Publications by authors named "Ping-an Wang"

A series of chiral bifunctional organocatalysts were prepared and used for enantioselective synthesis of 3-substituted isoindolinones from 2-formylarylnitriles and malonates through aldol-cyclization rearrangement tandem reaction in excellent yields and enantioselectivites (up to 87% yield and 95% ) without recrystallization. In this investigation, we found that chiral tertiary-amine catalysts with a urea group can afford 3-substituted isoindolinones both in higher yields (87% 77%) and enantioselectivities (95% 46% ) than chiral bifunctional phase-transfer catalysts.

View Article and Find Full Text PDF

A highly efficient asymmetric Michael addition of bulky glycine imine to α,β-unsaturated isoxazoles has been achieved by using 5 mol% of chiral cyclopropenimine as a chiral organo-superbase catalyst under mild conditions. Michael adducts were obtained in excellent yields (up to 97%) and stereoselectivities (up to >99 : 1 dr and 98% ee). A significant solvent effect was found in these chiral organosuperbase catalyzed asymmetric Michael reactions.

View Article and Find Full Text PDF

A series of bifunctional phase-transfer catalysts (PTCs) were synthesized to catalyze the [3 + 2] coupling reaction of isocyanates and epoxides to afford 2-oxazolidinones in good to high yields (up to 92% yield) using PhCl as a solvent at 100 °C within 12 h. These bifunctional PTCs were easily prepared from commercially available tertiary-primary diamines and isocyanates (or isothiocyanates, mono-squaramides, respectively) in two simple steps with good modularity and demonstrated high efficiency (2.5 mol% catalyst-loading).

View Article and Find Full Text PDF
Article Synopsis
  • The study focuses on efficiently creating β-functional nitroalkanes via direct Michael reactions on trans-β-nitroolefins using a grinding method without solvents.
  • Grinding reactions were performed at room temperature using available materials, resulting in various activated compounds reacting successfully.
  • The new method is fast, clean, and produces high yields of β-functional nitroalkanes in 5 to 10 minutes, indicating its potential for use as building blocks in organic synthesis.
View Article and Find Full Text PDF

The genetic manipulation of basidiomycete mushrooms is notoriously difficult and immature, and there is a lack of research reports on clustered regularly interspaced short palindromic repeat (CRISPR) based gene editing of functional genes in mushrooms. In this work, Ganoderma lucidum, a famous traditional medicinal basidiomycete mushroom, which produces a type of unique triterpenoid-anti-tumor ganoderic acids (GAs), was used, and a CRISPR/CRISPR-associated protein-9 nuclease (Cas9) editing system for functional genes of GA biosynthesis was constructed in the mushroom. As proof of concept, the effect of different gRNA constructs with endogenous u6 promoter and self-cleaving ribozyme HDV on ura3 disruption efficiency was investigated at first.

View Article and Find Full Text PDF

BES1 and BZR1 were originally identified as two key transcription factors specifically regulating brassinosteroid (BR)-mediated gene expression. They belong to a family consisting of six members, BES1, BZR1, BEH1, BEH2, BEH3, and BEH4. bes1 and bzr1 single mutants do not exhibit any characteristic BR phenotypes, suggesting functional redundancy of these proteins.

View Article and Find Full Text PDF

A one-pot, base-catalyzed, tandem grinding process involving carrying out aldol condensation and Michael addition in sequence to produce 3,4,5-trisubstituted isoxazoles from 3,5-dimethyl-4-nitroisoxazole, aromatic aldehydes and activated methylene compounds has been developed. In the presence of 10 mol% of pyrrolidine, aldol condensations of 3,5-dimethyl-4-nitroisoxazole with various aromatic aldehydes were performed with 3-10 minutes of grinding to provide 5-styryl-3-methyl-4-nitroisoxazoles in good to quantitative yields without further purification. Then, Michael additions between 5-styryl-3-methyl-4-nitroisoxazoles and activated methylene compounds (including ethyl 2-nitroacetate and alkyl 2-cyanoacetates) were carried out in the presence of 10 mol% of EtN in the same mortar with 3-5 minutes of continuous grinding to produce 3,4,5-trisubstituted isoxazoles in good to excellent yields.

View Article and Find Full Text PDF

A novel series of glucosyl thioureas were synthesized in good overall yields (up to 37% over four steps) from d-glucose and primary amines, and their larvicidal activities toward Mythimna separata Walker were also investigated. This new class of glucosyl thioureas demonstrated low to moderate growth inhibition activity of Mythiman separata Walker, with a growth inhibitory rate of up to 47.5% at a concentration of 100.

View Article and Find Full Text PDF

Well-defined unnatural dipeptide-alcohols based on a cis-2,5-disubstitued pyrrolidine backbone were synthesized from commercially available starting materials meso-diethyl-2,5-dibromoadipate, (S)-(-)-1-phenylethylamine, and phenylalaninol. The structures of these unnatural dipeptide-alcohols are supported by HRMS, 1H- and 13C-NMR spectroscopy. These unnatural dipeptide-alcohols can act as building blocks for peptidomimetics.

View Article and Find Full Text PDF

Enantioselective desymmetrization of meso-aziridines and meso-epoxides with various nucleophiles by organocatalysis has emerged as a cutting-edge approach in recent years. This review summarizes the origin and recent developments of enantioselective desymmetrization of meso-aziridines and meso-epoxides in the presence of organocatalysts.

