bluuebunny/crossref_metadata_2025_split huggingface dataset:
Design, Synthesis, Biological Evaluation and in Silico Studies of Curcumin Pyrrole Conjugates
Authors: Gogoi Nishi Gandha , Rahman Aziza , Dutta Pankaj , Saikia Jiban , Baruah Anupaul , Handique Jyotirekha G. 
Published: March 2024

AbstractCurcumin conjugated heterocyclic compounds are potent candidates with drug likeness against various bacterial pathogens. A set of curcumin‐based pyrrole conjugates (CPs) were synthesized and characterized by FT‐IR, 1H and 13C NMR and HR‐MS techniques. The results of free radical scavenging activity of the synthesized CPs, evaluated by FRAP and CUPRAC assays, showed the potency of these compounds as effective antioxidants. CP3 exhibits the highest antioxidant activity amongst the CPs. The bactericidal efficacy of CPs was screened against ESKAP bacterial pathogens, and CPs were found to possess better antibacterial property than curcumin, specifically against staphylococcus aureus bacteria. In addition, serum albumin (BSA and HSA) binding interaction of these CPs were determined by UV‐visible and fluorescence spectrophotometric techniques. In‐silico molecular docking study was performed to determine the binding patterns of molecular targets against Staphylococcus aureus tyrosyl tRNA synthetase, and serum albumin proteins. The structure‐activity relationship showed that the presence of multiple phenolic hydroxyl groups, and electron withdrawing groups on the structure of CP molecule, enhances its antioxidant and antibacterial activity, respectively.
Ephedra intermedia Schrenk & C. A. Mey Methanol Extract: Nanoencapsulation by Mini‐Emulsion Polymerization and its Release Trend under Simulated Conditions of the Human Body
Authors: Mahdavi Behnam , Ebrahimi Sanaz , Farzi Gholam Ali , Maleki Behrooz , Mohammadhosseini Majid 
Published: March 2024

AbstractIn this research, the extract of Ephedra intermedia Schrenk & C.A.Mey. was encapsulated using the mini‐emulsion polymerization method based on methyl methacrylate polymers with a nanometer size. The encapsulated extract was characterized using different analytical techniques. Furthermore, the loading efficiency and release of the plant extract were examined. FT‐IR spectroscopy confirmed the formation of an expectational product. The TEM and SEM imaging showed a spherical morphology for the prepared encapsulated extract. The average size of poly‐methyl‐methacrylate nanoparticles containing Ephedra extract was found to be approximately 47 nm. The extract loading efficiency and encapsulation efficiency test demonstrated a dose‐depending behavior on E. intermedia extract for both analyses, which is highly advantageous for traversing biological barriers. The release assay shows a controlled release for the extract at phosphate buffer solution (PBS). A 38 % release was calculated after 36 hours. The results obtained from the present study reveal that encapsulating the plant extract is a suitable alternative to control and increase their medicinal properties.
New Analogues of Amides and Quinolinones Produced by Streptomyces sp. YIM S01983
Authors: Li Xia , Zhu Dou‐Ying , Liu Xi‐Ru , Liu Hong‐Jian , Tang Shu‐Kun , Cai Le , Zhao Li‐Xing 
Published: March 2024

AbstractStreptomide (1), a new amide analogue, streptomynone (2), a new quinolinone, and ten known compounds including three aliphatic acids (3‐5), two amides (6‐7), four cyclic dipeptides (8‐11), and an adenosine (12) were isolated from the fermentation broth of Streptomyces sp. YIM S01983 isolated from a sediment sample collected in Bendong Village, Huadong Town, Chuxiong, China. Their structures were determined by analysis of the 1D/2D‐NMR and HR‐ESI‐MS spectra. Compound 12 presented weak antimicrobial activities against Candida albicans and Aligenes faecalis (MIC=64 μg/mL). Compounds 7 and 12 showed weak cytotoxic activity against MHCC97H.
Synthesis of Pharmaceutically Relevant Arylamines Enabled by a Nitroreductase from Bacillus tequilensis
Authors: Russo Sara , Luján Alejandro Prats , Fraaije Marco W. , Poelarends Gerrit J. 
Published: March 2024

