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1.
Biomed Environ Sci ; 37(4): 377-386, 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38727160

RESUMO

Objective: This study aimed to investigate the lipid-lowering activity of LFBEP-C1 in high glucose-fed Caenorhabditis elegans (C. elegans). Methods: In this study, the fermented barley protein LFBEP-C1 was prepared and tested for its potential anti-obesity effects on C. elegans. The worms were fed Escherichia coli OP50 ( E. coli OP50), glucose, and different concentrations of LFBEP-C1. Body size, lifespan, movement, triglyceride content, and gene expression were analyzed. The results were analyzed using ANOVA and Tukey's multiple comparison test. Results: Compared with the model group, the head-swing frequency of C. elegans in the group of LFBEP-C1 at 20 µg/mL increased by 33.88%, and the body-bending frequency increased by 27.09%. This indicated that LFBEP-C1 improved the locomotive ability of C. elegans. The average lifespan of C. elegans reached 13.55 days, and the body length and width of the C. elegans decreased after LFBEP-C1 intake. Additionally, LFBEP-C1 reduced the content of lipid accumulation and triglyceride levels. The expression levels of sbp-1, daf-2, and mdt-15 significantly decreased, while those of daf-16, tph-1, mod-1, and ser-4 significantly increased after LFBEP-C1 intake. Changes in these genes explain the signaling pathways that regulate lipid metabolism. Conclusion: LFBEP-C1 significantly reduced lipid deposition in C. elegans fed a high-glucose diet and alleviated the adverse effects of a high-glucose diet on the development, lifespan, and exercise behavior of C. elegans. In addition, LFBEP-C1 regulated lipid metabolism mainly by mediating the expression of genes in the sterol regulatory element-binding protein, insulin, and 5-hydroxytryptamine signaling pathways.


Assuntos
Caenorhabditis elegans , Hordeum , Metabolismo dos Lipídeos , Animais , Caenorhabditis elegans/efeitos dos fármacos , Caenorhabditis elegans/metabolismo , Hordeum/química , Metabolismo dos Lipídeos/efeitos dos fármacos , Fermentação , Extratos Vegetais/farmacologia , Extratos Vegetais/química , Lactobacillus plantarum , Proteínas de Caenorhabditis elegans/metabolismo , Proteínas de Caenorhabditis elegans/genética , Proteínas de Bactérias/metabolismo , Proteínas de Bactérias/genética
2.
Acc Chem Res ; 56(3): 332-349, 2023 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-36689780

RESUMO

ConspectusCatalytic asymmetric hydrogenation is one of the most reliable, powerful, and environmentally benign methods for the synthesis of chiral molecules with high atom economy and has been successfully applied in the industrial production of pharmaceuticals, agrochemicals, and fragrances. The key to achieving highly efficient and highly enantioselective hydrogenation reactions is the design and synthesis of chiral catalysts.Our recent studies involving iridium complexes of bidentate chiral spiro aminophosphine ligands (Ir-SpiroAP) have revealed that adding another coordinating group on the nitrogen atom to form a tridentate ligand can provide catalysts with markedly higher stability, enantioselectivity, and efficiency. Specifically, chiral Ir-SpiroAP catalysts bearing an added pyridine group (designated Ir-SpiroPAP) exhibit high activity and excellent enantioselectivity in the asymmetric hydrogenation of a wide range of carbonyl compounds, including aryl ketones, ß- and δ-ketoesters, α,ß-unsaturated ketones and esters, and racemic α-substituted lactones, as well as highly electron-deficient alkenes such as α,ß-unsaturated malonates and analogues. The efficiency of the Ir-SpiroPAP catalysts is extremely high: in the hydrogenation of aryl ketones, turnover numbers reach 4.5 million, which is the highest value reported to date for a molecular catalyst. Moreover, when a thioether or a bulky triarylphosphine group is added to afford tridentate ligands designated SpiroSAP and SpiroPNP, respectively, the resulting iridium catalysts show high efficiency and enantioselectivity for asymmetric hydrogenation of ß-alkyl-ß-ketoesters and dialkyl ketones, which are challenging substrates. Furthermore, chiral spiro catalysts containing an added oxazoline moiety (Ir-SpiroOAP) show high enantioselectivity for asymmetric hydrogenation of α-keto amides and racemic α-aryloxy lactones. The above-described catalysts have been used for enantioselective synthesis of chiral pharmaceuticals and other bioactive compounds.We have shown that chiral spiro ligands that combine a rigid skeleton with tridentate coordination stabilize iridium catalysts. The careful tailoring of the substituents on the ligand creates a chiral environment around the active metal center of the catalyst that can precisely discriminate between the two faces of a substrate carbonyl group. These factors are key for controlling the activity, enantioselectivity, and turnover numbers of asymmetric hydrogenation catalysts. We expect that catalysts based on iridium, and other transition metals, coordinated by tridentate chiral ligands with a rigid skeleton will find more applications in asymmetric hydrogenation and other asymmetric transformations.

