bluuebunny/crossref_metadata_2025_split huggingface dataset:
Selective C−H Halogenation of Alkenes and Alkynes Using Flavin‐Dependent Halogenases
Authors: Jiang Yuhua , Kim Ahram , Olive Cahmlo , Lewis Jared C. 
Published: January 2024

AbstractSingle component flavin‐dependent halogenases (FDHs) possess both flavin reductase and FDH activity in a single enzyme. We recently reported that the single component FDH AetF catalyzes site‐selective bromination and iodination of a variety of aromatic substrates and enantioselective bromolactonization and iodoetherification of styrenes bearing pendant carboxylic acid or alcohol substituents. Given this inherent reactivity and selectivity, we explored the utility of AetF as catalyst for alkene and alkyne C−H halogenation. We find that AetF catalyzes halogenation of a range of 1,1‐disubstituted styrenes, often with high stereoselectivity. Despite the utility of haloalkenes for cross‐coupling and other applications, accessing these compounds in a stereoselective manner typically requires functional group interconversion processes, and selective halogenation of 1,1′‐disubstituted olefins remains rare. We also establish that AetF and homologues of this enzyme can halogenate terminal alkynes. Mutagenesis studies and deuterium kinetic isotope effects are used to support a mechanistic proposal involving covalent catalysis for halogenation of unactivated alkynes by AetF homologues. These findings expand the scope of FDH catalysis and continue to show the unique utility of single component FDHs for biocatalysis.
π‐Radical Cascade to a Chiral Saddle‐Shaped Peropyrene
Authors: Bernhardt Annika , Čavlović Daniel , Mayländer Maximilian , Blacque Olivier , Cruz Carlos M. , Richert Sabine , Juríček Michal 
Published: January 2024

AbstractReactions of open‐shell molecular graphene fragments are typically thought of as undesired decomposition processes because they lead to the loss of desired features like π‐magnetism. Oxidative dimerization of phenalenyl to peropyrene shows, however, that these transformations hold promise as a synthetic tool for making complex structures via formation of multiple bonds and rings in a single step. Here, we explore the feasibility of using this “undesired” reaction of phenalenyl to build up strain and provide access to non‐planar polycyclic aromatic hydrocarbons. To this end, we designed and synthesized a biradical system with two phenalenyl units linked via a biphenylene backbone. The design facilitates an intramolecular cascade reaction to a helically twisted saddle‐shaped product, where the key transformations—ring‐closure and ring‐fusion—occur within one reaction. The negative curvature of the final peropyrene product, induced by the formed eight‐membered ring, was confirmed by single‐crystal X‐ray diffraction analysis and the helical twist was validated via resolution of the product's enantiomers that display circularly polarized luminescence and high configurational stability.
Spirobifluorene‐Based Porous Organic Salts: Their Porous Network Diversification and Construction of Chiral Helical Luminescent Structures
Authors: Okubo Kohei , Oka Kouki , Tsuchiya Keiho , Tomimoto Atsunori , Tohnai Norimitsu 
Published: January 2024

AbstractPorous organic salts (POSs) are organic porous materials assembled via charge‐assisted hydrogen bonds between strong acids and bases such as sulfonic acids and amines. To diversify the network topology of POSs and extend its functions, this study focused on using 4,4′,4′′,4′′′‐(9,9′‐spirobi[fluorene]‐2,2′,7,7′‐tetrayl)tetrabenzenesulfonic acid (spiroBPS), which is a tetrasulfonic acid comprising a square planar skeleton. The POS consisting of spiroBPS and triphenylmethylamine (TPMA) (spiroBPS/TPMA) was constructed from the two‐fold interpenetration of an orthogonal network with pts topology, which has not been reported in conventional POSs, owing to the shape of the spirobifluorene backbone. Furthermore, combining tris(4‐chlorophenyl)methylamine (TPMA‐Cl) and tris(4‐bromophenyl)methylamine (TPMA‐Br), which are bulkier than TPMA owing to the introduction of halogens at the p‐position of the phenyl groups with spiroBPS allows us to construct novel POSs (spiroBPS/TPMA‐Cl and spiroBPS/TPMA‐Br). These POSs were constructed from a chiral helical network with pth topology, which was induced by the steric hindrance between the halogens and the curved fluorene skeleton. Moreover, spiroBPS/TPMA‐Cl with pth topology exhibited circularly polarized luminescence (CPL) in the solid state, which has not been reported in hydrogen‐bonded organic frameworks (HOFs).
Chiral CpxRhodium(III)‐Catalyzed Enantioselective Aziridination of Unactivated Terminal Alkenes
Authors: Wang Juanjuan , Luo Mu‐Peng , Gu Yi‐Jie , Liu Yu‐Ying , Yin Qin , Wang Shou‐Guo 
Published: January 2024

