bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Review on Synthesis of Polyketide Natural Products and Polyketide Building Blocks Based on Hydroxy‐Directed Nitrile Oxide Cycloaddition Reaction
Authors: Kumari Megha , Dey Ashutosh , Khatravath Mahender 
Published: January 2025

AbstractHydroxy‐directed nitrile oxide cycloaddition represents an underexplored strategy, though it is offering the regio, enantio and diastereo selective methods for the formation of isoxazolidines as latent aldol products. This approach offering unique regio‐ and stereoselectivity in constructing complex polyketide frameworks, leveraging hydroxy groups as directing agents, has the potential to expand synthetic methodologies for diverse applications in organic and medicinal chemistry. This review article covers the synthetic reports of polyketide building blocks/ natural products involving Hydroxy‐directed nitrile oxide cycloaddition as the key reaction. We believe that summarizing these methods would grab the attention of chemists who are aware and can explore this unique methodology for the synthesis of complex known polyketide natural products.
Educational attainment, Aβ, tau, and structural brain reserve in Alzheimer's disease
Authors: Cai Yue , Fang Lili , Li Anqi , Yang Jie , Zhou Xin , He Zhengbo , Sun Pan , Wang Qingyong , Guo Tengfei ,   Alzheimer's Disease Neuroimaging Initiative
Published: January 2025

AbstractINTRODUCTIONAlzheimer's disease (AD) patients with higher educational attainment (EA) often exhibit better cognitive function. However, the relationship among EA status, AD pathology, structural brain reserve, and cognitive decline requires further investigation.METHODSWe compared cognitive performance across different amyloid beta (Aβ) positron emission tomography (A ±) statuses and EA levels (High EA/Low EA). We examined the effects of Aβ plaques, tau tangles, and gray matter volume (GMV) on the relationship between EA and domain‐specific cognitive decline.RESULTSA+/High‐EA individuals exhibited slower cognitive decline in global cognition and language domains than A+/Low‐EA individuals. This cognitive benefit was independently and synergistically explained by reduced AD pathology, including lower Aβ and tau burdens, as well as preserved GMV. Additionally, High‐EA individuals experienced a median delay of 1.9 years in the onset of significant brain atrophy among A+ individuals.DISCUSSIONThese findings highlight the independent and synergistic contributions of EA‐associated AD pathology and GMV alterations to longitudinal cognitive decline.Highlights
Alzheimer's disease (AD) individuals with high educational attainment (EA) show slower declines in global cognition and language.
EA‐related slower cognitive decline is linked to reduced tau and greater gray matter volume in AD.
AD individuals with high EA show a median 1.9 year delayed onset of brain atrophy.
Tuning the Acid Hardness Nature of Cu Catalyst for Selective Nitrate‐to‐Ammonia Electroreduction
Authors: Wang Ruhan , Jia Shunhan , Wu Limin , Zhang Libing , Song Xinning , Tan Xingxing , Zheng Chaofeng , Li Weixiang , Ma Xiaodong , Qian Qingli , Kang Xinchen , Zhu Qinggong , Sun Xiaofu , Han Buxing 
Published: January 2025

AbstractElectrocatalytic nitrate reduction reaction (NO3RR) in alkaline electrolyte presents a sustainable pathway for energy storage and green ammonia (NH3) synthesis. However, it remains challenging to obtain high activity and selectivity due to the limited protonation and/or desorption processes of key intermediates. Herein, we propose a strategy to regulate the acid hardness nature of Cu catalyst by introducing appropriate modifier. Using density functional theory calculations, we firstly identified that the BaO‐modified Cu showed optimal Gibbs free energies for key NO3RR steps, including the protonation of *NO and the desorption of *NH3. Experimentally, the BaO‐modified Cu catalyst exhibited 97.3 % Faradaic efficiency (FE) for NH3 with a yield rate of 356.9 mmol h−1 gcat−1. It could also maintain high activity across a wide range of applied potentials and nitrate substrate concentrations. Detailed experimental and theoretical studies revealed that the Ba species could modulate the local electronic states of Cu, enhance the electron transfer rate, and optimize the adsorption/protonation/desorption processes of the N‐containing intermediates, leading to the excellent catalytic performance for NO3−‐to‐NH3.
Electrochemical Cyclopropanation of Unactivated Alkenes with Methylene Compounds
Authors: Liu Min , Wang Yanwei , Gao Chao , Jia Jingpei , Zhu Zile , Qiu Youai 
Published: January 2025

