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1.
Heliyon ; 9(6): e17159, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37332945

RESUMO

Chinese Golden Courses was proposed by the Ministry of Education of China in 2018. It consists of five types. Virtual Simulation Golden Course is one of them. The college students are often faced with the problems of few opportunities, higher cost, higher risk and poorer effect during the internship in logistics courses. Virtual simulation experiment course is an important means to solve this kind of practical teaching problem. Green Logistics Virtual Simulation Experiment (GLVSE), a course built according to Virtual Simulation Golden Course, as a case was reported. The development process of GLVSE such as designing reasonable talent training architecture, reflecting Two Properties and One Degree, cooperating between schools and enterprises, and reforming the teaching mode with the way of "mixed online and offline" were introduced in detail. Six successful experiences and a model of building virtual simulation golden course are summed up. The report provides important references for developing high-quality virtual simulation courses not only for Chinese universities but also for other universities in the world.

2.
J Org Chem ; 87(7): 4955-4960, 2022 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-35317556

RESUMO

A highly efficient asymmetric synthesis of the IDO inhibitor navoximod, featuring the stereoselective installation of two relative and two absolute stereocenters from an advanced racemic intermediate, is described. The stereocenters were set via a crystallization-induced dynamic resolution along with two selective ketone reductions: one via a biocatalytic ketoreductase transformation and one via substrate-controlled hydride delivery from LiAlH(Ot-Bu)3. Following this strategy, navoximod was synthesized in 10 steps from 2-fluorobenzaldehyde and isolated in 23% overall yield with 99.7% ee and high purity.


Assuntos
Inibidores Enzimáticos , Indóis , Inibidores Enzimáticos/farmacologia , Imidazóis , Estereoisomerismo
3.
Materials (Basel) ; 14(15)2021 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-34361380

RESUMO

Methyl-modified, cobalt-doped silica (Co/MSiO2) materials were synthesized by sol-gel technique calcined in N2 atmospheres, and membranes were made thereof by coating method. The effects of Co/Si molar ratio (nCo) on the physical-chemical constructions of Co/MSiO2 materials and microstructures of Co/MSiO2 membranes were systematically investigated. The gas permeance performance and hydrothermal stability of Co/MSiO2 membranes were also tested. The results show that the cobalt element in Co/MSiO2 material calcined at 400 °C exists not only as Si-O-Co bond but also as Co3O4 and CoO crystals. The introduction of metallic cobalt and methyl can enlarge the total pore volume and average pore size of the SiO2 membrane. The activation energy (Ea) values of H2, CO2, and N2 for Co/MSiO2 membranes are less than those for MSiO2 membranes. When operating at a pressure difference of 0.2 MPa and 200 °C compared with MSiO2 membrane, the permeances of H2, CO2, and N2 for Co/MSiO2 membrane with nCo = 0.08 increased by 1.17, 0.70, and 0.83 times, respectively, and the perm-selectivities of H2/CO2 and H2/N2 increased by 27.66% and 18.53%, respectively. After being steamed and thermally regenerated, the change of H2 permeance and H2 perm-selectivities for Co/MSiO2 membrane is much smaller than those for MSiO2 membrane.

4.
Org Lett ; 21(22): 9099-9103, 2019 11 15.
Artigo em Inglês | MEDLINE | ID: mdl-31668077

RESUMO

We report herein an efficient, stereocontrolled, and chromatography-free synthesis of the novel broad spectrum antibiotic GDC-5338. The route features the construction of a functionalized tripeptide backbone, a high-yielding macrocyclization via a Pd-catalyzed Suzuki-Miyaura reaction, and the late-stage elaboration of key amide bonds with minimal stereochemical erosion. Through extensive reaction development and analytical understanding, these key advancements allowed the preparation of GDC-5338 in 17 steps, 15% overall yield, >99 A % HPLC, and >99:1 dr.