AbstractArylamines are essential building blocks for the manufacture of valuable pharmaceuticals, pigments and dyes. However, their current industrial production involves the use of chemocatalytic procedures with a significant environmental impact. As a result, flavin‐dependent nitroreductases (NRs) have received increasing attention as sustainable catalysts for more ecofriendly synthesis of arylamines. In this study, we assessed a novel NR from Bacillus tequilensis, named BtNR, for the synthesis of pharmaceutically relevant arylamines, including valuable synthons used in the manufacture of blockbuster drugs such as vismodegib, sonidegib, linezolid and sildenafil. After optimizing the enzymatic reaction conditions, high conversion of nitroaromatics to arylamines (up to 97 %) and good product yields (up to 56 %) were achieved. Our results indicate that BtNR has a broad substrate scope, including bulky nitro benzenes, nitro pyrazoles and nitro pyridines. Hence, BtNR is an interesting biocatalyst for the synthesis of pharmaceutically relevant amine‐functionalized aromatics, providing an attractive alternative to traditional chemical synthesis methodologies.
Design of New Bis(1,2,3‐triazol‐1‐yl)methane‐Based Nitrogen Ligands: Synthesis and Coordination Chemistry
Authors: Martínez de Sarasa Buchaca Marc , de la Cruz‐Martínez Felipe , Naranjo Jesús , Rodríguez Ana M. , de la Torre María C. , Castro‐Osma José A. , Sierra Miguel A. , Lara‐Sánchez Agustín 
Published: March 2024

AbstractThe reaction between bis(1,2,3‐triazol‐1‐yl)methane derivatives and nBuLi and various aldehydes, yielded novel neutral ligand precursors incorporating alcohol functional groups. The resulting compounds exhibited distinct characteristics depending on the steric hindrance of the aldehyde employed. In instances where aromatic aldehydes were utilized, functionalization occurred at the methine group bridging both triazole rings. Conversely, the use of pivalic aldehyde prompted functionalization at the C5 position of the triazole ring. These compounds were subsequently employed as ligand precursors in the synthesis of organometallic aluminum and zinc complexes, yielding dinuclear complexes with high efficiency. The structural elucidation of all compounds was accomplished through spectroscopic methods and validated by X‐ray crystallography. Preliminary catalytic investigations into the coupling reaction of cyclohexene oxide and CO2 revealed that aluminum and zinc complexes catalyzed the selective formation of polyether and polycarbonate materials, respectively.
Unravelling the Role of Free Radicals in Photocatalysis
Authors: Chen Yao , Xu Shuyang , Fang Wen Chun , Zhang Hanyun , Zhang Ting , Lv Fujian , Yue Yinghong , Bian Zhenfeng 
Published: March 2024

AbstractFree radicals are increasingly recognized as active intermediate reactive species that can participate in various redox processes, significantly influencing the mechanistic pathways of reactions. Numerous researchers have investigated the generation of one or more distinct photogenerated radicals, proposing various hypotheses to explain the reaction mechanisms. Notably, recent research has demonstrated the emergence of photogenerated radicals in innovative processes, including organic chemical reactions and the photocatalytic dissolution of precious metals. To harness the potential of these free radicals more effectively, it is imperative to consolidate and analyze the processes and action modes of these photogenerated radicals. This conceptual paper delves into the latest advancements in understanding the mechanics of photogenerated radicals.
Cycloaddition Reactions of Epoxides and CO2 Catalyzed by Bifunctional Rare‐Earth Metal Complexes Bearing Amino‐Bridged Tris(phenolato) Ligands
Authors: Chen Yongjie , Wang Yanwei , Nong Jun , Yuan Dan , Yao Yingming 
Published: March 2024

