The construction of multirate rearrangeable network has long been an interesting problem. Of many results published, all were achieved on 3-stage Clos network. The monotone routing algorithm proposed by Hu et al.(2001...The construction of multirate rearrangeable network has long been an interesting problem. Of many results published, all were achieved on 3-stage Clos network. The monotone routing algorithm proposed by Hu et al.(2001) was also first applied to 3-stage Clos network. In this work, we adopt this algorithm and apply it to logd(N,m,p) networks. We first analyze the properties of logd(N,m,p) networks. Then we use monotone algorithm in logd(N,0,p) network. Furthermore we extend the result to construct multirate rearrangeable networks based on logd(N,m,p) network (1≤m≤n?1).展开更多
BACKGROUND Through deeper understanding of targetable driver mutations in non-small-cell lung cancer(NSCLC)over the past years,some patients with driver mutations have benefited from the targeted molecular therapies.A...BACKGROUND Through deeper understanding of targetable driver mutations in non-small-cell lung cancer(NSCLC)over the past years,some patients with driver mutations have benefited from the targeted molecular therapies.Although the anaplastic lymphoma kinase and BRAF mutations are not frequent subtypes in NSCLC,the availability of several targeted-drugs has been confirmed through a series of clinical trials.But little is clear about the proper strategy in rare BRAF G469A mutation,not to mention co-exhibition of anaplastic lymphoma kinase and BRAF G469A mutations,which is extremely rare in NSCLC.CASE SUMMARY We present a patient to stage IVA lung adenocarcinoma with coexisting echinoderm microtubule associated protein like-4 rearrangement and BRAF G469A mutation.She received several targeted drugs with unintended resistance and suffered from unbearable adverse events.CONCLUSION Due to the rarity of co-mutations,the case not only enriches the limited literature on NSCLC harbouring BRAF G469A and echinoderm microtubule associated protein like-4 mutations,but also suggests the efficacy and safety of specific multiple-drug therapy in such patients.展开更多
Uterine tumors resembling ovarian sex cord tumors(UTROSCTs)are characterized by an uncertain malignant potential and exhibit prominent sex cord-like differentiation.The purpose of this study was to comprehensively rev...Uterine tumors resembling ovarian sex cord tumors(UTROSCTs)are characterized by an uncertain malignant potential and exhibit prominent sex cord-like differentiation.The purpose of this study was to comprehensively review the clinicopathological characteristics of UTROSCTs and analyze eight cases of UTROSCTs treated at our hospital.We conducted an extensive review of the relevant literature and gathered pertinent data.In addition,we identified eight patients with UTROSCTs and analyzed their clinical and pathological features,diagnosis,treatment,and prognosis.Patients presented with symptoms such as abnormal vaginal bleeding or uterine mass detection.Surgical interventions varied,including total abdominal hysterectomy,bilateral salpingo-oophorectomy,and pelvic lymphadenectomy,with adjuvant therapy given to one patient.All eight patients are currently disease-free,with the longest follow-up period being nearly 10 years.Our systematic review of UTROSCTs summarized the clinical and pathological features and revealed several novel markers,including ESR1-NCOA2-3,GREB1-NCOA1-3,GREB1-CTNNB1,and GREB1-NR4A3.UTROSCTs are rare mesenchymal tumors with unclear histogenesis and uncertain malignant potential.Although our understanding of UTROSCTs remains incomplete,the promising findings and increasing availability of clinical data will contribute to the further understanding and development of this rare neoplasm.展开更多
In most Suzuki–Miyaura carbon-carbon cross-coupling reactions,the borabicyclo[3.3.1]nonane scaffold(9-BBN)only serves as an auxiliary facilitating the transmetalation step and thus is transformed into by-products.The...In most Suzuki–Miyaura carbon-carbon cross-coupling reactions,the borabicyclo[3.3.1]nonane scaffold(9-BBN)only serves as an auxiliary facilitating the transmetalation step and thus is transformed into by-products.There are rare examples where the 9-BBN derivatives serve as the potentially diverse C8 building blocks in cross-coupling reactions.Herein,we report a cobalt-catalyzed migratory carboncarbon cross-coupling reaction of the in situ formed 9-BBN ate complexes to afford diverse aryl-and alkyl-functionalized cyclooctenes.Preliminary mechanistic studies suggest the oxidation-induced cisbicyclo[3.3.0]oct-1-ylborane is the key intermediate in this migratory cross-coupling reaction,which promotes the development of other diverse migratory cross-coupling of borate complexes.展开更多
Lignin pyrolysis leads to the formation of diverse phenolic products that bear structural similarities to natural lignin,and the related mechanism has been widely explored based on the linkage cleavageinvolved reactio...Lignin pyrolysis leads to the formation of diverse phenolic products that bear structural similarities to natural lignin,and the related mechanism has been widely explored based on the linkage cleavageinvolved reactions.However,some unusual pyrolytic products exhibiting significant structure deviations from lignin,such as aldehydes,remain obscure in mechanism due to long-standing neglect of their formation pathways.The present work found the pivotal role of aryl migration,a special radical-mediated rearrangement process,in governing the formation of these atypical products for the first time.Herein,density functional theory calculations,electronic structure analyses,and pyrolysis experiments were combined to investigate rearrangement patterns and prerequisite structural characteristics of aryl migration by employing typical radicals derived from linkages and substituents of lignin as models.The results indicate that the radical with an unpaired electron located on the second atom of the aromatic side chain can undergo three-membered aryl 1,2-migration triggered by exo cyclization with the best superiority,determining the generation of aldehydes,alkenes,and other products through subsequent cleavage reactions.A clear correlation among the initial geometric and electronic structures of lignin,the patterns and types of aryl migration,the energy barriers,and the end products was established.This study contributes to systematically elucidating rearrangement mechanisms and constructing a more comprehensive lignin pyrolysis mechanism network.展开更多