AbstractCyclopropanes are prevalent in natural products, pharmaceuticals, and bioactive compounds, functioning as a significant structural motif. Although a series of methods have been developed for the construction of the cyclopropane skeleton, the development of a direct and efficient strategy for the rapid synthesis of cyclopropanes from bench‐stable starting materials with a broad substrate scope and functional group tolerance remains challenging and highly desirable. Herein, we present an electrochemical method for the direct cyclopropanation of unactivated alkenes using active methylene compounds. The strategy shows a broad substrate scope with a high level of functional group compatibility, as well as potential application as demonstrated by late‐stage cyclopropanation of complex molecules and drug derivatives. Further mechanistic investigations suggest that Cp2Fe (Fc) plays an essential role as an oxidative mediator in generating radicals from active methylene compounds.
Thermostable phospholipase C: A key to efficient and sustainable enzymatic oil degumming processes
Authors: Val Diego S. , Nardo Luisina Di , Marchisio Fiorela , Lacava Franco , Aguirre Andrés , Peiru Salvador , Castelli María Eugenia , Espariz Martín , Abriata Luciano A. , Menzella Hugo G. , Rasia Rodolfo M. 
Published: January 2025

AbstractPhospholipase C (PLC) enzymes play a pivotal role in the degumming process of edible oils, which is essential for producing high‐quality refined oils. The enzymatic degumming process, compared with conventional chemical methods, offers significant advantages including improved oil yield, reduced environmental impact, and lower operational costs. However, the industrial application of PLC enzymes is often hindered by their limited stability under harsh processing conditions. This has driven extensive research efforts toward engineering thermostable PLC variants that can withstand the high temperatures and harsh environments typical of oil refining processes. In this review, we explore the latest advancements in the application, design and optimization of thermostable PLC enzymes. We discuss the fundamental economic and ecological interest behind the goal of obtaining thermostable enzymes, and two approaches to the problem, namely the search for enzymes in thermophilic organisms and the design of new sequences with improved stability and activity parameters.
Facile Extraction and Salinization of Biotransferred 1,5‐Pentanediamine to Produce Purified Nylon 56 Salt
Authors: Huang Wanshu , Zhang Xiaoyue , Liu Shuo , Shen Bowen , You Shengping , Su Rongxin , Qi Wei , Wang Mengfan 
Published: January 2025

ABSTRACTIn this study, an extraction and salinization method was developed to treat the biotransferred 1,5‐pentanediamine (PDA) to achieve the purification of PDA as well as the production of high‐purity Nylon 56 salt. Further analysis showed that the Nylon 56 salt product with 99.6% purity and 95.11 g/L yield could be obtained by mixing 0.4 M n‐butanol solution of self‐produced PDA and n‐butanol solution of commercial adipic acid in an equimolar ratio and reacting for 2 h at 323.15 K, 250 rpm. By comparison, the physical properties, structure, and thermal stability of the Nylon 56 salts produced by this process were basically the same as those of the Nylon 56 salt prepared with commercial technical grade PDA. The Nylon 56 salts were all in the form of short rod‐shaped powder with initial polymerization and decomposition temperatures of 458.95 and 487.85 K, respectively. Therefore, this biotransferred PDA extraction–salinization coupling process omitted the distillation and dissolution steps of PDA, and the high‐quality Nylon 56 monomer was produced by crystallization in the solution. The process achieves efficient high‐purity production of Nylon 56 salt and provides a new idea for solving the problem of preparation and storage and transport safety of high‐purity PDA.
Crystallisation Based Deracemisation and Chiral Resolution of Small Molecules
Authors: Saseendran Abhay S. K. , Jayaraj Haritha , Kartha Kalathil Krishnan , Sarala Anjana Suseelan 
Published: January 2025