AbstractChiral cyclopentadienyl‐rhodium(III) CpxRh(III) catalysis has been demonstrated to be competent for catalyzing highly enantioselective aziridination of challenging unactivated terminal alkenes and nitrene sources. The chiral CpxRh(III) catalysis system exhibited outstanding catalytic performance and wide functional group tolerance, yielding synthetically important and highly valuable chiral aziridines with good to excellent yields and enantioselectivities (up to 99 % yield, 93 % ee). This protocol presents a novel and effective strategy for synthesizing enantioenriched aziridines from simple alkenes. Various transformations were performed on the aziridine products, illustrating the versatility and synthetic potential of this protocol for constructing highly functionalized compounds.
Engineering Hydroxylase Activity, Selectivity, and Stability for a Scalable Concise Synthesis of a Key Intermediate to Belzutifan
Authors: Cheung‐Lee Wai Ling , Kolev Joshua N. , McIntosh John A. , Gil Agnieszka A. , Pan Weilan , Xiao Li , Velásquez Juan E. , Gangam Rekha , Winston Matthew S. , Li Shasha , Abe Kotoe , Alwedi Embarek , Dance Zachary E. X. , Fan Haiyang , Hiraga Kaori , Kim Jungchul , Kosjek Birgit , Le Diane N. , Marzijarani Nastaran Salehi , Mattern Keith , McMullen Jonathan P. , Narsimhan Karthik , Vikram Ajit , Wang Wei , Yan Jia‐Xuan , Yang Rong‐Sheng , Zhang Victoria , Zhong Wendy , DiRocco Daniel A. , Morris William J. , Murphy Grant S. , Maloney Kevin M. 
Published: January 2024

AbstractBiocatalytic oxidations are an emerging technology for selective C−H bond activation. While promising for a range of selective oxidations, practical use of enzymes catalyzing aerobic hydroxylation is presently limited by their substrate scope and stability under industrially relevant conditions. Here, we report the engineering and practical application of a non‐heme iron and α‐ketoglutarate‐dependent dioxygenase for the direct stereo‐ and regio‐selective hydroxylation of a non‐native fluoroindanone en route to the oncology treatment belzutifan, replacing a five‐step chemical synthesis with a direct enantioselective hydroxylation. Mechanistic studies indicated that formation of the desired product was limited by enzyme stability and product overoxidation, with these properties subsequently improved by directed evolution, yielding a biocatalyst capable of >15,000 total turnovers. Highlighting the industrial utility of this biocatalyst, the high‐yielding, green, and efficient oxidation was demonstrated at kilogram scale for the synthesis of belzutifan.
Palladium‐Catalyzed Deuteration of Arylketone Oxime Ethers
Authors: Wang Zhen‐Yu , Zhang Xu , Chen Wen‐Qing , Sun Guo‐Dong , Wang Xing , Tan Lin , Xu Hui , Dai Hui‐Xiong 
Published: January 2024

AbstractWe report herein the development of palladium‐catalyzed deacylative deuteration of arylketone oxime ethers. This protocol features excellent functional group tolerance, heterocyclic compatibility, and high deuterium incorporation levels. Regioselective deuteration of some biologically important drugs and natural products are showcased via Friedel–Crafts acylation and subsequent deacylative deuteration. Vicinal meta‐C−H bond functionalization (including fluorination, arylation, and alkylation) and para‐C−H bond deuteration of electro‐rich arenes are realized by using the ketone as both directing group and leaving group, which is distinct from aryl halide in conventional dehalogenative deuteration.
Preparation of thermally stable and flame‐retardant sugarcane bagasse‐ammonium dihydrogen phosphate/epoxy composites and their performance
Authors: Liu Shang‐Hao , Kuan Chen‐Feng , Ke Cing‐Yu , Shen Ming‐Yuan , Chiang Chin‐Lung 
Published: January 2024

