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1.
Org Biomol Chem ; 22(4): 784-789, 2024 Jan 24.
Artículo en Inglés | MEDLINE | ID: mdl-38168690

RESUMEN

This paper reports a novel method for the visible-light-mediated synthesis of quinazolinones from the reaction of benzyl bromides with 2-aminobenzamides. The reaction proceeded efficiently at room temperature upon irradiation with an 18 W blue light-emitting diode in air without photocatalysts or additives. By varying the solvent type, substrate molar ratio, and reaction time, the optimal reaction conditions, including the use of methanol solvent, room temperature, and reaction time of 28 h, were identified. Under these conditions, various quinazolinones were obtained using 18 substrates, with the highest yield of 93%. To determine the industrial value of the proposed method, a scale-up reaction was performed and 80% product yield was achieved. Mechanistic studies revealed that the reaction likely proceeded via a radical pathway and that the hydrogen bromide by-product generated during the first step of the reaction of benzyl bromide with 2-aminobenzamide promoted the subsequent step.

2.
Ecotoxicol Environ Saf ; 276: 116301, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38599159

RESUMEN

To study the heavy metal accumulation and its impact on insect exterior and chromosome morphology, and reveal the molecular mechanism of insects adapting to long-term heavy metal compound pollution habitats, this study, in the Diaojiang river basin, which has been polluted by heavy metals(HMs) for nearly a thousand years, two Eucriotettix oculatus populations was collected from mining and non-mining areas. It was found that the contents of 7 heavy metals (As, Cd, Pb, Zn, Cu, Sn, Sb) in E. oculatus of the mining area were higher than that in the non-mining 1-11 times. The analysis of morphology shows that the external morphology, the hind wing type and the chromosomal morphology of E. oculatus are significant differences between the two populations. Based on the heavy metal accumulation,morphological change, and stable population density, it is inferred that the mining area population has been affected by heavy metals and has adapted to the environment of heavy metals pollution. Then, by analyzing the transcriptome of the two populations, it was found that the digestion, immunity, excretion, endocrine, nerve, circulation, reproductive and other systems and lysosomes, endoplasmic reticulum and other cell structure-related gene expression were suppressed. This shows that the functions of the above-mentioned related systems of E. oculatus are inhibited by heavy metal stress. However, it has also been found that through the significant up-regulation of genes related to the above system, such as ATP2B, pepsin A, ubiquitin, AQP1, ACOX, ATPeV0A, SEC61A, CANX, ALDH7A1, DLD, aceE, Hsp40, and catalase, etc., and the down-regulation of MAPK signalling pathway genes, can enhanced nutrient absorption, improve energy metabolism, repair damaged cells and degrade abnormal proteins, maintain the stability of cells and systems, and resist heavy metal damage so that E. oculatus can adapt to the environment of heavy metal pollution for a long time.


Asunto(s)
Saltamontes , Metales Pesados , Contaminantes Químicos del Agua , Animales , Metales Pesados/toxicidad , Contaminantes Químicos del Agua/toxicidad , Saltamontes/efectos de los fármacos , Saltamontes/anatomía & histología , Monitoreo del Ambiente/métodos , Minería , China , Adaptación Fisiológica/efectos de los fármacos , Transcriptoma/efectos de los fármacos , Ríos/química
3.
Chemistry ; 29(48): e202301121, 2023 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-37300353

RESUMEN

Lithium-sulfur (Li-S) batteries are a promising energy storage technology due to their tempting high theoretical capacity and energy density. Nevertheless, the wastage of active materials that originates from the shuttling effect of polysulfides still hinders advancement of Li-S batteries. The effective design of cathode materials is extremely pivotal to solve this thorny problem. Herein, surface engineering in covalent organic polymers (COPs) has been performed to investigate the influence of pore wall polarity on the performance of COP-based cathodes used for Li-S batteries. With the assistance of experimental investigation and theoretical calculations, performance improvement by increasing pore surface polarity and a synergy effect of the polarized functionalities, along with nano-confinement effect of the COPs, are disclosed, to which the improved performance of Li-S batteries including outstanding Coulombic efficiency (99.0 %) and extremely low capacity decay (0.08 % over 425 cycles at 1.0 C) is attributed. This work not only enlightens the designable synthesis and applications of covalent polymers as polar sulfur hosts with high utilization of active materials, but also provides a feasible guide for the design of effective cathode materials for future advanced Li-S batteries.

