaluation ; Click Chemistry and Applications ; Chemistry and Chemical Engineering
Authors: Sedigheh Ehsanimehr | Peyman Najafi Moghadam | Wim Dehaen | Vahid Shafiei‐Irannejad
Source: Research Square (preprint, 2023-05-10)
Field: Materials Science — Biomaterials

Multi-Stimuli-Responsive Biocompatible Magnetic Nanocarrier as Drug delivery System to MC7 Breast Cancer Cells <title>Abstract</title> Efforts are ongoing to develop effective controlled-release therapeutic systems through innovative functional targeted drug delivery systems (TDDS). Functional polymeric nanocarriers are crucial in delivering therapeutic drugs efficiently into tumors. This study designed a redox/pH-responsive functional drug delivery platform with ligands for targeting MC7 breast cancer cells using a core-shell biocompatible magnetic nanocarrier. The process involved synthesizing oleic acid-coated Fe3O4@SiO2 nanoparticles, modifying pluronic F127 (PF 127) with maleic anhydride and aminating it to form PF127-NH2, linking L-cysteine to PF127-NH2, and condensing carboxymethyl-β-cyclodextrin (CM-β-CD) to PF127-NH2/L-cysteine, which was targeted by folic acid (FA). The resulting PF127-NH2/L-cysteine-CM-β-CD-FA formed LCMNPs-SS in the presence of oleic acid-coated Fe3O4@SiO2. Doxorubicin (DOX) was used as a model drug and loaded into the LCMNPs-SS nanocarrier. The LCMNPs-SS nanocarrier exhibited excellent properties for controlled release, with release rate and level controllable by adding an external magnet and adjusting the DTT concentration. Additionally, the LCMNPs-SS nanocarrier could disassemble under the effects of oxidant or pH, allowing for fine-tuning of drug release in response to temperature and pH or multiple stimuli. Nanocarriers ; Drug delivery ; Chemistry ; Drug ; Poloxamer ; Oleic acid ; Targeted drug delivery ; Doxorubicin ; Drug carrier ; Pharmacology ; Materials science ; Nanotechnology ; Biophysics ; Combinatorial chemistry ; Copolymer ; Biochemistry ; Medicine ; Organic chemistry ; Polymer ; Chemotherapy Nanoparticle-Based Drug Delivery ; Graphene and Nanomaterials Applications ; Nanoplatforms for cancer theranostics
Authors: Jibin Alex Abraham | Hidetoshi Tsuruda | Shigeki Mori | Masatoshi Ishida | Hiroyuki Furuta
Source: Journal of Inorganic Biochemistry (article, 2023-11-22)
Field: Materials Science — Materials Chemistry

Synthesis and photothermal conversion properties of sandwich N-fused porphyrin rhodium-μ-dichloride dimer complexes: π-extended analog of pentamethylcyclopentadienyl dirhodium(III)-μ-dichloride dimer Chemistry ; Rhodium ; Porphyrin ; Dimer ; Photothermal therapy ; Cyclopentadienyl complex ; Photochemistry ; Chromophore ; Derivative (finance) ; Ligand (biochemistry) ; Catalysis ; Organic chemistry ; Nanotechnology Porphyrin and Phthalocyanine Chemistry ; Nanoplatforms for cancer theranostics ; Luminescence and Fluorescent Materials
Authors: Jcm Ho | Ankit K. Yadav | Andrzej Gładysiak | Andrew P. Carpenter | Anjali Verma | Matthew A. Cranswick | Adrian Henle | M. A. Subramanian | Joe E. Baio | Kyriakos C. Stylianou
Source: ChemRxiv (preprint, 2023-12-04)
Field: Chemistry — Inorganic Chemistry

Tuning Enantioselective Drug Adsorption in Isoreticular Homochiral Metal-Peptide Frameworks through Proximity Pore Interactions Pharmaceutical research places great importance on the stereochemistry and enantioseparation of racemic drugs due to the potential variations in pharmacological and toxicological properties displayed by different enantiomers as they interact with the body’s metabolic pathway. Metal-organic frameworks (MOFs) are porous adsorbents that can be designed to possess homochirality within their structures, enabling tunable porosity and enantioselective adsorption. In our study, we present the synthesis of five novel and homochiral Co-L-GG(R) MOFs (where L-GG = glycyl-L(S)-glutamic acid and R = bipyridyl (bipy) pillar ligands). These isoreticular MOFs were synthesized using the ligand extension strategy. This approach allowed us to systematically control the pore sizes of the MOFs, enabling fine-tuning of the enantioselective adsorption of racemic drugs, primarily DL-Penicillamine (Pen). Our findings reveal that the pore size greatly influences enantioselective adsorption, where too large or too small pores hinder the proximity-driven dispersive interactions between the drug and the pore surface, resulting in poor enantioselective adsorption of Pen. We achieved an enantiomeric excess (ee) of 60.1% (L over D), increasing to a maximum 76.1% ee using Co-L-GGvinylbipy by tuning proximity interactions in saturated pores. These results were accomplished by controlling the drug saturation within the MOF pores, promoting favorable interactions. Enantioselective synthesis ; Adsorption ; Enantiomer ; Chemistry ; Metal-organic framework ; Ligand (biochemistry) ; Homochirality ; Porosity ; Combinatorial chemistry ; Stereochemistry ; Chemical engineering ; Organic chemistry ; Catalysis ; Receptor Metal-Organic Frameworks: Synthesis and Applications ; Chemical Synthesis and Analysis ; Dendrimers and Hyperbranched Polymers
Authors: Tianyu Li
Source: ChemRxiv (preprint, 2023-02-20)
Field: Materials Science — Materials Chemistry

Particle Size and Pore Size Selection on Ordered Mesoporous Silica Controlling both particle size and pore size is critical when using mesoporous silica for fundamental studies. Pore size can be adjusted by modifying the reaction conditions during synthesis, but achieving a narrow particle size selection can be challenging. However, by allowing mesoporous silica to sediment in water, we can take advantage of the fact that particles of different sizes settle at different speeds in liquid. This approach enables us to obtain mesoporous silica particles with the exact pore size but different particle sizes or particles with varying pore sizes but the same particle size. This fine-tuning of particle size and pore size ensures precise control of the properties of mesoporous silica and is essential for many applications in various fields. Particle size ; Mesoporous silica ; Mesoporous material ; Materials science ; Particle (ecology) ; Nanotechnology ; Chemical engineering ; Mesoporous organosilica ; Chemistry ; Geology ; Organic chemistry ; Engineering Mesoporous Materials and Catalysis ; Zeolite Catalysis and Synthesis ; Catalytic Processes in Materials Science