AbstractEpoxy resin was often applied in fiber‐reinforced composite materials, adhesives, and encapsulation materials. However, epoxy was easily flammable and limited its usage in certain applications. The study recycled and reused agricultural waste sugarcane bagasse to prepare a halogen‐free bio‐based intumescent flame retardant and then mixed with epoxy resin to prepare a composite containing polymer with improved thermal properties and flame retardancy of the materials. The work followed the concept of circular economy and sustainability. Bagasse‐ammonium dihydrogen phosphate (ADP) flame retardant was added to an epoxy resin to prepare epoxy/bagasse‐ADP composites, an effective flame‐retarding composite material through hydrothermal method. Adding bagasse‐ADP increased the thermal stability and flame retardancy of the composite materials compared with that of pure epoxy. For the material with 30 wt% added bagasse‐ADP, the char yield was 32.3 wt%, which was 18.2 wt% higher than that of pure epoxy (14.1 wt%) through thermogravimetric analysis. In addition, the limiting oxygen index increased from 21% to 30%, and the UL‐94 classification improved from “Fail” to “V‐0.” This performance was attributed to the nitrogen, phosphorus, and silicon content of the flame retardant.
Compositae‐ParaLoss‐1272: A complementary sunflower‐specific probe set reduces paralogs in phylogenomic analyses of complex systems
Authors: Moore‐Pollard Erika R. , Jones Daniel S. , Mandel Jennifer R. 
Published: January 2024

AbstractPremiseA family‐specific probe set for sunflowers, Compositae‐1061, enables family‐wide phylogenomic studies and investigations at lower taxonomic levels, but may lack resolution at genus to species levels, especially in groups complicated by polyploidy and hybridization.MethodsWe developed a Hyb‐Seq probe set, Compositae‐ParaLoss‐1272, that targets orthologous loci in Asteraceae. We tested its efficiency across the family by simulating target enrichment sequencing in silico. Additionally, we tested its effectiveness at lower taxonomic levels in the historically complex genus Packera. We performed Hyb‐Seq with Compositae‐ParaLoss‐1272 for 19 Packera taxa that were previously studied using Compositae‐1061. The resulting sequences from each probe set, plus a combination of both, were used to generate phylogenies, compare topologies, and assess node support.ResultsWe report that Compositae‐ParaLoss‐1272 captured loci across all tested Asteraceae members, had less gene tree discordance, and retained longer loci than Compositae‐1061. Most notably, Compositae‐ParaLoss‐1272 recovered substantially fewer paralogous sequences than Compositae‐1061, with only ~5% of the recovered loci reporting as paralogous, compared to ~59% with Compositae‐1061.DiscussionGiven the complexity of plant evolutionary histories, assigning orthology for phylogenomic analyses will continue to be challenging. However, we anticipate Compositae‐ParaLoss‐1272 will provide improved resolution and utility for studies of complex groups and lower taxonomic levels in the sunflower family.
The redescription of Malerisaurus robinsonae (Archosauromorpha: Allokotosauria) from the Upper Triassic lower Maleri Formation, Pranhita‐Godavari Basin, India
Authors: Sengupta Saradee , Ezcurra Martín D. , Bandyopadhyay Saswati 
Published: January 2024

AbstractAllokotosauria, a clade of non‐archosauriform archosauromorphs with a broad diversity of body plans, plays a crucial role in better understanding the evolutionary history of early diverging stem‐archosaurs. Here we provide a detailed redescription of Malerisaurus robinsonae, a malerisaurine allokotosaur from the middle Carnian—lowermost Norian lower Maleri Formation, Pranhita‐Godavari Basin, India. The new anatomical information available from recently discovered and well‐preserved skeletons of various allokotosaurs, such as Azendohsaurus madagaskarensis, Shringasaurus indicus, Puercosuchus traverorum, and Malerisaurus‐like taxa, and their comparison with Malerisaurus robinsonae enriches our understanding of the anatomy of this species. To reassess the phylogenetic relationships of Malerisaurus robinsonae, we revised its scorings and included eight additional allokotosaurian species to the already most comprehensive phylogenetic dataset focused on Permo‐Triassic archosauromorphs. We modified 70 scorings for Malerisaurus robinsonae and the new analysis recovered this species at the base of Malerisaurinae and this group as the earliest branch of Azendohsauridae. Pamelaria dolichotrachela is found as the earliest diverging non‐malerisaurine azendohsaurid and sister taxon to the Shringasaurus indicus + Azendohsaurus spp. clade. Trilophosaurid interrelationships are well resolved, with Teraterpeton hrynewichorum, Coelodontognathus ricovi, and Rutiotomodon tytthos as their successive earliest‐branching species. The position of Anisodontosaurus greeri as a sister taxon to Variodens inopinatus bolsters long ghost lineages in the Late Triassic trilophosaurid record. A disparity analysis of tooth crown morphology shows that Allokotosauria is the most disparate Permo‐Triassic archosauromorph clade, exploring the almost complete range of basic crown morphologies. Trilophosaurids occupy an area of the dental morphospace unique among archosauromorphs.
Recent Advances in Hydrogenation of CO2 to CO with Heterogeneous Catalysts Through the RWGS Reaction
Authors: Zhang Wenting , Sun Jiashu , Wang Hongli , Cui Xinjiang 
Published: January 2024