Comprehensive SummaryEight zwitterionic rare earth metal complexes stabilized by amino‐bridged tris(phenolato) ligands bearing quaternary ammonium side‐arms were synthesized and characterized. These complexes were used as single‐component catalysts for the cycloaddition of CO2 and epoxides, and their catalytic activities are obviously higher than those of their binary analogues. Further studies revealed that the halide anions (Cl–, Br–, I–) and the metal complexes influenced the catalytic activity, and the lanthanum complex bearing iodide anion showed the highest catalytic activity for this addition reaction. A variety of mono‐substituted epoxides were converted to cyclic carbonates in good to excellent yields (55%—99%) with high selectivity (> 99%) at 30 °C and 1 bar CO2, whereas internal epoxides required higher both reaction temperatures (60—120 °C) and catalyst loading (2 mol%) for high yields. The catalyst was recyclable for four times without noticeable loss of catalytic activity. Based on the results of kinetic studies and in situ IR reactions, a plausible reaction mechanism was proposed.
Metal‐Free Electrochemical Trifluoromethylation of Imidazole‐Fused Heterocycles with Trifluoromethyl Thianthrenium Triflate
Authors: Ge Chang , Qiao Lipeng , Zhang Yuyang , Sun Kai , An Jiangzhen , Peng Mei , Chen Xiaolan , Qu Lingbo , Yu Bing 
Published: March 2024

Comprehensive SummaryA novel and eco‐friendly electrochemical activation of trifluoromethyl thianthrenium triflate (TT–CF3+OTf−) for trifluoromethylation of imidazole‐fused heteroaromatic compounds was established. This method involves the direct electrolysis of TT–CF3+OTf− without the requirement of external oxidants or catalysts, aligning with the principles of green chemistry. A wide range of imidazole‐fused heteroaromatic compounds including imidazo[1,2‐a]pyridines and benzo[d]imidazo[2,1‐b]thiazoles have been successfully trifluoromethylated using this technique, exhibiting excellent compatibility with various functional groups and a broad substrate scope. Moreover, the method's applicability for one‐pot sequential reactions enables the reduction of waste and resource consumption by eliminating the need for intermediate purification steps.
Iodinated 4,4’‐Bipyridines with Antiproliferative Activity Against Melanoma Cell Lines
Authors: Peluso Paola , Mamane Victor , Spissu Ylenia , Casu Giuseppina , Dessì Alessandro , Dallocchio Roberto , Sechi Barbara , Palmieri Giuseppe , Rozzo Carla 
Published: March 2024

AbstractIn the last decade, biological processes involving halogen bond (HaB) as a leading interaction attracted great interest. However, although bound iodine atoms are considered powerful HaB donors, few iodinated new drugs were reported so far. Recently, iodinated 4,4’‐bipyridines showed interesting properties as HaB donors in solution and in the solid state. In this paper, a study on the inhibition activity of seven halogenated 4,4’‐bipyridines against malignant melanoma (MM) cell proliferation is described. Explorative dose/response proliferation assays were first performed with three 4,4’‐bipyridines by using four MM cell lines and the normal BJ fibroblast cell line as control. Among them, the A375 MM cell line was the most sensitive, as determined by MTT assays, which was selected to evaluate the antiproliferative activity of all 4,4’‐bipyridines. Significantly, the presence of an electrophilic iodine impacted the biological activity of the corresponding compounds. The 3,3’,5,5’‐tetrachloro‐2‐iodo‐4,4’‐bipyridine showed significant antiproliferation activity against the A375 cell line, and lower toxicity on BJ fibroblasts. Through in silico studies, the stereoelectronic features of possible sites determining the bioactivity were explored. These results pave the way for the utilization of iodinated 4,4’‐bipyridines as templates to design new promising HaB‐enabled inhibitors of MM cell proliferation.
Radiation‐induced effects on TGF‐β and PDGF receptor signaling in cancer‐associated fibroblasts
Authors: Yang Nannan , Hellevik Turid , Berzaghi Rodrigo , Martinez‐Zubiaurre Inigo 
Published: March 2024