AbstractEnantiomeric separation of chiral molecules is pivotal for exploring fundamental questions about life‘s origin and various other scientific domains. Crystallisation is an important platform for the separation of chiral molecules, elegantly applied to many systems, for instance, the formation of conglomerates, where the enantiomers crystallise as separate phases. Many approaches have been proposed to explore crystallisation‐driven enantiomeric separation with fewer insights into the complex pathways associated with the separation processes. Controlling derecemisation or chiral resolution through crystallisation by applying mechanical forces, magnetic substrates, and seeds have attracted significant attention due to better outcomes. Despite these advancements, the mechanisms behind the separation of enantiomers using crystallisation as a tool, especially the delicate balance between kinetically and thermodynamically controlled pathways, are unclear, particularly for small organic molecules critical to pharmaceutical applications. This review aims to address many of these challenges, providing synthetic chemists with a deeper understanding of the role of crystallisation for innovative enantiomeric separation strategies.
Unveiling the Broad‐Spectrum Efficacy of Volatile Terpenes to Fight Against SARS‐COV‐2‐Associated Mucormycosis
Authors: Zahran Eman Maher , Elfoly Ethar , Elhamadany Eyad Y. , Hemied Muhammad S. , Elsayed Tarek A. , Hisham Mohamed , Abdelmohsen Usama Ramadan 
Published: January 2025

ABSTRACTMucormycosis, a life‐threatening fungal infection caused by Mucorales, affects immunocompromised patients, especially SARS‐CoV‐2 ones. Existing antifungal therapies, like amphotericin B, have serious health risks. The current study reviews the literature regarding an overview of SARS‐CoV‐2‐associated mucormycosis, along with different terpenes from diverse edible sources, such as basil, ginger, and clove, which are detected till June 2024. The antifungal potential of collected terpenes, their classifications, mechanisms of action, minimum inhibitory concentration (MIC) values, and future perspectives are discussed here. The search identified 89 fungicidal volatile terpenes, belonging to about 26 families, from which 45 were selected for further in silico analysis. The results highlighted oryzalexin B (60), oryzalexin D (62), carvacrol (4), mansorin B (66), muzigadial (86), and lubimin (80) as potential antifungal agents against lanosterol 14α‐demethylase, CotH3, and mucoricin as potential targets in Mucorales. CotH3 is crucial for activating GRP‐78, a host co‐receptor for ACE2, which is essential for SARS‐CoV‐2 pathogenesis. Additionally, carvacrol was in vitro investigated against Mucor racemosus via the agar diffusion method, giving an MIC value of 1 mg/mL, compared to 0.1 mg/mL of ketoconazole. This study suggests promising potential for volatile terpenes in combating SARS‐CoV‐2‐associated mucormycosis, with the need for further refined in vitro and in vivo studies to establish clinical efficacy.
Chemical Composition and Anti‐sickling Activity of the Essential Oil From the Leaves of Lantana Montevidensis (Spreng.) Briq (Verbenaceae) Growing Wild in the Western Region of Democratic Republic of Congo
Authors: Philippe Babady‐Bila , Dorothée Tshilanda‐Dinangayi , Damien Tshibangu Sha‐Tshibey , David Masengi Makondo , Giresse Kiasama N'kal , Carlos Kabengele Nkongolo , Jean‐Paul Ngbolua Koto te Nyiwa , Pius Mpiana Tshimankinda 
Published: January 2025

ABSTRACTLantana montevidensis (Spreng.) Briq. is a shrub native to South American countries. In Congolese traditional medicine, its leaves are used as herbal tea or in steam inhalation therapy for the treatment of respiratory disorders. The goal of this study was to determine the chemical composition and the anti‐sickling activity of the essential oil obtained from the leaves of this species growing wild in the Democratic Republic of Congo. Previous studies on the chemical composition of this species essential oil showed that it is mainly rich in sesquiterpene hydrocarbons such as (E)‐caryophyllene, germacrene‐D, (Z)‐caryophyllene, valencene, bicyclogermacrene, (E)‐nerolidol, β‐selinene, sabinene, γ‐terpinene, and β‐elemene in different ratios. The gas chromatography‐mass spectrometry analysis of our oil revealed that it is rather rich in monoterpenes, with geranial (24.13%), neral (17.73%), limonene (8.27%), γ‐terpinene (2.81%), p‐cymene (2.36%), geraniol (2.33%), nerol (1.52%), citronellol (1.37%), linalool (1.24), and carvone (1.20%) as major constituents. Germacrene D (4.21%), α‐elemol (3.53%), and β‐caryophyllene (1.08%) were the only main sesquiterpenes detected, besides 6‐methyl‐5‐hepten‐2‐one (3.51%). The Emmel test performed on this essential oil displayed a strong anti‐sickling activity at the concentration of 625 µg/mL.
Alternative and Sustainable Route to Explore a New Class of Amidines by Photochemical Synergistic Effect of Copper/Nitroxyl Radical Catalysis via Halogen‐Atom Transfer
Authors: Sivaraj Chandrasekaran , Gandhi Thirumanavelan 
Published: January 2025