Chromosomal rearrangements(CRs)often cause phenotypic variations.Although several major rearrangements have been identified in Triticeae,a comprehensive study of the order,timing,and breakpoints of CRs has not been co...Chromosomal rearrangements(CRs)often cause phenotypic variations.Although several major rearrangements have been identified in Triticeae,a comprehensive study of the order,timing,and breakpoints of CRs has not been conducted.Here,we reconstruct high-quality ancestral genomes for the most recent common ancestor(MRCA)of the Triticeae,and the MRCA of the wheat lineage(Triticum and Aegilops).The protogenes of MRCA of the Triticeae and the wheat lineage are 22,894 and 29,060,respectively,which were arranged in their ancestral order.By partitioning modern Triticeae chromosomes into sets of syntenic regions and linking each to the corresponding protochromosomes,we revisit the rye chromosome structural evolution and propose alternative evolutionary routes.The previously identified 4L/5L reciprocal translocation in rye and Triticum urartu is found to have occurred independently and is unlikely to be the result of chromosomal introgression following distant hybridization.We also clarify that the 4AL/7BS translocation in tetraploid wheat was a bidirectional rather than unidirectional translocation event.Lastly,we identify several breakpoints in protochromosomes that independently reoccur following Triticeae evolution,representing potential CR hotspots.This study demonstrates that these reconstructed ancestral genomes can serve as special comparative references and facilitate a better understanding of the evolution of structural rearrangements in Triticeae.展开更多
Herein,we report an iron-promoted carbonylation-rearrangement ofα-aminoaryl-tethered alkylidene cyclopropanes with CO_(2)to generate quinolinofuran derivatives.A variety of quinolinofuran derivatives are obtained in ...Herein,we report an iron-promoted carbonylation-rearrangement ofα-aminoaryl-tethered alkylidene cyclopropanes with CO_(2)to generate quinolinofuran derivatives.A variety of quinolinofuran derivatives are obtained in moderate to excellent yields,and two promising luminescent material molecules have been synthesized using the developed method.The Lewis acid Fe Cl_(3)was introduced into this reaction,which effectively promoted the ring opening and rearrangement of cyclopropanes.This reaction features a broad substrate scope,satisfactory functional group tolerance,facile scalability,and easy derivatization of the products.展开更多
Mitogenomes have been widely used in phylogenetic and taxonomic research,due to their maternal inheritance,accelerated evolutionary rates,compact circular structure,and the absence of introns.Although their utility is...Mitogenomes have been widely used in phylogenetic and taxonomic research,due to their maternal inheritance,accelerated evolutionary rates,compact circular structure,and the absence of introns.Although their utility is well-established,efficient mitogenome sequencing still poses a challenge for evolutionary studies.Here,we presented a novel hybridization capture protocol that enables high-fidelity sequencing of the complete mitogenome(16535 bp)of Odorrana nasuta.This genome exhibits typical anuran characteristics,including an A+T nucleotide bias(56.37%)and conserved gene composition.Notably,we identified a lineage-specific trnH transposition event that reorganizes the typical gene order into a unique trnH-trnL1-trnT-trnP-trnF cluster,which may be a potential synapomorphic trait for the genus Odorrana.Phylogenetic reconstruction using 13 protein-coding genes from 59 anuran species strongly supported the monophyly of Ranidae and its constituent genera(Odorrana,Rana,Lithobates,Amolops,Pelophylax,Glandirana),yet reveals the incongruence in the placement of Hylarana.The conflicting topologies observed for Hylarana and Glandirana across different studies highlight critical methodological limitations,including taxonomic sampling biases and data type dependency,which collectively compromise phylogenetic resolution.By integrating mitogenomic structure signatures with sequence-based phylogenies,this work advances our understanding of the systematics within Odorrana and highlights the need of multi-locus genomic datasets for resolving deep phylogenetic conflicts within Ranidae.展开更多
Low-dimensional hybrid metal halides exhibit broadband emission and high photoluminescence quantum yield(PLQY), making them promising candidates for the next-generation luminescent materials in lighting applications. ...Low-dimensional hybrid metal halides exhibit broadband emission and high photoluminescence quantum yield(PLQY), making them promising candidates for the next-generation luminescent materials in lighting applications. Here,the emission intensity of(C_(12)H_(24)O_(6))_(2)Na_(2)(H_(2)O)_(3)Cu_(4)I_(6) was strengthened between 9.3 GPa and 17.2 GPa, accompanied by the redshift of emission wavelength. The photoluminescence(PL) of Cu(Ⅰ)-based organometallic halides originates from multiple emission states, which are a metal-to-ligand charge transfer or a halide-to-ligand charge transfer(MLCT/HLCT)excited state and a cluster-centered(CC) excited state. MLCT/HLCT-related emission wavelength redshifts while CCrelated emission wavelength remains unchanged, indicating that the rearrangement of different emission states plays a critical role in the changes of luminescence wavelength. This study not only deepens the understanding of the influence of high pressure on(C_(12)H_(24)O_(6))_(2)Na_(2)(H_(2)O)_(3)Cu_(4)I_(6), but also provides valuable insights into the structure–property relationship of zero-dimensional Cu(Ⅰ)-based organometallic halides.展开更多
