Herein, we develop a modular and efficient "cycloaddition/ring-opening" strategy of bicyclo[1.1.0]butanes (BCBs) with triazinanes to provide a series of -diastereoselective cyclobutylamines via 2,4-diazabicyclo[4.
View Article and Find Full Text PDFA series of novel sulfonyl hydrazide based β-carboline derivatives (SX1-SX32) were designed and synthesized, and their structures were characterized on NMR and HRMS. Their α-glucosidase inhibitory screening results found that compounds (SX1-SX32) presented potential α-glucosidase inhibitory: IC values being 2.12 ± 0.
View Article and Find Full Text PDFThe soil microbial carbon pump (MCP) is increasingly acknowledged as being directly linked to soil organic carbon (SOC) accumulation and stability. Given the close coupling of carbon (C) and nitrogen (N) cycles and the constraints imposed by their stoichiometry on microbial growth, N addition might affect microbial growth strategies with potential consequences for necromass formation and carbon stability. However, this topic remains largely unexplored.
View Article and Find Full Text PDFHerein, a B(CF)-catalyzed formal ( + 3) ( = 5 and 6) cycloaddition of bicyclo[1.1.0]butanes (BCBs) with imidazolidines/hexahydropyrimidines is described.
View Article and Find Full Text PDFThis article investigates a laser-directed energy deposition additive manufacturing (AM) method, based on coaxial powder feeding, for preparing quartz glass. Through synergistic optimization of line deposition and plane deposition experiments, key parameters of laser coaxial powder feeding AM were identified. The corresponding mechanical properties, thermal properties, and microstructure of the bulk parts were analyzed.
View Article and Find Full Text PDFA rhodium-catalyzed carbene N-H insertion protocol for simultaneously controlling the C-N axial and spiro-central chiralities is disclosed, resulting in the rapid assembly of enantiopure -arylindolinone-spiroacetal derivatives in high yields with excellent enantioselectivities. This promising strategy features the chiral C-N axis, spiro-central chirality, functional group tolerance, and late-stage diversification. DFT calculations indicate that the N-H insertion is the axial-chirality-determining step and that the 1,5-H shift step is regiospecifically caused by the spirocycle.
View Article and Find Full Text PDFBackground: Herbivore-induced plant volatiles (HIPVs) are important self-defense outputs of pepper plants to resist insect pests. Ascoviruses are pathogenic to the larvae of most lepidopteran vegetable pests. However, whether Heliothis virescens ascovirus 3h (HvAV-3h)-infected Spodoptera litura larvae can change pepper leaf HIPVs is not well understood.
View Article and Find Full Text PDFAn N-heterocyclic carbene (NHC)-catalyzed [3 + 3] cycloaddition of α-bromoenals with nitroketene aminals or nitroketene ,-acetals has been developed. This methodology provides an efficient strategy for the construction of valuable nitro-containing heterocyclic compounds. This protocol features mild reaction conditions, easily available starting materials, broad substrate scope and easy scalability.
View Article and Find Full Text PDFIntroduction: A better understanding of the regulatory role of microorganisms on soil phosphorous (P) mobilization is critical for developing sustainable fertilization practices and reducing P resource scarcity. The genes regulate soil organic P (Po) mobilization.
Methods: Based on the long-term P application experiments in acid purple soil of maize system in Southwest China (started in 2010), the experiment included five P levels: 0, 16, 33, 49, and 65.
An unprecedented copper-catalyzed cascade reaction of 1,6-enynes with sulfoxonium ylides is reported, providing a series of structurally intriguing 2,3-disubstituted indolines bearing a conjugated dienone functionality at the 3-position in moderate to excellent yields with good chemo-, regio-, and diastereoselectivities under mild reaction conditions. Importantly, sulfoxonium-ylide-derived copper-carbene herein exhibits quite different reactivity from that of diazo copper-carbene. A rational mechanism, an initial ammonium ylide rather than allene formation, is proposed.
View Article and Find Full Text PDFA phenyliodine(III) diacetate-promoted/1,1,1,3,3,3-hexafluoroisopropanol-controlled dearomative spirocyclization of phenolic ketones was reported, providing two libraries of structurally interesting scaffolds, spirocyclohexadienonic ketals and their acetoxylated counterparts, in moderate to excellent yields under mild conditions. Control experiments unravel that the reaction proceeds through a spirocyclohexadienone-oxocarbenium cation species. In addition, an in situ-generated hypervalent iodine(III)-catalyzed version, as well as the late-stage transformation of products via conjugate additions, was also realized.