4.
J Org Chem ; 88(16): 11661-11674, 2023 Aug 18.
Artículo en Inglés | MEDLINE | ID: mdl-37552549

RESUMEN

We have developed a transition-metal-free radical approach for 1,2-alkynyl functionalization of unactivated alkenes through the combination of 3-exo-dig cyclization with alkynyl migration triggered by in situ-generated diverse radical precursors. This strategy provides a robust toolkit to access a variety of synthetically important α-functionalized alkynyl ketones, simultaneously installing densely functionalized carbonyl, alkynyl, and other various functional groups into the alkenes. The broad substrate scope, which includes distinctly electron-donating or electron-withdrawing alkynyl migrating groups, excellent functional group compatibility, and remarkable selectivity make this protocol practical and attractive.

5.
Org Biomol Chem ; 21(17): 3691-3696, 2023 May 03.
Artículo en Inglés | MEDLINE | ID: mdl-37070775

RESUMEN

We report a Brønsted acid-catalyzed C6 functionalization of 2,3-disubstituted indoles with 2,2-diarylacetonitriles for efficient construction of cyano-substituted all-carbon quaternary centers with excellent yields. The synthetic utility was demonstrated by the conversion of the cyano-group which enables the divergent preparation of aldehydes, primary amines and amides. Control experiments suggested that this process involves C-H oxidation of 2,2-diarylacetonitriles to in situ generate δ,δ-disubstituted p-quinone methide intermediates. This protocol provides an efficient method for C6 functionalization of 2,3-disubstituted indoles to construct all-carbon quaternary centers.

6.
Org Biomol Chem ; 18(44): 9095-9099, 2020 11 28.
Artículo en Inglés | MEDLINE | ID: mdl-33146660

RESUMEN

The amide group has one of the most significant functionalities found in many natural products. Herein, low-nucleophilic amides are used in a Mannich-type reaction to synthesize N-acyl-protected amine derivatives. A highly efficient synthetic method utilizing simple aldehydes, N-substituted anilines, and amides as substrates was established through a one-pot amide pathway activated by hydrogen bonding between the ZnCl2 and amide under solvent-free conditions. This strategy can be broadly applied to medicinal chemistry. More importantly, compared with the previous Lewis acid catalyzed reaction, we proposed a new application of zinc chloride.

7.
J Am Chem Soc ; 139(19): 6736-6743, 2017 05 17.
Artículo en Inglés | MEDLINE | ID: mdl-28445639

RESUMEN

Covalent organic frameworks (COFs) are an emerging class of crystalline porous organic materials which are fabricated via reticular chemistry. Their topologic structures can be precisely predicted on the basis of the structures of building blocks. However, constructing COFs with complicated structures has remained a great challenge, due to the limited strategies that can access to the structural complexity of COFs. In this work, we have developed a new approach to produce COFs bearing three different kinds of pores. The design is fulfilled by the combination of vertex-truncation with multiple-linking-site strategy. On the basis of this design, a "V"-shaped building block carrying two aldehyde groups on the end of each branch has been synthesized. Condensation of it with 1,4-diaminobenzene or benzidine leads to the formation of two triple-pore COFs, TP-COF-DAB and TP-COF-BZ, respectively. The topological structures of the triple-pore COFs have been confirmed by PXRD studies, synchrotron small-angle X-ray scattering (SAXS) experiments, theoretical simulations, and pore size distribution analyses. Furthermore, for the first time, an in situ COF-to-COF transformation has also been achieved by heating TP-COF-BZ with 1,4-diaminobenzene under solvothermal condition, which leads to the formation of TP-COF-DAB via in situ replacing the benzidine linkers in TP-COF-BZ with 1,4-diaminobenzene linkers.

8.
J Org Chem ; 82(10): 5441-5448, 2017 05 19.
Artículo en Inglés | MEDLINE | ID: mdl-28471176

RESUMEN

The di-tert-butyl peroxide (DTBP) induced coupling of arenesulfonylindoles with ethers such as 1,4-dioxane, tetrahydropyran, tetrahydrofuran, and 1,2-dimethoxyethane was studied. The distinguishing feature of this strategy was characterized by capturing in situ generated vinylogous imine intermediates for the C(sp3)-H bond alkylation of ethers. This general procedure presents the major advantages of its wide substrate scope and good functional group compatibility.

9.
Org Biomol Chem ; 15(6): 1325-1328, 2017 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-28102406

RESUMEN

An efficient access to optically active sulfahydantoins, 4-aryl-1,2,5-thiadiazolidin-3-one 1,1-dioxides, was developed through palladium-catalyzed asymmetric hydrogenation of the corresponding cyclic N-sulfonylketimines with up to 98% ee.