Interface modulation is an important pathway for highly efficient electromagnetic wave absorption.Herein,tailored interfaces between Fe_(3)O_(4)particles and the hexagonal-YFeO_(3)(h-YFeO_(3))framework were constructe...Interface modulation is an important pathway for highly efficient electromagnetic wave absorption.Herein,tailored interfaces between Fe_(3)O_(4)particles and the hexagonal-YFeO_(3)(h-YFeO_(3))framework were constructed via facile self-assembly.The resulting interfa-cial electron rearrangement at the heterojunction led to enhanced dielectric and magnetic loss synergy.Experimental results and density function theory(DFT)simulations demonstrate a transition in electrical properties from a half-metallic monophase to metallic Fe_(3)O_(4)/h-YFeO_(3)composites,emphasizing the advantages of the formed heterointerface.The transformation of electron behavior is also accompan-ied by a redistribution of electrons at the Fe_(3)O_(4)/h-YFeO_(3)heterojunction,leading to the accumulation of localized electrons around the Y-O-Fe band bridge,consequently enhancing the polarization.A minimum reflection loss of-34.0 dB can be achieved at 12.0 GHz and 2.0 mm thickness with an effective bandwidth of 3.3 GHz due to the abundant interfaces,enhanced polarization,and rational impedance.Thus,the synergistic effects endow the Fe_(3)O_(4)/h-YFeO_(3)composites with high performance and tunable functional properties for efficient electromagnetic absorption.展开更多
BACKGROUND Gastrointestinal stromal tumors(GISTs)are generally characterized by driver mutations in KIT or PDGFRA.However,the molecular landscape of wild-type GISTs remains complex,posing significant therapeutic chall...BACKGROUND Gastrointestinal stromal tumors(GISTs)are generally characterized by driver mutations in KIT or PDGFRA.However,the molecular landscape of wild-type GISTs remains complex,posing significant therapeutic challenges.Recent evidence has indicated alterations in FGFR2 as potential oncogenic drivers in patients with various cancers.However,the role of these drivers in GIST pathogenesis remains underexplored.CASE SUMMARY We retrospectively evaluated two patients with GIST,diagnosed between August 2021 and July 2022,harboring FGFR2 mutations through hybrid capture-based next-generation sequencing(NGS).We analyzed their clinicopathological characteristics,treatment response,and long-term follow-up data.Both patients,a 47-year-old man(case 1)and a 43-year-old woman(case 2),underwent successful surgical resection and received adjuvant imatinib therapy.They achieved sustained remission with a median follow-up of 28 months.Notably,the NGS revealed novel FGFR2 rearrangements,an FGFR2-CIT/intergenic-FGFR2 fusion in case 1 and FGFR2-CAMK2G/FGFR2-VCL fusions in case 2 without canonical KIT or PDGFRA mutations.Both patients exhibited a favorable response to standard imatinib treatment.CONCLUSION Our findings provided preliminary evidence that novel FGFR2 fusions might act as primary oncogenic drivers in a rare subset of KIT/PDGFRA wild-type GISTs.These cases highlight the importance for comprehensive genomic profiling and suggest that fibroblast growth factor receptor-targeted inhibitors could be a potential therapeutic strategy for advanced or imatinib-resistant diseases,warranting further investigation in larger cohorts.展开更多
A visible light-promoted fast photochemical Wolff rearrangement was developed toward synthesis ofα-substituted amides in continuous flow with the use of a photochemical oscillatory flow reactor(POFR).The control expe...A visible light-promoted fast photochemical Wolff rearrangement was developed toward synthesis ofα-substituted amides in continuous flow with the use of a photochemical oscillatory flow reactor(POFR).The control experiment indicates that a fast process of the Wolff rearrangement(<40 s)is involved.Notably,this protocol does not require excess use of any reactants,and the resultingα-substituted amides could be isolated by recrystallization in good to excellent yields.展开更多
The development of general and practical strategies toward the construction of medium-sized rings is still challenging in organic synthesis,especially for the multiple stereocenters control of substituted groups on th...The development of general and practical strategies toward the construction of medium-sized rings is still challenging in organic synthesis,especially for the multiple stereocenters control of substituted groups on the ring owing to the long distance between groups.Thus,stereoselective synthesis of multi-substituted ten-membered rings is attractive.Herein,a rapid assembly of various highly substituted ten-membered nitrogen heterocycles between two 1,3-dipoles through a tandem[3+3]cycloaddition/aza-Claisen rearrangement of N-vinyl-α,β-unsaturated nitrones and aza-oxyallyl or oxyallyl cations are disclosed.Products containing two or multiple stereocenters could be obtained in up to 96%yield with high regioselectivity and diastereoselectivity.Selective N-O bond cleavages of ten-membered nitrogen heterocycles lead to various novel 5,6,6-perifused benzofurans,bicyclo[4.4.0]or bicyclo[5.3.0]skeletons containing three or multiple continuous stereocenters in good yields and high diastereoselectivity.Biological tests show that the obtained ten-membered N-heterocycles and bicyclo[4.4.0]skeletons inhibited nitric oxide generation in LPS-stimulated RAW264.7 cells and might serve as good anti-inflammatory agents.展开更多