AbstractBackgroundCancer‐associated fibroblasts (CAFs) consist of heterogeneous connective tissue cells and are often constituting the most abundant cell type in the tumor stroma. Radiation effects on tumor stromal components like CAFs in the context of radiation treatment is not well‐described.AimThis study explores potential changes induced by ionizing radiation (IR) on platelet‐derived growth factor (PDGF)/PDGFRs and transforming growth factor‐beta (TGF‐β)/TGFβRs signaling systems in CAFs.Methods and ResultsExperiments were carried out by employing primary cultures of human CAFs isolated from freshly resected non‐small cell lung carcinoma tumor tissues. CAF cultures from nine donors were treated with one high (1 × 18 Gy) or three fractionated (3 × 6 Gy) radiation doses. Alterations in expression levels of TGFβRII and PDGFRα/β induced by IR were analyzed by western blots and flow cytometry. In the presence or absence of cognate ligands, receptor activation was studied in nonirradiated and irradiated CAFs. Radiation exposure did not exert changes in expression of PDGF or TGF‐β receptors in CAFs. Additionally, IR alone was unable to trigger activation of either receptor. The radiation regimens tested did not affect PDGFRβ signaling in the presence of PDGF‐BB. In contrast, signaling via pSmad2/3 and pSmad1/5/8 appeared to be down‐regulated in irradiated CAFs after stimulation with TGF‐β, as compared with controls.ConclusionOur data demonstrate that IR by itself is insufficient to induce measurable changes in PDGF or TGF‐β receptor expression levels or to induce receptor activation in CAFs. However, in the presence of their respective ligands, exposure to radiation at certain doses appear to interfere with TGF‐β receptor signaling.
Phosphaarsenes – Combining Phospha‐ and Arsa‐Wittig‐Reagents
Authors: Beer Henrik , Siewert Jan‐Erik , Schröder Mirjam , Fischer Malte , Corzilius Björn , Hering‐Junghans Christian 
Published: March 2024

AbstractDipnictenes of the type RPn=PnR (Pn=P, As, Sb, Bi) can be viewed as dimers of the corresponding pnictinidenes R−Pn. Phosphanylidene‐ and arsanylidenephosphoranes (R−Pn(PMe3); Pn=P, As) have been shown to be versatile synthetic surrogates for the delivery of pnictinidene fragments. We now report that thermal treatment of 1 : 1 mixtures of R−P(PMe3) and R’−As(PMe3) gives access to arsaphosphenes of the type RP=AsR’. Three examples are presented and the properties and reactivity of Mes*P=AsDipTer (1) (Mes*=2,4,6‐tBu3‐C6H2; DipTer=2,6‐(2,6‐iPr2C6H3)2‐C6H3) were studied in detail. Solid state 31P NMR spectroscopy revealed a large 31P NMR chemical shift anisotropy with a span of ca. 920 ppm for 1 while computational methods were employed to investigate this pronounced magnetic deshielding of the P atom in 1. In the presence of the carbene IMe4 (IMe4=:C(MeNCMe)2) 1 is shown to be split into the corresponding NHC adducts Mes*P(IMe4) and DipTerAs(IMe4), which is additionally shown for diarsenes.
Multi‐azo Photoswitches for Improved Molecular Solar Thermal Energy Storage
Authors: Dong Dongfang , Li Tao 
Published: March 2024