Assuntos
Antibacterianos/síntese química , Oligopeptídeos/química , Catálise , Ciclização , Bactérias Gram-Negativas , Paládio/química , Estereoisomerismo
5.
Org Lett ; 18(15): 3586-9, 2016 08 05.
Artigo em Inglês | MEDLINE | ID: mdl-27404018

RESUMO

A direct oxidative C-H amination affording 1-acetyl indolecarboxylates starting from 2-acetamido-3-arylacrylates has been achieved. Indole-2-carboxylates can be targeted with a straightforward deacetylation of the initial reaction products. The C-H amination reaction is carried out using a catalytic Pd(II) source with oxygen as the terminal oxidant. The scope and application of this chemistry is demonstrated with good to high yields for numerous electron-rich and electron-poor substrates. Further reaction of selected products via Suzuki arylation and deacetylation provides access to highly functionalized indole structures.


Assuntos
Indóis/síntese química , Compostos Organometálicos/química , Paládio/química , Aminação , Catálise , Indóis/química , Estrutura Molecular
6.
Angew Chem Int Ed Engl ; 55(28): 8054-7, 2016 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-27214849

RESUMO

A method for the trifluoromethylation of arylsilanes is reported. The reaction proceeds with [(phen)CuCF3 ] as the CF3  source under mild, oxidative conditions with high functional-group compatibility. This transformation complements prior trifluoromethylation of arenes in several ways. Most important, this method converts arylsilanes formed by the silylation of aryl C-H bonds to trifluoromethylarenes, thereby allowing the conversion of arenes to trifluoromethylarenes. The unique capabilities of the reported method are demonstrated by the conversion of a C-H bond into a C-CF3 bond in active pharmaceutical ingredients which do not undergo this overall transformation by alternative functionalization processes, including a combination of borylation and trifluoromethylation.


Assuntos
Cobre/química , Hidrocarbonetos Aromáticos/química , Hidrocarbonetos Fluorados/química , Silanos/química , Catálise , Halogenação , Hidrocarbonetos Aromáticos/síntese química , Hidrocarbonetos Fluorados/síntese química , Metilação , Oxirredução , Silanos/síntese química
7.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 10): o1864, 2008 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-21201081

RESUMO

The title compound, C(14)H(12)N(2)O(3), was synthesized by the condensation of salicylaldehyde with 3-hydroxy-benzo-hydrazide. The dihedral angle between the two benzene rings is 12.4 (2)°. The 2-hydr-oxy group forms an intra-molecular O-H⋯N hydrogen bond with the imide N atom. Mol-ecules are linked through inter-molecular O-H⋯O and N-H⋯O hydrogen bonds into a two-dimensional polymeric structure parallel to the ab plane.

8.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 10): o1995, 2008 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-21201194

RESUMO

The title compound, C(14)H(12)BrN(3)O(3), was prepared by reaction of 5-bromo-3-methoxy-salicylaldehyde and isonicotinohydrazide in methanol. The mol-ecule is not planar and adopts a trans configuration with respect to the C=N bond. There is an intra-molecular O-H⋯N hydrogen bond in the mol-ecule. The dihedral angle between the benzene and pyridine rings is 12.2 (2)°. In the crystal structure, mol-ecules are linked through inter-molecular N-H⋯N hydrogen bonds, forming chains running along the c-axis direction.

9.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 10): o1996-7, 2008 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-21201195

RESUMO

The title compound, C(14)H(13)N(3)O(3)·H(2)O, was prepared by the reaction of 4-methoxy-salicylaldehyde and isonicotinohydrazide in ethanol. The Schiff base mol-ecule is not planar and has an E configuration with respect to the methyl-idene unit. The dihedral angle between the benzene and pyridine rings is 36.8 (2)°. In the mol-ecule there is an intra-molecular O-H⋯N hydrogen bond involving the hydroxyl substituent and the N atom of the 2-hydr-oxy-4-methoxy-benzyl-idene unit. In the crystal, the mol-ecules are linked through inter-molecular O-H⋯O, O-H⋯N and N-H⋯O hydrogen bonds, forming layers parallel to the bc plane.

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