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1.
Fa Yi Xue Za Zhi ; 39(2): 144-150, 2023 Apr 25.
Artículo en Inglés, Zh | MEDLINE | ID: mdl-37277377

RESUMEN

OBJECTIVES: To identify 1-(4-fluorophenyl)-2-(1-pyrrolidinyl) pentan-1-one (4-F-α-PVP) analog 1-(4-fluoro-3-methyl phenyl)-2-(1-pyrrolidinyl) pentan-1-one (4-F-3-Methyl-α-PVP) hydrochloride without reference substance. METHODS: The direct-injection electron ionization-mass spectrometry (EI-MS), GC-MS, electrospray ionization-high resolution mass spectrometry (ESI-HRMS), ultra-high performance liquid chromatography-high resolution tandem mass spectrometry (UPLC-HRMS/MS), nuclear magnetic resonance (NMR), ion chromatography and Fourier transform infrared spectroscopy (FTIR) were integrated utilized to achieve the structural analysis and characterization of the unknown compound in the sample, and the cleavage mechanism of the fragment ions was deduced by EI-MS and UPLC-HRMS/MS. RESULTS: By analyzing the direct-injection EI-MS, GC-MS, ESI-HRMS and UPLC-HRMS/MS of the compound in the samples, it was concluded that the unknown compound was a structural analog of 4-F-α-PVP, possibly with one more methyl group in the benzene ring. According to the analysis results of 1H-NMR and 13C-NMR, it was further proved that the methyl group is located at the 3-position of the benzene ring. Since the actual number of hydrogen in 1H-NMR analysis was one more than 4-F-3-Methyl-α-PVP neutral molecule, it was inferred that the compound existed in the form of salt. Ion chromatography analysis results showed that the compound contained chlorine anion (content 11.14%-11.16%), with the structural analysis of main functional group information by FTIR, the unknown compound was finally determined to be 4-F-3-Methyl-α-PVP hydrochloride. CONCLUSIONS: A comprehensive method using EI-MS, GC-MS, ESI-HRMS, UPLC-HRMS/MS, NMR, ion chromatography and FTIR to identify 4-F-3-Methyl-α-PVP hydrochloride in samples is established, which will be helpful for the forensic science laboratory to identify this compound or other analog compounds.


Asunto(s)
Benceno , Espectrometría de Masa por Ionización de Electrospray , Cromatografía de Gases y Espectrometría de Masas/métodos , Cromatografía Líquida de Alta Presión/métodos
2.
Zhongguo Zhong Yao Za Zhi ; 45(13): 3112-3119, 2020 Jul.
Artículo en Zh | MEDLINE | ID: mdl-32726019

RESUMEN

The WRKY family genes, which play an important role in plant morphogenesis and stress response, were selected based on the data of the full-length transcriptome of Asarum heterotropoides. Using AtWRKY33, which regulates the synthesis of the camalexin in the model plant Arabidopsis to compare homologous genes in A. heterotropoides, primers were designed to amplify the open reading frame(ORF) fragment of AhWRKY33 gene by RT-PCR using total RNA of A. heterotropoides leaves as template. Real-time PCR results showed that there was a significant difference between the aerial part and the underground part of A. heterotropoides, the toxic aristolochic acid content is highly expressed in the leaves higher than the root. After verification, the WRKY33 gene of A. heterotropoides is ORF long 1 686 bp, encoding 561 amino acids.AhWRKY33 had two conserved WRKYGQK domains. According to the classical classification, it belongs to group Ⅰ WRKY transcription factor. A. heterotropoides WRKY33 had some homology with amino acids of other species. The study successfully constructed the plant eukaryotic expression vector PHG-AhWRKY33 and transformed Arabidopsis thaliana, the transgenic Arabidopsis was obtained by PCR detection and hygromycin resistant plate screening. It found that the germination of transgenic Arabidopsis seeds was accelerated and the stress resistance was increased. It laid a foundation for further analysis of WRKY transcription factor in the growth and development of A. heterotropoides and the synthesis of secondary metabolites.