AbstractMolecular solar thermal energy storage (MOST) based on photoisomerization represents a novel approach for the capture, conversion and storage of solar energy. Azo photoswitches can store energy by isomerization from their thermodynamically stable E isomers to higher energy metastable Z isomers. The energy density of azo photoswitches is crucial as it directly determines the storage capacity, but it is relatively low (160 J g−1). Therefore, enhancing the energy density through molecular structural design represents a central research focus in the field of MOST. A straightforward approach to enhance the energy density is to design multi‐azo photoswitches. This allows multiple azobenzene units to share a common framework while keeping the molecular weight as small as possible. In particular, when two azobenzene units are connected via a phenyl ring in a meta orientation, it facilitates efficient isomerization, thereby maximizing the energy density of the azo photoswitches (392 J g−1). This paper provides a brief overview of the development of multi‐azo photoswitches and highlights their outstanding performance as a MOST system. It also offers prospects for their future advancements in the field. We propose that, to further improve the energy density of multi‐azo photoswitches, one approach is to design wide spectrum of light photoisomerization of multi‐azo photoswitches. Additionally, introducing photo‐induced phase changes to multi‐azo photoswitches enables the simultaneous storage of both photon energy and ambient heat.
Multi‐metallic Layered Catalysts for Stable Electrochemical CO2 Reduction to Formate and Formic Acid
Authors: Nguyen Tu N. , Khiarak Behnam Nourmohammadi , Xu Zijun , Farzi Amirhossein , Sadaf Sharif Md. , Seifitokaldani Ali , Dinh Cao‐Thang 
Published: March 2024

AbstractElectrochemical CO2 reduction (ECR) to value‐added products such as formate/formic acid is a promising approach for CO2 mitigation. Practical ECR requires long‐term stability at industrially relevant reduction rates, which is challenging due to the rapid degradation of most catalysts at high current densities. Herein, we report the development of a bismuth (Bi) gas diffusion electrode on a polytetrafluoroethylene‐based electrically conductive silver (Ag) substrate (Ag@Bi), which exhibits high Faradaic efficiency (FE) for formate of over 90 % in 1 M KOH and 1 M KHCO3 electrolytes. The catalyst also shows high selectivity of formic acid above 85 % in 1 M NaCl catholyte, which has a bulk pH of 2–3 during ECR, at current densities up to 300 mA cm−2. In 1 M KHCO3 condition, Ag@Bi maintains formate FE above 90 % for at least 500 hours at the current density of 100 mA cm−2. We found that the Ag@Bi catalyst degrades over time due to the leaching of Bi in the NaCl catholyte. To overcome this challenge, we deposited a layer of Ag nanoparticles on the surface of Ag@Bi to form a multi‐layer Ag@Bi/Ag catalyst. This designed catalyst exhibits 300 hours of stability with FE for formic acid ≥70 % at 100 mA cm−2. Our work establishes a new strategy for achieving the operational longevity of ECR under wide pH conditions, which is critical for practical applications.
Energy optimized artificial hummingbird algorithm for routing in IoT‐based software‐defined WSN
Authors: Beniwal Rohit , Kumar Nitesh 
Published: March 2024

SummaryThe Internet of Things (IoT) has become widely used in applications such as smart homes, industrial automation, and transportation due to its affordable hardware and fast internet connectivity. However, the increase in IoT‐enabled gadgets, particularly those running on batteries or connected to other sources, is putting strain on the world's energy requirements. Therefore, this study focuses on a green routing solution for battery‐powered IoT‐enabled Software‐defined Wireless Sensor Networks (IoT‐SDWSN). Finding green solutions for IoT‐based networks to address this energy challenge has become crucial. This study focuses on developing a green routing solution for battery‐powered IoT‐SDWSN. Energy efficiency in IoT‐SDWSN is attained by the process of clustering nodes. The network is partitioned into small clusters, and a Control Node (CN) is set up by a Control Server (CS) to transmit the data packets sent by sensor nodes. Choosing a CN in these networks is a critical concern due to the substantial energy consumption involved in delivering data to the CS. This research focuses on the problem of energy‐efficient cluster routing in IoT‐based SD‐WSN. It introduces the Energy‐optimized Artificial Hummingbird Algorithm (EOAHA) as a green routing technique. EOAHA aims to extend the lifespan of IoT‐based SD‐WSNs by intelligently selecting (based on a new fitness function) CNs to distribute the network load and increase its overall longevity. To evaluate the performance of EOAHA, a comparative analysis is conducted against other state‐of‐the‐art algorithms. The results demonstrate that EOAHA outperforms these algorithms by a minimum of 13.5% in terms of network longevity.
Timely dying in dementia: Use patients' judgments and broaden the concept of suffering
Authors: Terman Stanley A. , Steinberg Karl E. , Hinerman Nathaniel 
Published: March 2024