View Article and Find Full Text PDF

Although hyperhomocysteinemia (hHcys) has been recognized as an important independent risk factor in the progression of end-stage renal disease and in the development of cardiovascular complications related to end-stage renal disease, the mechanisms triggering the pathogenic actions of hHcys are not yet fully understood. The present study was designed to investigate the contribution of nucleotide-binding oligomerization domain containing 2 (NOD2), an intracellular innate immunity mediator, to the development of glomerulosclerosis in hHcys. Our results showed that NOD2 deficiency ameliorated renal injury in mice with hHcys.

View Article and Find Full Text PDF

A series of chiral 10-heteroazatriquinanes were synthesized from enantiopure asymmetric cis-2,5-disubstituted pyrrolidines through a one-pot tandem cyclization procedure. The structures and configurations of these new chiral 10-heteroazatriquinanes are confirmed by X-ray single-crystal diffraction analysis.

View Article and Find Full Text PDF

Histone deacetylases (HDACs)-mediated epigenetic mechanisms play critical roles in the homeostasis of histone acetylation and gene transcription. HDAC inhibitors have displayed neuroprotective properties in animal models for various neurological diseases including Alzheimer's disease and ischaemic stroke. However, some studies have also reported that HDAC enzymes exert protective effects in several pathological conditions including ischaemic stress.

View Article and Find Full Text PDF

The synthesis and detailed characterization of gold nanoparticles (AuNPs) inside human hair has been achieved by treatment of hair with HAuCl(4) in alkaline medium. The AuNPs, which show a strong red fluorescence under blue light, are generated inside the fiber and are arranged in the cortex in a remarkably regular pattern of whorls based on concentric circles, like a fingerprint. It opens an area of genuine nanocomposites with novel properties due to AuNPs inside the hair shaft.

View Article and Find Full Text PDF

The asymmetric unit of the title compound, C(8)H(9)Cl(2)NO, contains two crystallographically independent mol-ecules which are connected via an N-H⋯O hydrogen bond . There is aromatic π-π stacking in the crystal, with a centroid-centroid distance between benzene rings of 3.48 (2)Å.

View Article and Find Full Text PDF

In the title compound, C(18)H(16)N(4)O(3)·H(2)O, the dihedral angles between the triazole ring and the phenyl rings are 84.8 (4) and and 39.8 (4)°.

View Article and Find Full Text PDF

The well-defined unnatural dipeptides based on cis-2,5-disubstituted pyrrolidine backbone were synthesized from commercially available starting materials meso-diethyl-2,5-dibromoadipate, (S)-(-)-1-phenylethylamine, and phenylalanine. The configurations of all the chiral centers in these unnatural dipeptides are confirmed by X-ray crystal diffraction analysis.

View Article and Find Full Text PDF
2,2-Dichloro-1-(4-methyl-phen-yl)ethanone.

Acta Crystallogr Sect E Struct Rep Online

January 2011

The mol-ecule of the title compound, C(9)H(8)Cl(2)O, is almost planar: the dihedral angle between the benzene ring and the plane defined by the carbonyl O and ethane C atoms is 15.5 (2)°. The crystal packing is stabilized by inter-molecular C-H⋯O hydrogen bonds.

View Article and Find Full Text PDF
(S)-1-Ferrocenyl-3-hy-droxy-3-phenyl-propan-1-one.

Acta Crystallogr Sect E Struct Rep Online

January 2011

In the title compound, [Fe(C(5)H(5))(C(14)H(13)O(2))], the dihedral angle between the phenyl ring and the unsubstituted cyclo-petadienyl ring is 85.0 (2)°while that between the phenyl ring and the substituted cyclo-petadienyl ring is 83.6 (2)°.

View Article and Find Full Text PDF

Tepoxalin is a potent inhibitor of both the cyclooxygenase and lipoxygenase pathways of the arachidonic acid cascade, as well as a potent anti-inflammatory and control-pain (postoperation, arthritis et. al.) agent.

View Article and Find Full Text PDF

2'-Deoxy-2'-fluoro-2'-C-methyl nucleoside analogue 4 was designed and synthesized. Initial biological studies indicated that this compound showed promising activity against HCV replication.

View Article and Find Full Text PDF
(3S,4S)-1-Benzyl-pyrrolidine-3,4-diol.

Acta Crystallogr Sect E Struct Rep Online

March 2010

In the title compound, C(11)H(15)NO(2), the pyrrolidine ring adapts a twisted envelope conformation and the two hydroxyl groups are arranged in a trans conformation. The crystal packing is stabilized by inter-molecular O-H⋯N and O-H⋯O hydrogen bonds. A weak C-H⋯π inter-action also occurs.

View Article and Find Full Text PDF

In the title compound, C(18)H(20)N(3)O(2), the pyridine and phenyl rings are coplanar [dihedral angle = 3.5 (3)°]. The phenyl ring makes a dihedral angle of 29.

View Article and Find Full Text PDF
2-Benz-yloxy-1-naphthaldehyde.

Acta Crystallogr Sect E Struct Rep Online

February 2009

In the title compound, C(18)H(14)O(2), the dihedral angle between the phenyl and naphthyl ring systems is 21.8 (3)°. The packing of mol-ecules in the crystal structure is stabilized by weak inter-molecular C-H⋯O hydrogen bonds.

View Article and Find Full Text PDF

In the title compound, C(19)H(19)NO(13), one of the two fused furan-ose rings adopts an envelope conformation whereas the other displays a twisted conformation. The crystal structure is stabilized by inter-molecular C-H⋯π inter-actions between a methine H atom and the triacetoxy-phenyl ring of an adjacent mol-ecule, and by weak non-classical inter-molecular C-H⋯O hydrogen bonds.

View Article and Find Full Text PDF