Asunto(s)
Proteínas de Arabidopsis/genética , Arabidopsis/genética , Asarum , Clonación Molecular , Regulación de la Expresión Génica de las Plantas , Hojas de la Planta , Proteínas de Plantas/genética , Factores de Transcripción , Transformación Genética
3.
J Org Chem ; 82(19): 9988-9994, 2017 10 06.
Artículo en Inglés | MEDLINE | ID: mdl-28836441

RESUMEN

Under Pd catalysis with a newly synthesized electron-deficient heterocycle, 2-(4,5-dihydroimidazol-2-yl)pyrimidine (as the ligand), the reaction of α,ß-unsaturated esters with arylboronic acids afforded a wide range of 3,3-disubstituted indan-1-ones bearing a quaternary carbon in high yields. Mechanistic studies revealed that the reaction involves a tandem conjugate addition/1,4-Pd shift followed by a cyclization.

4.
Gene ; 828: 146462, 2022 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-35413394

RESUMEN

Terpenoids are widely distributed in plants and play important roles in the regulation of plant growth and development and in the interactions between plants and both the environment and other organisms. However, terpene synthase (TPS) genes have not been systematically investigated in the tetraploid Gossypium hirsutum. In this study, whole genome identification and characterization of the TPS family from G. hirsutum were carried out. Eighty-five TPS genes, including 47 previously unidentified genes, were identified in the G. hirsutum genome and classified into 5 subfamilies according to protein sequence similarities, as follows: 43 GhTPS-a, 29 GhTPS-b, 4 GhTPS-c, 7 GhTPS-e/f, and 2 GhTPS-g members. These 85 TPS genes were mapped onto 19 chromosomes of the G. hirsutum genome. Segmental duplications and tandem duplications contributed greatly to the expansion of TPS genes in G. hirsutum and were followed by intense purifying selection during evolution. Indentification of cis-acting regulatory elements suggest that the expression of TPS genes is regulated by a variety of hormones. RNA sequencing (RNA-seq) expression profile analysis revealed that the TPS genes had distinct spatiotemporal expression patterns, and several genes were highly and preferentially expressed in the leaves of cotton with gossypol glands (glanded cotton) versus a glandless strain. Virus-induced gene silencing (VIGS) of three TPS genes yielded plants characterized by fewer, smaller, and lighter gossypol glands, which indicated that these three genes were responsible for gland activity. Taken together, our results provide a solid basis for further elucidation of the biological functions of TPS genes in relation to gland activity and gossypol biosynthesis to develop cotton cultivars with low cottonseed gossypol contents.


Asunto(s)
Transferasas Alquil y Aril , Gosipol , Transferasas Alquil y Aril/genética , Transferasas Alquil y Aril/metabolismo , Regulación de la Expresión Génica de las Plantas , Gossypium , Gosipol/metabolismo , Familia de Multigenes , Filogenia , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo
5.
Chem Commun (Camb) ; 55(45): 6449-6452, 2019 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-31099378

RESUMEN

A highly efficient catalyst for Pd-catalyzed cyclopropanation was developed using a bulkier N-heterocyclic carbene ligand, with which the nitriles reacted with mono substituted allyl reagents to afford cyclopropanes in high yields with high cyclopropanation/allylation and enantioselectivities. The reasons for cyclopropanation were investigated and the usefulness of the products was demonstrated.

6.
Org Lett ; 21(17): 6805-6810, 2019 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-31407913

RESUMEN

The activated alkynes have been used successfully for the first time as the dipolarophile in the palladium-catalyzed asymmetric (3 + 2) cycloaddition, affording highly functionalized cyclopentenes in good to high yields with high chemoselectivities and good to high enantioselectivities. The introduction of an additional carbonyl group at the α-position of the alkynyl esters is the key to activating the carbon-carbon triple bond. The reaction process was investigated, and an inverse process of Pd-catalyzed (3 + 2) cycloaddition was observed.

7.
Org Lett ; 20(16): 4773-4776, 2018 08 17.
Artículo en Inglés | MEDLINE | ID: mdl-30080051

RESUMEN

Allenic amides are successfully developed as dipolarophiles to react with vinyl epoxides under Pd-catalysis. The chiral NHC showed its unique role as the ligand in this asymmetric [3 + 2] cycloaddition. Chiral tetrahydrofurans bearing three functional groups (monosubstituted alkene, tetrasubstituted enolether, and amide) and vicinal tertiary and quaternary stereocenters were obtained in high yields with high diastereo- and enantioselectivities.