10.
Biol Res ; 50(1): 34, 2017 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-28982393

RESUMEN

OBJECTIVE: This study aimed to reveal the mitochondrial genomes (mtgenomes) of Tetrix japonica and Alulatettix yunnanensis, and the phylogenetics of Orthoptera species. METHODS: The mtgenomes of A. yunnanensis and T. japonica were firstly sequenced and assembled through partial sequences amplification, and then the genome organization and gene arrangement were analyzed. Based on nucleotide/amino acid sequences of 13 protein-coding genes and whole mtgenomes, phylogenetic trees were established on 37 Orthoptera species and 5 outgroups, respectively. RESULTS: Except for a regulation region (A+T rich region), a total of 37 genes were found in mtgenomes of T. japonica and A. yunnanensis, including 13 protein-coding genes, 2 ribosomal RNA genes, and 22 transfer RNA genes, which exhibited similar characters with other Orthoptera species. Phylogenetic tree based on 13 concatenated protein-coding nucleotide sequences were considered to be more suitable for phylogenetic reconstruction of Orthoptera species than amino acid sequences and mtgenomes. The phylogenetic relationships of Caelifera species were Acridoidea and Pamphagoidea > Pyrgomorphoidea > Pneumoroidea > Eumastacoidea > Tetrigoidea > Tridactyloidea. Besides, a sister-group relationship between Tettigonioidea and Rhaphidophoroidea was revealed in Ensifera. CONCLUSION: Concatenated protein-coding nucleotide sequences of 13 genes were suitable for reconstruction of phylogenetic relationship in orthopteroid species. Tridactyloidea was a sister group of Tetrigoidea in Caelifera, and Rhaphidophoroidea was a sister group of Tettigonioidea in Ensifera.


Asunto(s)
Evolución Molecular , Genoma Mitocondrial/genética , Saltamontes/genética , Animales , Secuencia de Bases , Saltamontes/clasificación , Filogenia , Análisis de Secuencia de ADN
11.
Chemistry ; 22(49): 17784-17789, 2016 Dec 05.
Artículo en Inglés | MEDLINE | ID: mdl-27778380

RESUMEN

Integrating different kinds of pores into one covalent organic framework (COF) endows it with hierarchical porosity and thus generates a member of a new class of COFs, namely, heteropore COFs. Whereas the construction of COFs with homoporosity has already been well developed, the fabrication of heteropore COFs still faces great challenges. Although two strategies have recently been developed to successfully construct heteropore COFs from noncyclic building blocks, they suffer from the generation of COF isomers, which decreases the predictability and controllability of construction of this type of reticular materials. In this work, this drawback was overcome by a multiple-linking-site strategy that offers precision construction of heteropore COFs containing two kinds of hexagonal pores with different shapes and sizes. This strategy was developed by designing a building block in which double linking sites are introduced at each branch of a C3 -symmetric skeleton, the most widely used scaffold to construct COFs with homogeneous porosity. This design provides a general way to precisely construct heteropore COFs without formation of isomers. Furthermore, the as-prepared heteropore COFs have hollow-spherical morphology, which has rarely been observed for COFs, and an uncommon staggered AB stacking was observed for the layers of the 2D heteropore COFs.

12.
Org Biomol Chem ; 14(29): 6937-41, 2016 Aug 07.
Artículo en Inglés | MEDLINE | ID: mdl-27345438

RESUMEN

A chiral phosphoric acid-catalyzed asymmetric transfer hydrogenation of 3-trifluoromethylthioquinolines has been successfully developed, providing direct and facile access to chiral 2,3-disubstituted 1,2,3,4-tetrahydroquinoline derivatives containing a stereogenic trifluoromethylthio group with up to 99% enantioselectivity.

13.
J Insect Sci ; 162016.
Artículo en Inglés | MEDLINE | ID: mdl-26810560

RESUMEN

The sweet potato leaf folder, Brachmia macroscopa, is an important pest in China. The complete mitogenome, which consists of 13 protein-coding genes (PCGs), 22 transfer RNA genes, two ribosomal RNA genes, and an A + T-rich region, was sequenced and found to be 15,394 bp in length (GeneBank no. KT354968). The gene order and orientation of the B. macroscopa mitogenome were similar to those of other sequenced lepidopteran species. All of the PCGs started with ATN as the canonical start codon except for cox1, which started with CGA. In regard to stop codons, most PCGs stopped at TAA except for cox2, which stopped at TA, and nad4, which stopped at a single T. Thirteen PCGs of the available species (33 taxa) were used to demonstrate phylogenetic relationships. The ditrysian cluster was supported as a monophyletic clade at high levels by using maximum likelihood and Bayesian methods. The apoditrysian group, covering the Gelechioidea, formed a monophyletic clade with a bootstrap value of 88% and a posterior probability of 1.00. The superfamily Gelechioidea was supported as a monophyletic lineage by a posterior probability of 1.00.