The Meinwald rearrangement has proven to be one of the most useful tools in organic synthesis.However,examples of asymmetric Meinwald rearrangements are quite scarce,and these reactions have so far been limited to the...The Meinwald rearrangement has proven to be one of the most useful tools in organic synthesis.However,examples of asymmetric Meinwald rearrangements are quite scarce,and these reactions have so far been limited to the use of chiral Br?nsted acids as catalysts.Here,we report a copper-catalyzed asymmetric cascade cyclization/Meinwald rearrangement reaction,allowing the practical and atom-economic synthesis of a range of chiral tricyclic pyrroles bearing a chiral oxa-quaternary carbon stereocenter in high yields and enantioselectivities.Thus,this protocol not only represents the first transition-metal-catalyzed enantioselective Meinwald rearrangement,but also constitutes the first example of asymmetric formal monocarbon insertion into C-O bond of ester.Moreover,theoretical calculations provide further evidence for this multiple cascade cyclization and elucidate the origin of enantioselectivity.展开更多
The radical difunctionalization of alkenes with sulfonyl bifunctional represents a powerful and straightforward approach to access functionalized alkane derivatives.However,both the mechanistic activation mode and the...The radical difunctionalization of alkenes with sulfonyl bifunctional represents a powerful and straightforward approach to access functionalized alkane derivatives.However,both the mechanistic activation mode and the substrate scopes of this type of radical difunctionalizations are still limited.We demonstrate herein a modular photoredox strategy for the difunctionalization of alkenes,employing arylsulfonyl acetate as the bifunctional reagent.This approach involves a radical addition/Smiles rearrangement cascade process,offering a robust alternative for the synthesis of valuableγ,γ-diaryl andγ-aryl esters.A complementary oxidative bifunctional reagents activation mode is identified to govern the radical cascade reactions,facilitating the simultaneous incorporation of aryl and carboxylate-bearing alkyl groups into the alkenes with excellent diastereoselectivity.Noteworthy features of this method include mild reaction conditions,organophotocatalysis,high atom-and step-economy,excellent functional group compatibility and great structural diversity.展开更多
Genome rearrangement is an important process that leads to genetic diversity,including mutation-related insertions,deletions,or inversions in the genome[1,2].
An efficient method for the preparation of 2-deoxy-glycopyranosides was developed by using 2,3-anhydrothioglycosides as the glycosylating agents.The reaction proceeded by the Cu(OTf)_2-mediated rearrangement of 2,3-an...An efficient method for the preparation of 2-deoxy-glycopyranosides was developed by using 2,3-anhydrothioglycosides as the glycosylating agents.The reaction proceeded by the Cu(OTf)_2-mediated rearrangement of 2,3-anhydrothiosugars.And high anomeric stereoselectivity was achieved.The disclosed methodology may find applications in the preparation of many biologically important 2-deoxy-glycosides.展开更多
Male infertility might be clearly associated with aberrant DNA methylation patterns in human spermatozoa. An association between oxidative stress and the global methylation status of the sperm genome has also been sug...Male infertility might be clearly associated with aberrant DNA methylation patterns in human spermatozoa. An association between oxidative stress and the global methylation status of the sperm genome has also been suggested. The aim of the present study was to determine whether the global sperm DNA methylation status was affected in the spermatozoa of carriers of chromosome structural aberrations. The relationships between the 5-methylcytosine （msC） levels in spermatozoa and chromatin integrity status were evaluated. The study patients comprised male carriers of chromosome structural aberrations with reproductive failure （n = 24）, and the controls comprised normozoospermic sperm volunteers （n = 23）. The global msC level was measured using thin-layer chromatography （TLC） and immunofluorescence （IF） techniques. The sperm chromatin integrity was assessed using aniline blue （AB） staining and TUNEL assay. The mean msC levels were similar between the investigated chromosome structural aberrations carriers （P） and controls （K）. However, sperm chromatin integrity tests revealed significantly higher values in chromosomal rearrangement carriers than in controls （P 〈 0.05）. Although the potential relationship between sperm chromatin integrity status and sperm DNA fragmentation and the msC level juxtaposed in both analyzed groups （P vs K） was represented in a clearly opposite manner, the low chromatin integrity might be associated with the high hypomethylation status of the sperm DNA observed in carriers of chromosome structural aberrations.展开更多
基金Project (No. 10371028) supported by the National Natural ScienceFoundation of China
文摘The construction of multirate rearrangeable network has long been an interesting problem. Of many results published, all were achieved on 3-stage Clos network. The monotone routing algorithm proposed by Hu et al.(2001) was also first applied to 3-stage Clos network. In this work, we adopt this algorithm and apply it to logd(N,m,p) networks. We first analyze the properties of logd(N,m,p) networks. Then we use monotone algorithm in logd(N,0,p) network. Furthermore we extend the result to construct multirate rearrangeable networks based on logd(N,m,p) network (1≤m≤n?1).