8.
Chem Commun (Camb) ; 54(93): 13143-13146, 2018 Nov 20.
Artículo en Inglés | MEDLINE | ID: mdl-30403245

RESUMEN

1,1,2-Trisubstituted alkenes with a single strongly electronic withdrawing activator, which are unreactive electron-deficient alkenes in transition metal-catalyzed [3+2] cycloaddition with vinyl three-membered heterocycles, were used in the Pd-catalyzed asymmetric cycloaddition of vinyl epoxides, affording multifunctionalized tetrahydrofurans in high yields with high diastereo- and enantioselectivities.

9.
Chem Asian J ; 12(2): 212-215, 2017 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-27933754

RESUMEN

A new type of nucleophile, a 3-imino nitrile carbanion generated in situ by Thorpe reaction of acetonitrile with a base, was developed successfully and applied in a Pd-catalyzed asymmetric allylic alkylation with mono-substituted allyl reagents under Pd/SIOCPhox catalysis, affording ß-enaminonitrile products in high yields with excellent regio- and enantioselectivities.

10.
J Environ Sci (China) ; 17(1): 152-5, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-15900779

RESUMEN

In this study, 7 stains of Rhodopseudomonas sp. were selected from 36 photosynthetic bacteria stains storied in our laboratory. Rhodopseudomonas sp. strain 99-28 has the highest 5-aminolevulinic acid(ALA) production ability in these 7 strains. Rhodopseudomonas sp. 99-28 strain was mutated using ultraviolet radiation and a mutant strain L-1, which ALA production is higher than wild strain 99-28 about one times, was obtained. The elements affecting ALA formation of strain 99-28 and L-1 were studied. Under the optimal condition( pH 7.5, supplement of ALA dehydratase(ALAD) inhibitor, levulinic acid(LA) and precursors of ALA synthesis, glycine and succinat, 3000 Ix of light density), ALA formation of mutant L-1 was up to 22.15 mg/L. Strain L-1 was used to treat wastewater to remove COD(Cr) and produce ALA. ALA production was 2.819 mg/L, 1.531 mg/L, 2.166 mg/L, and 2.424 mg/L in monosodium glutamate wastewater(MGW), succotash wastewater(SW), brewage wastewater(BW), and citric acid wastewater(CAW) respectively. More than 90% of COD(Cr) was removed in four kinds of wastewater. When LA, glycin and succinate were supplied, ALA production was dramatically increased, however, COD(Cr) could hardly be removed.


Asunto(s)
Ácido Aminolevulínico/metabolismo , Reactores Biológicos , Rhodopseudomonas/metabolismo , Eliminación de Residuos Líquidos/métodos , Purificación del Agua/métodos , Ácido Glutámico , Glicina/metabolismo , Concentración de Iones de Hidrógeno , Ácidos Levulínicos/metabolismo , Luz , Malatos , Mutagénesis , Rhodopseudomonas/genética , Especificidad de la Especie , Ácido Succínico/metabolismo
11.
Zhonghua Liu Xing Bing Xue Za Zhi ; 25(3): 248-50, 2004 Mar.
Artículo en Zh | MEDLINE | ID: mdl-15200941

RESUMEN

OBJECTIVE: To study the resistance of methicillin-resistant staphylococcus aureus (MRSA), an indicator used in hospitals. METHODS: We used minimal inhibitory concentrations (MIC) of iodoph and chlorhexidine to MRSA, methicillin-sensitive staphylococcus aureus (MSSA) and staphylococcus aureus ATCC6538. RESULTS: Obvious difference between MRSA and MSSA the MIC of Iodophor was noticed. Among MICs, 5.3% MRSA strains were 2-folds and 28.9% MRSA strains were 1.5 fold more than staph. aureus ATCC6538, while the MIC of 11.1% MSSA strains raised 1.5 fold than ATCC6538. The MIC of 83.3% MSSA strains were the same to staph. aureus ATCC6538. The MIC of chlorhexidine to MRSA, MSSA and staphylococcus aureus ATTC6538 were similar to each other. CONCLUSION: Results showed that some MRSA were more resistant to Iodophor than staph. aureus ATCC6538, but remained the same resistance to Chlorhexidine. Thus the concentration of Iodophor should be raised when the resistant strains were isolated.


Asunto(s)
Antiinfecciosos/farmacología , Farmacorresistencia Bacteriana Múltiple , Staphylococcus aureus/efectos de los fármacos , Clorhexidina/farmacología , Humanos , Yodóforos/farmacología , Meticilina/farmacología , Resistencia a la Meticilina , Pruebas de Sensibilidad Microbiana
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