AbstractAmidines are a vital class of bioactive compounds and often necessitate multiple components for their synthesis. Therefore, exploring efficient and sustainable methodologies for their synthesis is indispensable. Herein, we disclose an alternative and greener method for synthesizing an unexplored new class of amidines through the photochemical synergistic effect of copper/nitroxyl radical catalysis. This approach facilitates site‐selective radical amination of unactivated imine C(sp2)−H bond in C,N,N‐cyclic imines over favored selectivity via halogen‐atom transfer (XAT). This greener method ticks 11 out of 12 green chemistry metrics (GCM), effectively sidestepping the need for oxidants, bases, ligands, multistep processes, and harsh conditions, distinguishing it from conventional methods described in previous studies. Kinetic, spectroscopic, and computational tools have been employed to elucidate the synergistic effect of Cu/nitroxyl radical, the role of light, XAT, the influence of substituents, and the order of the reaction in the catalytic cycle.
α/β Conflicting Aromaticity Under the Microscope: Study of Pro‐Aromatic Radicals
Authors: Lago‐Saavedra Raúl , Pérez‐Juste Ignacio , Mandado Marcos 
Published: January 2025

AbstractThe aromaticity of a representative sample of pro‐aromatic radicals and its nitro, amino, hydroxyl and imine substituted derivatives has been analysed by means of multicenter delocalization indices (MCI) and nuclear‐independent chemical shifts (NICS). Because of their radical character, these compounds may exhibit conflicting α/β aromaticity, so that the contribution of α and β electrons to the MCI and NICS has been analysed separately and their values qualitatively interpreted in terms of the 2n+1/2n rule. All the monocyclic radicals investigated show conflicting α/β aromaticity. Thus, significant MCI values have been found for one of the spin components, whereas negligible values, even slightly negative, have been obtained for the other spin component. NICS indices confirm the aromatic character reflected by the MCIs and clearly show the antiaromatic or non‐aromatic character of the other spin components. The same has been found for the donor rings of the bicyclic pro‐aromatic radicals investigated, whereas all the fused benzene rings of these radicals show a clear aromatic character in both spin components. Substitutions at the donor carbon position by strong deactivating groups provoke a small increase of the aromatic character in the aromatic spin components and a significant decrease of the antiaromatic character in the antiaromatic spin components whereas activating groups have little effect.
Revealing the Surface Reconstruction on the High OER Catalytic Activity of Ni3S2
Authors: Ou Wen , Liu Donghua , Ye Xin , Cui Ningyi , Zhou Yecheng 
Published: January 2025

AbstractSluggish oxygen evolution reaction (OER) is a crucial part of water splitting and solar fuel generation, which limits their utilization. Ni3S2 is a promising OER catalyst, in which surface reconstruction is an important step to improve performance. In this study, DFT calculations were employed to investigate the effect of surface reconstruction on (001), (110), and (101) surfaces of Ni3S2 in alkaline OER. According to the Pourbaix diagram and surface free energy landscape, Ni3S2 is prone to transform into Ni oxides and (oxy) hydroxides under alkaline OER conditions. This process induces exposed S atoms to leach and O from the electrolyte to incorporate S sites, thereby lowering the Bader charge of *O and increasing
, and then decrease
, the free energy penalty of the potential determining step. In general, the surface reconstruction enhances the OER activity through S leaching and adjusting the coordination environment. We believe this work not only provides insights into the clarification of surface reconstruction, but also provides a valuable guideline for the further discovery of efficient TM‐based sulfides.
Low Latency Multikernel Polar Codes Using Approximate Processing Element
Authors: Nandini Jali , Muralidhar Pullakandam , Sreehari Rao Patri 
Published: January 2025