基金Supported by the Medical Education Collaborative Innovation Fund of Jiangsu University,No.JDY2022015。
文摘BACKGROUND Through deeper understanding of targetable driver mutations in non-small-cell lung cancer(NSCLC)over the past years,some patients with driver mutations have benefited from the targeted molecular therapies.Although the anaplastic lymphoma kinase and BRAF mutations are not frequent subtypes in NSCLC,the availability of several targeted-drugs has been confirmed through a series of clinical trials.But little is clear about the proper strategy in rare BRAF G469A mutation,not to mention co-exhibition of anaplastic lymphoma kinase and BRAF G469A mutations,which is extremely rare in NSCLC.CASE SUMMARY We present a patient to stage IVA lung adenocarcinoma with coexisting echinoderm microtubule associated protein like-4 rearrangement and BRAF G469A mutation.She received several targeted drugs with unintended resistance and suffered from unbearable adverse events.CONCLUSION Due to the rarity of co-mutations,the case not only enriches the limited literature on NSCLC harbouring BRAF G469A and echinoderm microtubule associated protein like-4 mutations,but also suggests the efficacy and safety of specific multiple-drug therapy in such patients.
文摘Uterine tumors resembling ovarian sex cord tumors(UTROSCTs)are characterized by an uncertain malignant potential and exhibit prominent sex cord-like differentiation.The purpose of this study was to comprehensively review the clinicopathological characteristics of UTROSCTs and analyze eight cases of UTROSCTs treated at our hospital.We conducted an extensive review of the relevant literature and gathered pertinent data.In addition,we identified eight patients with UTROSCTs and analyzed their clinical and pathological features,diagnosis,treatment,and prognosis.Patients presented with symptoms such as abnormal vaginal bleeding or uterine mass detection.Surgical interventions varied,including total abdominal hysterectomy,bilateral salpingo-oophorectomy,and pelvic lymphadenectomy,with adjuvant therapy given to one patient.All eight patients are currently disease-free,with the longest follow-up period being nearly 10 years.Our systematic review of UTROSCTs summarized the clinical and pathological features and revealed several novel markers,including ESR1-NCOA2-3,GREB1-NCOA1-3,GREB1-CTNNB1,and GREB1-NR4A3.UTROSCTs are rare mesenchymal tumors with unclear histogenesis and uncertain malignant potential.Although our understanding of UTROSCTs remains incomplete,the promising findings and increasing availability of clinical data will contribute to the further understanding and development of this rare neoplasm.
基金supported by the National Natural Science Foundation of China(No.22171046)the Hundred-Talent Project of Fujian(No.50021113)Fuzhou University(No.0480-00489503)。
文摘In most Suzuki–Miyaura carbon-carbon cross-coupling reactions,the borabicyclo[3.3.1]nonane scaffold(9-BBN)only serves as an auxiliary facilitating the transmetalation step and thus is transformed into by-products.There are rare examples where the 9-BBN derivatives serve as the potentially diverse C8 building blocks in cross-coupling reactions.Herein,we report a cobalt-catalyzed migratory carboncarbon cross-coupling reaction of the in situ formed 9-BBN ate complexes to afford diverse aryl-and alkyl-functionalized cyclooctenes.Preliminary mechanistic studies suggest the oxidation-induced cisbicyclo[3.3.0]oct-1-ylborane is the key intermediate in this migratory cross-coupling reaction,which promotes the development of other diverse migratory cross-coupling of borate complexes.
基金supported by the National Natural Science Foundation of China,China(52436009,52276189)the Postdoctoral Fellowship Program of CPSF,China(GZB20230207)the Fundamental Research Funds for the Central Universities,China(2024JC001,2024MS087)。
文摘Lignin pyrolysis leads to the formation of diverse phenolic products that bear structural similarities to natural lignin,and the related mechanism has been widely explored based on the linkage cleavageinvolved reactions.However,some unusual pyrolytic products exhibiting significant structure deviations from lignin,such as aldehydes,remain obscure in mechanism due to long-standing neglect of their formation pathways.The present work found the pivotal role of aryl migration,a special radical-mediated rearrangement process,in governing the formation of these atypical products for the first time.Herein,density functional theory calculations,electronic structure analyses,and pyrolysis experiments were combined to investigate rearrangement patterns and prerequisite structural characteristics of aryl migration by employing typical radicals derived from linkages and substituents of lignin as models.The results indicate that the radical with an unpaired electron located on the second atom of the aromatic side chain can undergo three-membered aryl 1,2-migration triggered by exo cyclization with the best superiority,determining the generation of aldehydes,alkenes,and other products through subsequent cleavage reactions.A clear correlation among the initial geometric and electronic structures of lignin,the patterns and types of aryl migration,the energy barriers,and the end products was established.This study contributes to systematically elucidating rearrangement mechanisms and constructing a more comprehensive lignin pyrolysis mechanism network.