AbstractPatients living with advanced dementia (PLADs) face several challenges to attain the goal of avoiding prolonged dying with severe suffering. One is how to determine when PLADs’ current suffering becomes severe enough to cease all life‐sustaining treatments, including withdrawing assistance with oral feeding and hydrating, a controversial order. This article broadens the concept of suffering by including suffering that cannot be observed contemporaneously and the suffering of loved ones. Four paradigm shifts operationalize these concepts. During advance care planning, patients can judge which future clinical conditions would cause severe suffering. To decide when to allow patients to die, treating physicians/providers only need to assess if patients have reached patients' previously judged, qualifying conditions. Questions: Will this protocol prevent PLADs’ prolonged dying with suffering? Deter early‐stage dementia patients from committing preemptive suicide? Sway decision‐making surrogates from withholding life‐sustaining treatments from patients with middle‐stage dementia? Provoke providers’ resistance to relinquish their traditional, unilateral authority to determine patients’ suffering?
Hydrologic remobilisation of tephra‐fall deposits: A sedimentological analysis throughout fluvio‐lacustrine systems of North‐West Patagonia
Authors: Losano Nahuel , Villarosa Gustavo , Beigt Débora , Amat Pablo , Cottet Julieta , Outes Valeria 
Published: March 2024

AbstractThis paper explores the response to Holocene ash inundation in different sub‐environments of two fluvio‐lacustrine systems, Las Piedritas and Totoral, focussing on the processes of volcaniclastic remobilisation. Sediment cores and outcrops were used to recognise three deposit types, noting how some differ from lahars, through sedimentological and stratigraphic analysis: (1) thick, laterally discontinuous, pumice‐dominated deposits occur overlying alluvial plain and lower terrace surfaces across both watersheds; (2) chaotic, extremely poorly sorted and matrix‐supported beds composed of both epiclastic and pyroclastic material occur as two conspicuous deposits at Las Piedritas outcrops, in a low‐gradient confined channel setting; and (3) layers with an exclusively pyroclastic composition and no flow sedimentary structures or fragment roundness were found draping each of the two chaotic intervals and intercalating with the background sediment in Las Piedritas prodelta. Thick pumice packages capping the floodplains resulted from the overflow of streams carrying a floating pumice load. Due to its positive buoyancy, the pumice is transported as a slowly moving overlying mantle without mixing with the streamflow. The disorganised pattern and poor sorting of the matrix‐rich polymictic beds are consistent with laminar, gravity‐driven, high‐concentration flows. They constitute secondary lahars, originating upstream from large run‐off processes that reworked a pyroclastic substrate. The lack of reworking features in the vitric‐rich units identified in the lake core retrieved from Las Piedritas prodelta, as well as the continuous and widespread occurrences of those interbedded in upstream outcrops, indicate an airfall origin. No reworked tephra unit is recognised in the prodelta sediment record, although various deposits from the hydrologic remobilisation of airfall tephra are found along the subaerial portion of both watersheds. Apparently, large amounts of flotation‐remobilised tephra were retained on the delta plain, while another considerable fraction would have been carried away from the creek mouth under the influence of dominant regional winds.