Asunto(s)
Genoma de los Insectos/genética , Mitocondrias/genética , Mariposas Nocturnas/genética , Animales , Filogenia , Reacción en Cadena de la Polimerasa , ARN Ribosómico/genética
14.
Molecules ; 19(12): 19665-77, 2014 Nov 27.
Artículo en Inglés | MEDLINE | ID: mdl-25438078

RESUMEN

A mild and efficient method catalyzed by α-chymotrypsin was developed for the synthesis of bis(indolyl)methanes through a cascade process between indole and aromatic aldehydes. In the ethanol aqueous solution, a green medium, a wide range of aromatic aldehydes could react with indole to afford the desired products with moderate to good yields (from 68% to 95%) using a little α-chymotrypsin as catalyst.


Asunto(s)
Biocatálisis , Química Orgánica/métodos , Quimotripsina/metabolismo , Indoles/síntesis química , Metano/síntesis química , Animales , Bovinos , Etanol/química , Indoles/química , Metano/química , Sus scrofa , Temperatura
15.
Chem Commun (Camb) ; 60(62): 8107-8110, 2024 Jul 30.
Artículo en Inglés | MEDLINE | ID: mdl-38993176

RESUMEN

A visible-light-induced directed decarboxylative disulfuration of α-keto acids and oxamic acids was developed. As a result, a series of versatile mono acyl disulfide derivatives was synthesized under mild and sustainable reaction conditions. This protocol has a broad substrate scope, good functional-group tolerance, and excellent synthetic applications.

16.
Mol Genet Genomics ; 288(11): 627-38, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23996145

RESUMEN

Studies on the cockroach have contributed to our understanding of several important developmental processes, especially those that can be easily studied in the embryo. However, our knowledge on late events such as gonad differentiation in the cockroach is still limited. The major aim of the present study was to identify sex-specific genes between adult female and male Periplaneta americana. Two cDNA libraries were constructed using the suppression subtractive hybridization method; a total of 433 and 599 unique sequences were obtained from the forward library and the reverse library, respectively, by cluster assembly, and sequence alignment of 1,032 expressed sequence tags. The analysis of the differentially expressed gene functions allowed these genes to be categorized into three groups: biological process, molecular function, and cellular component. The differentially expressed genes were suggested to be related to the development of the gonads of P. americana. Twelve differentially expressed genes were randomly selected and verified using relative quantitative real-time polymerase chain reaction (qRT-PCR). Meanwhile, by adopting a range of filtering criteria, we predicted two potential microRNA sequences for P. americana, pam-miR100-3p and pam-miR7. To confirm the expression of potential microRNAs (miRNAs) in American cockroach, a qRT-PCR approach was also employed. The data presented here offer the insights into the molecular foundation of sex differences in American cockroach, and the first report for the miRNAs in this species. In addition, the results can be used as a reference for unraveling candidate genes associated with the sex and reproduction of cockroaches.


Asunto(s)
Regulación de la Expresión Génica , MicroARNs/genética , Hibridación de Ácido Nucleico/métodos , Periplaneta/genética , Animales , Secuencia de Bases , ADN Complementario/genética , Etiquetas de Secuencia Expresada , Femenino , Perfilación de la Expresión Génica , Biblioteca de Genes , Masculino , Datos de Secuencia Molecular , Especificidad de Órganos , Ovario/fisiología , Periplaneta/fisiología , Filogenia , Alineación de Secuencia , Análisis de Secuencia de ADN , Factores Sexuales , Testículo/fisiología
17.
Molecules ; 18(11): 13910-9, 2013 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-24284489

RESUMEN

An environmentally-friendly, enzyme-promoted procedure for the Henry reaction was first studied using water-in-[Bmim][PF6] microemulsions as reaction medium. The Amano acylase from Aspergillus oryzae showed better catalytic activity for the addition reactions of nitromethane with a series of aromatic aldehydes, and a highest yield of 90% was obtained.