AbstractWith the continuous increase in CO2 emissions, primarily from the combustion of coal and oil, the ecosystem faces a significant threat. Therefore, as an effective method to minimize the issue, the Reverse Water Gas Shift (RWGS) reaction which converts CO2 towards CO attracts much attention, is an environmentally‐friendly method to mitigate climate change and lessen dependence on fossil fuels. Nevertheless, the inherent thermodynamic stability and kinetic inertness of CO2 is a big challenge under mild conditions. In addition, it remains another fundamental challenge in RWGS reaction owing to CO selectivity issue caused by CO2 further hydrogenation towards CH4. Up till now, a series of catalysis systems have been developed for CO2 reduction reaction to produce CO. Herein, the research progress of the well‐performed heterogeneous catalysts for the RWGS reaction were summarized, including the catalyst design, catalytic performance and reaction mechanism. This review will provide insights into efficient utilization of CO2 and promote the development of RWGS reaction.
Brain glutathione and GABA+ levels in autistic children
Authors: Song Yulu , Hupfeld Kathleen E. , Davies‐Jenkins Christopher W. , Zöllner Helge J. , Murali‐Manohar Saipavitra , Mumuni Abdul Nashirudeen , Crocetti Deana , Yedavalli Vivek , Oeltzschner Georg , Alessi Natalie , Batschelett Mitchell A. , Puts Nicolaas A. J. , Mostofsky Stewart H. , Edden Richard A. E. 
Published: January 2024

AbstractAutism spectrum disorder (ASD) is a neurodevelopmental condition characterized by social communication challenges and repetitive behaviors. Altered neurometabolite levels, including glutathione (GSH) and gamma‐aminobutyric acid (GABA), have been proposed as potential contributors to the biology underlying ASD. This study investigated whether cerebral GSH or GABA levels differ between a cohort of children aged 8–12 years with ASD (n = 52) and typically developing children (TDC, n = 49). A comprehensive analysis of GSH and GABA levels in multiple brain regions, including the primary motor cortex (SM1), thalamus (Thal), medial prefrontal cortex (mPFC), and supplementary motor area (SMA), was conducted using single‐voxel HERMES MR spectroscopy at 3T. The results revealed no significant differences in cerebral GSH or GABA levels between the ASD and TDC groups across all examined regions. These findings suggest that the concentrations of GSH (an important antioxidant and neuromodulator) and GABA (a major inhibitory neurotransmitter) do not exhibit marked alterations in children with ASD compared to TDC. A statistically significant positive correlation was observed between GABA levels in the SM1 and Thal regions with ADHD inattention scores. No significant correlation was found between metabolite levels and hyper/impulsive scores of ADHD, measures of core ASD symptoms (ADOS‐2, SRS‐P) or adaptive behavior (ABAS‐2). While both GSH and GABA have been implicated in various neurological disorders, the current study provides valuable insights into the specific context of ASD and highlights the need for further research to explore other neurochemical alterations that may contribute to the pathophysiology of this complex disorder.
Preconditioning Operation of Membraneless Vanadium Micro Redox Flow Batteries
Authors: Oraá‐Poblete Beatriz , Perez‐Antolin Daniel , Maurice Ange A. , Palma Jesus , Kjeang Erik , Quintero Alberto E. 
Published: January 2024