基金CAs Youth Interdisciplinary Team(JCTD-2022-06)the National Nature Science Foundation of China(31870209).
文摘Chromosomal rearrangements(CRs)often cause phenotypic variations.Although several major rearrangements have been identified in Triticeae,a comprehensive study of the order,timing,and breakpoints of CRs has not been conducted.Here,we reconstruct high-quality ancestral genomes for the most recent common ancestor(MRCA)of the Triticeae,and the MRCA of the wheat lineage(Triticum and Aegilops).The protogenes of MRCA of the Triticeae and the wheat lineage are 22,894 and 29,060,respectively,which were arranged in their ancestral order.By partitioning modern Triticeae chromosomes into sets of syntenic regions and linking each to the corresponding protochromosomes,we revisit the rye chromosome structural evolution and propose alternative evolutionary routes.The previously identified 4L/5L reciprocal translocation in rye and Triticum urartu is found to have occurred independently and is unlikely to be the result of chromosomal introgression following distant hybridization.We also clarify that the 4AL/7BS translocation in tetraploid wheat was a bidirectional rather than unidirectional translocation event.Lastly,we identify several breakpoints in protochromosomes that independently reoccur following Triticeae evolution,representing potential CR hotspots.This study demonstrates that these reconstructed ancestral genomes can serve as special comparative references and facilitate a better understanding of the evolution of structural rearrangements in Triticeae.
基金the financial support from the National Natural Science Foundation of China(Nos.21801025,22225106)Natural Science Foundation of Sichuan Province(No.2022NSFSC0200)Sichuan Science and Technology Program(No.MZGC20230100)。
文摘Herein,we report an iron-promoted carbonylation-rearrangement ofα-aminoaryl-tethered alkylidene cyclopropanes with CO_(2)to generate quinolinofuran derivatives.A variety of quinolinofuran derivatives are obtained in moderate to excellent yields,and two promising luminescent material molecules have been synthesized using the developed method.The Lewis acid Fe Cl_(3)was introduced into this reaction,which effectively promoted the ring opening and rearrangement of cyclopropanes.This reaction features a broad substrate scope,satisfactory functional group tolerance,facile scalability,and easy derivatization of the products.
基金the National Natural Science Foundation of China(NSFC)to Zhuo CHEN(Grant Nos.32270440 and 31601848)and Xiaohong CHEN(Grant No.U21A20192).
文摘Mitogenomes have been widely used in phylogenetic and taxonomic research,due to their maternal inheritance,accelerated evolutionary rates,compact circular structure,and the absence of introns.Although their utility is well-established,efficient mitogenome sequencing still poses a challenge for evolutionary studies.Here,we presented a novel hybridization capture protocol that enables high-fidelity sequencing of the complete mitogenome(16535 bp)of Odorrana nasuta.This genome exhibits typical anuran characteristics,including an A+T nucleotide bias(56.37%)and conserved gene composition.Notably,we identified a lineage-specific trnH transposition event that reorganizes the typical gene order into a unique trnH-trnL1-trnT-trnP-trnF cluster,which may be a potential synapomorphic trait for the genus Odorrana.Phylogenetic reconstruction using 13 protein-coding genes from 59 anuran species strongly supported the monophyly of Ranidae and its constituent genera(Odorrana,Rana,Lithobates,Amolops,Pelophylax,Glandirana),yet reveals the incongruence in the placement of Hylarana.The conflicting topologies observed for Hylarana and Glandirana across different studies highlight critical methodological limitations,including taxonomic sampling biases and data type dependency,which collectively compromise phylogenetic resolution.By integrating mitogenomic structure signatures with sequence-based phylogenies,this work advances our understanding of the systematics within Odorrana and highlights the need of multi-locus genomic datasets for resolving deep phylogenetic conflicts within Ranidae.
基金Project supported by the National Key R&D Program of China (Grant No. 2023YFA1406200)the National Natural Science Foundation of China (Grant Nos. 12174144 and 12474009)the Graduate Innovation Fund of Jilin University (Grant No. 2024CX201)。
文摘Low-dimensional hybrid metal halides exhibit broadband emission and high photoluminescence quantum yield(PLQY), making them promising candidates for the next-generation luminescent materials in lighting applications. Here,the emission intensity of(C_(12)H_(24)O_(6))_(2)Na_(2)(H_(2)O)_(3)Cu_(4)I_(6) was strengthened between 9.3 GPa and 17.2 GPa, accompanied by the redshift of emission wavelength. The photoluminescence(PL) of Cu(Ⅰ)-based organometallic halides originates from multiple emission states, which are a metal-to-ligand charge transfer or a halide-to-ligand charge transfer(MLCT/HLCT)excited state and a cluster-centered(CC) excited state. MLCT/HLCT-related emission wavelength redshifts while CCrelated emission wavelength remains unchanged, indicating that the rearrangement of different emission states plays a critical role in the changes of luminescence wavelength. This study not only deepens the understanding of the influence of high pressure on(C_(12)H_(24)O_(6))_(2)Na_(2)(H_(2)O)_(3)Cu_(4)I_(6), but also provides valuable insights into the structure–property relationship of zero-dimensional Cu(Ⅰ)-based organometallic halides.
