Chengping Wen

Bio-based green solvent mediated disulfide synthesis via thiol couplings free of catalyst and additive

The bio-based green solvent ethyl lactate has been found to be a particularly efficient medium for oxidative coupling reactions of thiols yielding a broad array of disulfides. As a green solvent, ethyl lactate has shown an interesting promotion effect on the transformation by mediating corresponding reactions with high efficiency without using any catalyst or additive.

Synthesis of 3-sulfenylated indoles by a simple NaOH promoted sulfenylation reaction

The C-3 sulfenylation reaction of indoles has been achieved under mild reaction conditions by simply employing NaOH as promoter and thiols as thiolating reagents. This simple method allows for easy and rapid synthesis of various 3-sulfenylated indoles with generally good to excellent yields. Primary attempts in scale-up synthesis give satisfactory result.

Visible‐Light‐Induced CC Bond Cleavage of Enaminones for the Synthesis of 1,2‐Diketones and Quinoxalines in Sustainable Medium

The CC double bond cleavage of enaminones has been realized under ambient conditions through visible‐light catalysis in the presence of Rose Bengal, which leads to the synthesis of a class of 1,2‐diketones without using any metal catalyst. In addition, the one‐pot synthesis of quinoxalines has also been achieved under identical photocatalytic conditions by making use of the in situ generated 1,2‐diketones as intermediates.

Exploration of the serum metabolite signature in patients with rheumatoid arthritis using gas chromatography–mass spectrometry

Rheumatoid arthritis (RA) is a systemic autoimmune disease with complicated pathogeny. There could be obvious alterations of metabolism in the patients with RA and the discovery of metabolic signature may be helpful for the accurate diagnosis of RA. In order to explore the distinctive metabolic patterns in RA patients, a gas chromatography-mass spectrometry (GC-MS) method was employed. Serum samples from 33 RA patients and 32 healthy controls were collected and analyzed. Acquired metabolic data were assessed by the principal component analysis (PCA) and partial least squares discriminant analysis (PLS-DA), and the data analysis results showed RA patients and healthy controls have very different metabolic profiles. Variable importance for project values (VIP) and Students t-test were combined to screen the significant metabolic changes caused by RA. Serums from RA patients were featured by decreased levels of amino acids and glucose, increased levels of fatty acids and cholesterol, which were primarily associated with glycolytic pathway, fatty acid and amino acid metabolism, and other related pathways including TCA cycle and the urea cycle. These preliminary results suggest that GC-MS based metabolic profiling study appears to be a useful tool in the exploration of the metabolic signature of RA, and the revealed disease-associated metabolic perturbations could help to elucidate the pathogenesis of RA and provide a probable aid for the accurate diagnosis of RA.

Alterations of the gut microbiome in Chinese patients with systemic lupus erythematosus

AbstractBackgroundSystemic lupus erythematosus (SLE) in patients from Spain is associated with intestinal dysbiosis. This study explores whether the alteration of the gut microbiome in SLE patients from China is consistent with the intestinal dysbiosis of SLE patients from Spain.ResultsThe depletion of Firmicutes and the enrichment of Bacteroidetes in SLE patients from China were consistent with the SLE patients from Spain. Furthermore, we found that nine genera of gut microbiota were SLE-related microorganisms in Chinese subjects. Genera Rhodococcus, Eggerthella, Klebsiella, Prevotella, Eubacterium, Flavonifractor and Incertae sedis were significantly enriched, while genera Dialister and Pseudobutyrivibrio were significantly depleted in SLE patients. Receiver operating characteristic analysis indicated that the nine genera have the potential to distinguish SLE patients from healthy controls.ConclusionsComparing the dysbiosis of the gut microbiome among SLE patients from China or Spain, may indicate that the gut microbiome profiles of SLE patients are more influenced by disease than ethnicity.

Disulfides as efficient thiolating reagents enabling selective bis-sulfenylation of aryl dihalides under mild copper-catalyzed conditions

Selective bis-sulfenylation reactions of aryl dihalides have been achieved by copper-catalyzed C–S coupling reactions under mild conditions of refluxing EtOH (80 °C). Employment of disulfides as thiolating reagents enables the production of various bis(phenylthio)benzenes with excellent selectivity, and no products from mono C–S coupling are isolated.