Asunto(s)
Amidohidrolasas/metabolismo , Aspergillus oryzae/enzimología , Aldehídos/química , Aldehídos/metabolismo
18.
Curr Genet ; 58(2): 65-77, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22311390

RESUMEN

The mitochondrial genomes are one of the most information-rich markers in phylogenetics. The relationships within superorder Dictyoptera have been debated in the literature. However, the closely related termites (Isoptera) are retained as unranked taxon within the order Blattaria (cockroaches). In this work, we sequenced the complete mitogenomes of two cockroaches, reconstructed the molecular phylogeny and attempted to infer the phylogenetic position of termites in Blattaria more reliably. The complete mtDNA nucleotide sequences of the peridomestic American cockroach (Periplaneta americana L.) and the domestic German cockroach (Blattella germanica L.) are 15,025 and 15,584 bp in size, respectively. The genome shares the gene order and orientation with previously known Blattaria mitogenomes. Most tRNAs could be folded into the typical cloverleaf secondary structure, but the tRNA-Ser (AGN) of P. americana appears to be missing the dihydrouridine arm. Using nucleotide and amino acid sequences as phylogenetic markers, we proposed that termites should be treated as a superfamily (Termitoidea) of cockroaches. We suggested that Polyphagoidea was the sister group of Termitoidea in Blattaria and supported that the suborder Caelifera is more closely related to the Phasmatodea than to the suborder Ensifera of Orthoptera.


Asunto(s)
Cucarachas/genética , Genoma Mitocondrial , Isópteros/genética , Periplaneta/genética , Filogenia , Animales , Secuencia de Bases , Orden Génico , Datos de Secuencia Molecular
19.
RSC Adv ; 12(28): 17984-17989, 2022 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-35765318

RESUMEN

In this study, a covalent organic framework (TpPa-SO3H) photocatalyst with sulfonic acid function groups was synthesized using a solvothermal method. The morphologies and structural properties of the as-prepared composites were characterized by X-ray diffraction, infrared spectroscopy, ultraviolet-visible diffuse reflectance spectroscopy, X-ray photoelectron spectroscopy, N2 adsorption-desorption measurements, and field emission scanning electron microscopy. An electrochemical workstation was used to test the photoelectric performance of the materials. The results show that TpPa-SO3H has -SO3H functional groups and high photocatalytic performance for CO2 reduction. After 4 h of visible-light irradiation, the amount of CO produced is 416.61 µmol g-1. In addition, the TpPa-SO3H photocatalyst exhibited chemical stability and reusability. After two testing cycles under visible light irradiation, the amount of CO produced decreased slightly to 415.23 and 409.15 µmol g-1. The XRD spectra of TpPa-SO3H were consistent before and after the cycles. Therefore, TpPa-SO3H exhibited good photocatalytic activity. This is because the introduction of -SO3H narrows the bandgap of TpPa-SO3H, which enhances the visible light response range and greatly promotes the separation of photogenerated electrons.

20.
Metabolites ; 12(9)2022 Aug 27.
Artículo en Inglés | MEDLINE | ID: mdl-36144209

RESUMEN

Holometabolism is a form of insect development which includes four life stages: egg, larva, pupa, and imago (or adult). The developmental change of whole body in metabolite levels of holometabolous insects are usually ignored and lack study. Diapause is an alternative life-history strategy that can occur during the egg, larval, pupal, and adult stages in holometabolous insects. Kallima inachus (Lepidoptera: Nymphalidae) is a holometabolous and adult diapausing butterfly. This study was intended to analyze metabolic changes in K. inachus during ontogeny and diapause through a non-targeted UPLC-MS/MS (ultra-performance liquid chromatograph coupled with tandem mass spectrometry) based metabolomics analysis. A variety of glycerophospholipids (11), amino acid and its derivatives (16), and fatty acyls (nine) are crucial to the stage development of K. inachus. 2-Keto-6-acetamidocaproate, N-phenylacetylglycine, Cinnabarinic acid, 2-(Formylamino) benzoic acid, L-histidine, L-glutamate, and L-glutamine play a potentially important role in transition of successive stages (larva to pupa and pupa to adult). We observed adjustments associated with active metabolism, including an accumulation of glycerophospholipids and carbohydrates and a degradation of lipids, as well as amino acid and its derivatives shifts, suggesting significantly changed in energy utilization and management when entering into adult diapause. Alpha-linolenic acid metabolism and ferroptosis were first found to be associated with diapause in adults through pathway analyses. Our study lays the foundation for a systematic study of the developmental mechanism of holometabolous insects and metabolic basis of adult diapause in butterflies.

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