ABSTRACTPolar codes have become increasingly popular over the last few years and are currently adopted for the control channels in 5G wireless communication systems. However, the traditional polar codes use a (2 2) binary kernel, which limits codeword lengths to powers of 2. Multikernel polar codes were proposed to provide flexibility in terms of codeword lengths and are decoded using a successive cancellation (SC) decoder. This work presents the architecture of a low‐latency SC decoder based on an approximate technique, decoding 3 bits in a single clock cycle at the final stage. The processing elements of the decoder are synthesized using the Synopsys design compiler in CMOS 32‐nm technology. The processing element shows an average reduction of 53% in the area and 66.5% power savings. The proposed decoder's architecture is validated by FPGA implementation for a codeword length (768,384) and a code rate of 0.5. The proposed architecture demonstrates an effective hardware reduction technique with a significant decrease in the average latency of 51% and a minimal degradation in error performance, making it suitable for video broadcasting applications in 5G communications.
Peroral endoscopic myotomy for complex achalasia and the POEM difficulty score: An update
Authors: Ching Hui Yee Carmen , Youssef Michael , Woo Matthew , Bechara Robert 
Published: January 2025

AbstractObjectivesWe present an update on the (peroral endoscopic myotomy (POEM) difficulty score [PDS] by introducing a novel knife with waterjet functionality.MethodsThis is a retrospective review of patients who underwent POEM between May 2018 and July 2023 at the Kingston Health Sciences Center. Demographic and procedural variables were compared using descriptive and inferential statistics.ResultsOne hundred thirty‐nine consecutive POEMs were included in the study. Seventy‐four (56.7% male; aged 56.7 ± 16.5 years) complex achalasia (CA) and 65 (55.4% female; aged 47.3 ± 20.2 years) non‐CA POEM procedures were performed. PDS correlates moderately with procedural efficiency with a correlation coefficient of 0.595 (Spearman's p < 0.001). The mean efficiency for non‐CA was 3.3 ± 1.2 min/cm compared to CA as follows: type III 3.3 ± 1.3 min/cm; prior myotomy 5.3 ± 2.3 min/cm; ≧4 prior procedures 4.0 ± 1.7 min/cm; sigmoid type 5.2 ± 2.4 min/cm. The median PDS for non‐CA was 1 (1–5). In comparison, the median PDS for CA is as follows: type III 3 (2–4); prior myotomy 4 (3–5); ≧4 prior procedures 3 (1.25–4); sigmoid type 3 (2–4). PDS excluding the presence of spastic contractions correlated better with procedural velocity, with a correlation coefficient of 0.645 (Spearman's p < 0.001).ConclusionsPDS continues to moderately correlate with procedural efficiency using the novel knife. The presence of spastic contractions correlated poorly with procedural efficiency. Thus, it may be omitted in further studies.
Caregiver–Youth Agreement on the Nine‐Item Avoidant/Restrictive Food Intake Disorder Survey
Authors: Carmody Julia , Milliren Carly E. , Richmond Tracy K. , Crowley McGreggor , Eldredge Olivia , Jhe Grace B. , Freizinger Melissa , Bern Elana M. 
Published: January 2025

ABSTRACTBackgroundPatient and caregiver perspectives are critical in the evaluation of avoidant/restrictive food intake disorder (ARFID); however, little is understood about how caregiver and youth perceptions may differ. This study compared caregiver and youth reports among pediatric patients from an outpatient ARFID program.MethodsPatients (217 individuals with ARFID, aged 8–17) and their caregivers completed the Nine‐Item ARFID Screen (NIAS), a screening tool with parallel youth and caregiver report forms. The NIAS measures ARFID symptomatology across three presentations: sensory‐based selectivity (Picky Eating), low appetite/lack of interest in eating (Appetite), and fear of aversive consequences (Fear). Patient and caregiver NIAS scores were compared using t tests, and agreement was assessed via Pearson correlations. We examined the unadjusted bivariate association between patient age and caregiver–patient agreement.ResultsPatient mean age was 12.9 (SD = 2.5) and the majority were male (57.1%) and White, non‐Hispanic (68.2%) and with private insurance (88.0%). Caregivers reported higher ARFID symptomatology than patients themselves. Using caregiver scores compared to patients, a larger percentage was classified as all three presentations (23.5% vs. 11.5%) or combined selectivity and appetite (46.0% vs. 31.8%). Caregiver scores were higher on average regardless of patient age.DiscussionResults support obtaining both patient and caregiver reports whenever possible. Each perspective, as well as areas of discordance, may inform additional evaluation and treatment planning.