Quantitative metagenomics reveals unique gut microbiome biomarkers in ankylosing spondylitis

BackgroundThe assessment and characterization of the gut microbiome has become a focus of research in the area of human autoimmune diseases. Ankylosing spondylitis is an inflammatory autoimmune disease and evidence showed that ankylosing spondylitis may be a microbiome-driven disease.ResultsTo investigate the relationship between the gut microbiome and ankylosing spondylitis, a quantitative metagenomics study based on deep shotgun sequencing was performed, using gut microbial DNA from 211 Chinese individuals. A total of 23,709 genes and 12 metagenomic species were shown to be differentially abundant between ankylosing spondylitis patients and healthy controls. Patients were characterized by a form of gut microbial dysbiosis that is more prominent than previously reported cases with inflammatory bowel disease. Specifically, the ankylosing spondylitis patients demonstrated increases in the abundance of Prevotella melaninogenica, Prevotella copri, and Prevotella sp. C561 and decreases in Bacteroides spp. It is noteworthy that the Bifidobacterium genus, which is commonly used in probiotics, accumulated in the ankylosing spondylitis patients. Diagnostic algorithms were established using a subset of these gut microbial biomarkers.ConclusionsAlterations of the gut microbiome are associated with development of ankylosing spondylitis. Our data suggest biomarkers identified in this study might participate in the pathogenesis or development process of ankylosing spondylitis, providing new leads for the development of new diagnostic tools and potential treatments.

Effect of a traditional Chinese medicine prescription Quzhuotongbi decoction on hyperuricemia model rats studied by using serum metabolomics based on gas chromatography-mass spectrometry

Morbidity of hyperuricemia has constantly increased in population in decades, and hyperuricemia has proved to be an important risk factor for gout, cardiovascular diseases and others. Many urate-lowering drugs have unfavorable side effects and drug interactions. Quzhuotongbi decoction (QZTBD) is an empirical traditional Chinese medicine prescription for clinical therapy of hyperuricemia without serious adverse effects. In the study, we investigated the effects of QZTBD on urate and other metabolites in the sera of hyperuricemia model rats. Hyperuricemia model was established by orally administering yeast extract paste, and allopurinol served as a positive control drug. Serum metabolomics was performed by using a gas chromatography-mass spectrometry (GC-MS) method. Students t-test and the principal component analysis (PCA) were employed to find the metabolic perturbations in hyperuricemia model rats. The levels of urate, lactate, pyruvate and ornithine were significantly increased, and xanthine, glyconic acids (ribonate, galactonate), amino acids (aspartate, proline, glutamine, serine, pyroglutamate, glutamate) and glucose were down-regulated greatly in the model rats. It demonstrated that nucleotide metabolism, amino acid metabolism and glycolytic pathway were disturbed by yeast administration. An orthogonal signal correction-partial least-squares discriminant analysis (OSC-PLS DA) was performed to assess the effects of yeast administering and drug treatment. 11 significantly distinctive metabolites among four groups were defined according to the variable importance for project values (VIP>1) and univariate ANOVA (p value<0.05). As compared to the model rats, the serum uric acid levels were lowered markedly under the treatment of allopurinol or QZTBD. Aspartate and glutamine involved in purine metabolism, were raised to normal level as well. The different influences on xanthine, glutamate pyroglutamate and galactonate suggested there were different mechanisms of two drugs in urate-lowering therapy. Our finding proved that QZTBD can efficiently lower the level of serum uric acid in a different way from allopurinol, which suggested that QZTBD based on the theory of TCM could be an effective therapeutic option for hyperuricemia.

Lipidomics Revealed Idiopathic Pulmonary Fibrosis-Induced Hepatic Lipid Disorders Corrected with Treatment of Baicalin in a Murine Model

Idiopathic pulmonary fibrosis (IPF) is a fatal lung disease. The current standard treatment with glucocorticoids (GCs) leads to many adverse effects, and its effectiveness is questionable. Thus, it is critical and urgent to find new drug(s) for treatment of IPF. Baicalin (BAI) is an attractive candidate for this purpose. Herein, utilizing shotgun lipidomics, we revealed that IPF could lead to a lipid disorder of the liver in an animal model induced by bleomycin and confirmed through histopathological studies of the lung. Lipidomics further demonstrated that this disorder could virtually be corrected after treatment with BAI, but not with dexamethasone (DEX) (a commonly used GC for treatment of IPF). In contrast, the treatment with DEX did not improve IPF but led to tremendous alterations in hepatic lipidomes and accumulation of fat in the liver, which was very different from the lipid disorder induced by IPF. The underpinning mechanisms of the IPF-resultant lipid disorder and DEX-induced lipotoxicity as revealed by shotgun lipidomics were extensively discussed. Taken together, the current study showed that IPF could lead to hepatic lipid disorder, which can be treated with BAI, and demonstrated that lipidomics could be a powerful tool for drug screening.

Regioselective three-component reactions of enaminones, 2-aminopyridines and enals for the synthesis of 1,2-dihydropyridines

A three-component synthetic method involving the assembly of enals, N,N-disubstituted enaminones and 2-aminopyridines has been designed, which leads to the facile and regioselective synthesis of 1,2-dihydropyridines (1,2-DHPs) with broad scope and generally good yields in the presence of simple acid catalysts.