AbstractInvited for this month's cover picture is the R&D Department of B5tec lead by Dr. Alberto Quintero. The cover picture shows the first membraneless micro flow battery prototype. Read the full text of the Research Article at 10.1002/batt.202300367.
The positioning tensions between early career teachers’ and mentors’ perceptions of the mentor role
Authors: Curtis Elizabeth , Nguyen Hoa Thi Mai , Larsen Ellen , Loughland Tony 
Published: January 2024

AbstractEarly career teacher (ECT) mentoring has never been so important with escalating levels of attrition reported in numerous countries, including Australia, the US and the UK. However, inconsistent understanding of what a mentor can or should do continues to compromise the ways in which early career teachers experience this support. While previous research has reported on mentors’ differing perspectives on their role, we take a unique approach to this issue. In this paper, we explore the ways in which both mentors and ECTs understand the mentor role. We argue that where mentor and ECT understandings are in tension, the productive outcomes of mentoring for both the mentor and ECT are undermined. Drawing on Positioning Theory we report findings from the thematic analysis of 31 online interviews with 16 mentors and 15 ECTs in Australia. We found that while ECTs and mentors hold some common positionings, some significant differences were noted. These findings highlight the need to extend opportunities to learn about the mentoring role to include ECTs.
Development of novel carbon‐based biomedical platforms for intervention in xenotoxicant‐induced Parkinson's disease onset
Authors: Kumar Jyotish , Varela‐Ramirez Armando , Narayan Mahesh 
Published: January 2024

AbstractChronic exposure to herbicides, weedicides, and pesticides is associated with the onset and progress of neurodegenerative disorders such as Parkinson's disease (PD), Alzheimer's disease (AD), and Amyotrophic Lateral Sclerosis (ALS). Here, we have investigated whether quinic‐ and chlorogenic‐acid‐derived Carbon Quantum Dots (QACQDs and ChACQDs, respectively) protect against a (pesticide) paraquat‐insult model of PD. Our results indicated that both types of CQDs intervened in the soluble‐to‐toxic transformation of the amyloid‐forming model protein Hen Egg White Lysozyme (HEWL). Furthermore, QACQDs and ChACQDs demonstrated antioxidant activity while remaining biocompatible in a human neuroblastoma‐derived cell line (SH‐SY5Y) up to 5 mg/ml and protected the cell line from the environmental neurotoxicant (paraquat). Importantly, both CQDs were found to protect dopaminergic neuronal ablation in a paraquat model of Parkinson's disease using the nematode C. elegans. Our results are significant because both plant‐derived organic acids cross the blood–brain barrier, making them attractive for developing CQD architectures. Furthermore, since the synthesis of these CQDs was performed using green chemistry methods from precursor acids that cross the BBB, these engineered bionanomaterial platforms are tantalizing candidates for preventing neurodegenerative disorders associated with exposure to environmental neurotoxicants.
In Situ Preparation of Dehydrodieugenol‐Loaded Silver Nanoparticles and their Antischistosomal Activity
Authors: Oliveira Larissa V. F. , Camilo Fernanda F. , Soares Marisi G. , Cajas Rayssa A. , Cirino Maria E. , de Moraes Josué , Lago João Henrique G. 
Published: January 2024

AbstractSchistosomiasis is a major neglected disease that imposes a substantial worldwide health burden, affecting approximately 250 million people globally. As praziquantel is the only available drug to treat schistosomiasis, there is a critical need to identify new anthelmintic compounds, particularly from natural sources. To enhance the activity of different natural products, one potential avenue involves its combination with silver nanoparticles (AgNP). Based on this approach, a one‐step green method for the in situ preparation of dehydrodieugenol (DHDG) by oxidation coupling reaction using silver and natural eugenol is presented. AgNP formation was confirmed by UV‐Vis spectroscopy due to the appearance of the surface plasmon resonance (SPR) band at 430 nm which is characteristic of silver nanoparticles. The nanoparticles were spherical with sizes in the range of 40 to 50 nm. Bioassays demonstrated that the silver nanoparticles loaded with DHDG exhibited significant anthelmintic activity against Schistosoma mansoni adult worms without toxicity to mammalian cells and an in vivo animal model (Caenorhabditis elegans), contributing to the development of new prototypes based on natural products for the treatment of schistosomiasis.