View Article and Find Full Text PDFThe reaction of vinylsulfonamides with donor-acceptor carbenes derived from α-aryldiazoesters, catalyzed by the -butyl glycine-derived dirhodium complex Rh(-4-Br-NTTL), has been reported. This method provides a variety of α-aryl-β-aminocyclopropane carboxylic acid derivatives bearing one quaternary carbon stereogenic center vicinal to the amino-substituted carbon in high yields with excellent diastereo- and enantioselectivities. Vinylsulfonamides showed complementary advantages over the well-developed vinylamides or vinylcarbamates for this Rh(II)-catalyzed cyclopropanation strategy.
View Article and Find Full Text PDFMicrobe-driven nitrification is a key process that affects nitrogen (N) utilization by plants and N loss to the environment in agro-ecosystems. Ammonia-oxidizing bacteria (AOB) and ammonia-oxidizing archaea (AOA) are important microorganisms that dominate the ammonia oxidation process (the first and rate-limiting step of nitrification). Calcareous soils are widely distributed, accounting for more than 30% of the Earth's land.
View Article and Find Full Text PDFAlthough utilization of fluorine compounds has a long history, synthesis of chiral fluorinated amino acid derivatives with structural diversity and high stereoselectivity is still very appealing and challenging. Here, we report a biomimetic study of enantioselective [1,3]-proton shift of β,β-difluoro-α-imine amides catalyzed by chiral quinine derivatives. A wide range of corresponding β,β-difluoro-α-amino amides were achieved in good yields with high enantioselectivities.
View Article and Find Full Text PDFThe complete mitochondrial genome (mitogenome) of was first reported. It is 15,314 bp in length (GenBank accession number: MW435592) and consists of 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, two ribosomal RNA (rRNA) genes. The nucleotide composition is A (41.
View Article and Find Full Text PDFBackground: The basis of individualized treatment should be individualized mortality risk predictive information. The present study aimed to develop an online individual mortality risk predictive tool for acute-on-chronic liver failure (ACLF) patients based on a random survival forest (RSF) algorithm.
Methods: The current study retrospectively enrolled ACLF patients from the Department of Infectious Diseases of The First People's Hospital of Foshan, Shunde Hospital of Southern Medical University, and Jiangmen Central Hospital.
An unprecedented copper-catalyzed tandem reaction of 1,6-enynes with diazo compounds via a cross-coupling/[2 + 2] cycloaddition sequence was reported. A library of methylenecyclobutane-fused ring systems including cyclobuta[]indolines, cyclobuta[]benzofuran, benzo[]cyclobuta[]thiophene, and bicyclo[3.2.
View Article and Find Full Text PDFMicrobes associated with phosphorus (P) cycling are intrinsic to soil P transformation and availability for plant use but are also influenced by the application of P fertilizer. Nevertheless, the variability in soil P in the field means that integrative analyses of soil P cycling, microbial composition, and microbial functional genes related to P cycling remain very challenging. In the present study in the North China Plain, we subjected the bacterial and fungal communities to amplicon sequencing analysis and characterized the alkaline phosphatase ( encoding bacterial alkaline phosphatase in a long-term field experiment (10 years) with six mineral P fertilization rates up to 200 kg P ha.
View Article and Find Full Text PDFZinc (Zn) fertilizer application can certainly improve the production and nutritional quality of cereal crops. However, Zn accumulation in the soil may lead to some deleterious environmental impacts in agroecosystems. The effects of long-term Zn application on soil microbial properties remain unclear, but it is imperative to understand such effects.
View Article and Find Full Text PDFAn unprecedented palladium(II)-catalyzed oxidative decarboxylative [2 + 2 + 1] annulation of cinnamic acids with alkynes has been developed for the synthesis of polysubstituted pentafulvenes. AgCO and DMSO are essential for the reaction. This protocol features readily available starting materials, a wide substrate scope, and moderate to excellent yields.
View Article and Find Full Text PDFA copper-catalyzed cascade reaction of diazo compounds with 1,-allenynes ( = 6,7) was reported, which provides efficient access to various functionalized 3-azabicyclo[.2.0] frameworks ( = 5,6) in moderate to excellent yields under mild reaction conditions.
View Article and Find Full Text PDFMuch effort has been directed toward increasing the availability of soil residual phosphorus (P). However, little information is available for the P fertilization-induced biotic P legacy and its mediation of plant P uptake. We collected microbial inocula from a monoculture maize field site with a 10-year P-fertilization history.
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