基金supported by the National Natural Science Foundation of China(Nos.52122106 and 52027802)the“Pioneer”Research and Development Program of Zhejiang Province,China(No.2022C01230)+2 种基金the Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering,China(No.2021SZ-FR005)the Space Application System of China Manned Space Program(No.KJZ-YY-NCL03)the opening fund of Key Laboratory of Rare Earths,Chinese Academy of Sciences。
文摘Interface modulation is an important pathway for highly efficient electromagnetic wave absorption.Herein,tailored interfaces between Fe_(3)O_(4)particles and the hexagonal-YFeO_(3)(h-YFeO_(3))framework were constructed via facile self-assembly.The resulting interfa-cial electron rearrangement at the heterojunction led to enhanced dielectric and magnetic loss synergy.Experimental results and density function theory(DFT)simulations demonstrate a transition in electrical properties from a half-metallic monophase to metallic Fe_(3)O_(4)/h-YFeO_(3)composites,emphasizing the advantages of the formed heterointerface.The transformation of electron behavior is also accompan-ied by a redistribution of electrons at the Fe_(3)O_(4)/h-YFeO_(3)heterojunction,leading to the accumulation of localized electrons around the Y-O-Fe band bridge,consequently enhancing the polarization.A minimum reflection loss of-34.0 dB can be achieved at 12.0 GHz and 2.0 mm thickness with an effective bandwidth of 3.3 GHz due to the abundant interfaces,enhanced polarization,and rational impedance.Thus,the synergistic effects endow the Fe_(3)O_(4)/h-YFeO_(3)composites with high performance and tunable functional properties for efficient electromagnetic absorption.
文摘BACKGROUND Gastrointestinal stromal tumors(GISTs)are generally characterized by driver mutations in KIT or PDGFRA.However,the molecular landscape of wild-type GISTs remains complex,posing significant therapeutic challenges.Recent evidence has indicated alterations in FGFR2 as potential oncogenic drivers in patients with various cancers.However,the role of these drivers in GIST pathogenesis remains underexplored.CASE SUMMARY We retrospectively evaluated two patients with GIST,diagnosed between August 2021 and July 2022,harboring FGFR2 mutations through hybrid capture-based next-generation sequencing(NGS).We analyzed their clinicopathological characteristics,treatment response,and long-term follow-up data.Both patients,a 47-year-old man(case 1)and a 43-year-old woman(case 2),underwent successful surgical resection and received adjuvant imatinib therapy.They achieved sustained remission with a median follow-up of 28 months.Notably,the NGS revealed novel FGFR2 rearrangements,an FGFR2-CIT/intergenic-FGFR2 fusion in case 1 and FGFR2-CAMK2G/FGFR2-VCL fusions in case 2 without canonical KIT or PDGFRA mutations.Both patients exhibited a favorable response to standard imatinib treatment.CONCLUSION Our findings provided preliminary evidence that novel FGFR2 fusions might act as primary oncogenic drivers in a rare subset of KIT/PDGFRA wild-type GISTs.These cases highlight the importance for comprehensive genomic profiling and suggest that fibroblast growth factor receptor-targeted inhibitors could be a potential therapeutic strategy for advanced or imatinib-resistant diseases,warranting further investigation in larger cohorts.
基金financial support from the National Natural Science Foundation of China(No.22208279)Financial support from the Fuzhou University(No.0041/511095)。
文摘A visible light-promoted fast photochemical Wolff rearrangement was developed toward synthesis ofα-substituted amides in continuous flow with the use of a photochemical oscillatory flow reactor(POFR).The control experiment indicates that a fast process of the Wolff rearrangement(<40 s)is involved.Notably,this protocol does not require excess use of any reactants,and the resultingα-substituted amides could be isolated by recrystallization in good to excellent yields.
基金the National Natural Science Foundation of China(No.22071035)the Natural Science Foundation of Guangxi(Nos.2023GXNSFDA026025,2022GXNSFBA035494)+2 种基金Guangxi Minzu University Scientific Research Funds for Talent Introduction(2022KJQD14)the Student Innovation Training Program(No.202310602014)are greatly appreciated.
文摘The development of general and practical strategies toward the construction of medium-sized rings is still challenging in organic synthesis,especially for the multiple stereocenters control of substituted groups on the ring owing to the long distance between groups.Thus,stereoselective synthesis of multi-substituted ten-membered rings is attractive.Herein,a rapid assembly of various highly substituted ten-membered nitrogen heterocycles between two 1,3-dipoles through a tandem[3+3]cycloaddition/aza-Claisen rearrangement of N-vinyl-α,β-unsaturated nitrones and aza-oxyallyl or oxyallyl cations are disclosed.Products containing two or multiple stereocenters could be obtained in up to 96%yield with high regioselectivity and diastereoselectivity.Selective N-O bond cleavages of ten-membered nitrogen heterocycles lead to various novel 5,6,6-perifused benzofurans,bicyclo[4.4.0]or bicyclo[5.3.0]skeletons containing three or multiple continuous stereocenters in good yields and high diastereoselectivity.Biological tests show that the obtained ten-membered N-heterocycles and bicyclo[4.4.0]skeletons inhibited nitric oxide generation in LPS-stimulated RAW264.7 cells and might serve as good anti-inflammatory agents.
基金financial support from the National Natural Science Foundation of China(Nos.22125108,22101238,22331004 and 22121001)Yunnan Fundamental Research Project(No.202401CF070024)+2 种基金Natural Science Foundation of Jiangsu Province(No.BK20211059)the Project of Science and Technology of Xuzhou Government(No.KC22080)NFFTBS(No.J1310024)。
文摘The Meinwald rearrangement has proven to be one of the most useful tools in organic synthesis.However,examples of asymmetric Meinwald rearrangements are quite scarce,and these reactions have so far been limited to the use of chiral Br?nsted acids as catalysts.Here,we report a copper-catalyzed asymmetric cascade cyclization/Meinwald rearrangement reaction,allowing the practical and atom-economic synthesis of a range of chiral tricyclic pyrroles bearing a chiral oxa-quaternary carbon stereocenter in high yields and enantioselectivities.Thus,this protocol not only represents the first transition-metal-catalyzed enantioselective Meinwald rearrangement,but also constitutes the first example of asymmetric formal monocarbon insertion into C-O bond of ester.Moreover,theoretical calculations provide further evidence for this multiple cascade cyclization and elucidate the origin of enantioselectivity.
基金the National Natural Science Foundation of China(No.21901199)National Training Program of Innovation and Entrepreneurship for Undergraduates(No.S202310698011)Xi’an Jiaotong University(No.7121192002)for financial support.
文摘The radical difunctionalization of alkenes with sulfonyl bifunctional represents a powerful and straightforward approach to access functionalized alkane derivatives.However,both the mechanistic activation mode and the substrate scopes of this type of radical difunctionalizations are still limited.We demonstrate herein a modular photoredox strategy for the difunctionalization of alkenes,employing arylsulfonyl acetate as the bifunctional reagent.This approach involves a radical addition/Smiles rearrangement cascade process,offering a robust alternative for the synthesis of valuableγ,γ-diaryl andγ-aryl esters.A complementary oxidative bifunctional reagents activation mode is identified to govern the radical cascade reactions,facilitating the simultaneous incorporation of aryl and carboxylate-bearing alkyl groups into the alkenes with excellent diastereoselectivity.Noteworthy features of this method include mild reaction conditions,organophotocatalysis,high atom-and step-economy,excellent functional group compatibility and great structural diversity.
基金supported by grants(92168103,32171417,2019CXJQ01)from the National Nature Science Foundation of China,Shanghai Municipal GovernmentPeak Disciplines(Type IV)of Institutions of Higher Learning in Shanghai.
文摘Genome rearrangement is an important process that leads to genetic diversity,including mutation-related insertions,deletions,or inversions in the genome[1,2].
基金National Natural Science Foundation of China (Grant No.20732001)Ministry of Science and Technology of China(Grant No.2009ZX09501-011).
文摘An efficient method for the preparation of 2-deoxy-glycopyranosides was developed by using 2,3-anhydrothioglycosides as the glycosylating agents.The reaction proceeded by the Cu(OTf)_2-mediated rearrangement of 2,3-anhydrothiosugars.And high anomeric stereoselectivity was achieved.The disclosed methodology may find applications in the preparation of many biologically important 2-deoxy-glycosides.
文摘Male infertility might be clearly associated with aberrant DNA methylation patterns in human spermatozoa. An association between oxidative stress and the global methylation status of the sperm genome has also been suggested. The aim of the present study was to determine whether the global sperm DNA methylation status was affected in the spermatozoa of carriers of chromosome structural aberrations. The relationships between the 5-methylcytosine （msC） levels in spermatozoa and chromatin integrity status were evaluated. The study patients comprised male carriers of chromosome structural aberrations with reproductive failure （n = 24）, and the controls comprised normozoospermic sperm volunteers （n = 23）. The global msC level was measured using thin-layer chromatography （TLC） and immunofluorescence （IF） techniques. The sperm chromatin integrity was assessed using aniline blue （AB） staining and TUNEL assay. The mean msC levels were similar between the investigated chromosome structural aberrations carriers （P） and controls （K）. However, sperm chromatin integrity tests revealed significantly higher values in chromosomal rearrangement carriers than in controls （P 〈 0.05）. Although the potential relationship between sperm chromatin integrity status and sperm DNA fragmentation and the msC level juxtaposed in both analyzed groups （P vs K） was represented in a clearly opposite manner, the low chromatin integrity might be associated with the high hypomethylation status of the sperm DNA observed in carriers of chromosome structural aberrations.