3.
Org Lett ; 24(28): 5161-5165, 2022 07 22.
Artigo em Inglês | MEDLINE | ID: mdl-35816023

RESUMO

Herein, we report the first enantioselective total synthesis of the highly complex hamigeran diterpenoid (-)-hamigeran F and its rearrangement product. The synthetic strategy features key steps of asymmetric hydrogenation, Horner-Wadsworth-Emmons olefination, and intramolecular Friedel-Crafts acylation to construct the [6,6,5]-tricyclic skeleton bearing three consecutive stereocenters, a sequence of steps involving Rosenmund reduction, Wittig reaction, dihydroxylation to assemble the α-acetoxy ketone group, and an intramolecular aldol reaction to build the tetracyclic core structure.


Assuntos
Diterpenos , Cetonas , Acilação , Hidrogenação , Estrutura Molecular , Estereoisomerismo
4.
Phytomedicine ; 102: 154194, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35660348

RESUMO

BACKGROUND: Uncontrolled inflammation causes health problems. Extracellular signal-regulated kinase (ERK) phosphorylates signal transducer and activator of transcription 3 (STAT3) at Ser727, resulting in inflammation. The leaf of Vernonia amygdalina (VA) is a medicinal herb for managing inflammation-associated diseases. Oral administration or topical application of VA leaf extract exerts anti-inflammatory effects in rat models. However, the anti-inflammatory mechanisms of the herb are not fully understood. PURPOSE: In this study, we aimed to investigate the involvement of ERK/STAT3 (Ser727) signaling in the anti-inflammatory effects of an ethanolic extract of VA leaves. STUDY DESIGN AND METHODS: Extracts of VA leaves were prepared with different concentrations of ethanol. A LPS-stimulated RAW264.7 cell model was used for in vitro assays, and a TPA (12-O-tetradecanoylphorbol-13-acetate)-induced ear edema mouse model was employed for in vivo assays. The 95% ethanol extract of VA leaves (VAE) exerted the strongest inhibitory effect on nitric oxide (NO) production in LPS-stimulated macrophages; thus it was selected for use in this study. Hematoxylin and eosin (H&E) staining was used to examine pathological conditions of mouse ear tissues. Griess reagent was employed to examine NO generation in cell cultures. Immunoblotting and ELISA were used to examine protein levels, and RT-qPCR was employed to examine mRNA levels. RESULTS: Topical application of VAE ameliorated mouse ear edema induced by TPA. VAE suppressed the phosphorylation of ERK (Thr202/Tyr204) and STAT3 (Ser727); and decreased protein levels of inducible nitric oxide synthase (iNOS), cyclooxygenase-2 (COX-2), interleukin (IL)-6, IL-1ß and tumor necrosis factor-α (TNF-α) in the mouse ear tissues and in LPS-stimulated RAW 264.7 cells. VAE also inhibited NO production, and lowered mRNA levels of IL-6, IL-1ß and TNF-α in the macrophages. CONCLUSIONS: VAE ameliorates TPA-induced mouse ear edema. Suppression of ERK/STAT3 (Ser727) signaling is involved in VAE's anti-inflammatory effects. These novel data provide further pharmacological justifications for the medicinal use of VA in treating inflammation-associated diseases, and lay the groundwork for developing VAE into a new anti-inflammatory agent.


Assuntos
Fator de Transcrição STAT3 , Vernonia , Animais , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/uso terapêutico , Edema/tratamento farmacológico , Etanol , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Inflamação/induzido quimicamente , Inflamação/tratamento farmacológico , Interleucina-6/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , NF-kappa B/metabolismo , Óxido Nítrico/metabolismo , Óxido Nítrico Sintase Tipo II/metabolismo , Extratos Vegetais/uso terapêutico , RNA Mensageiro , Ratos , Fator de Transcrição STAT3/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
5.
Org Lett ; 24(19): 3477-3481, 2022 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-35522037

RESUMO

An enantioselective total synthesis of the alleged structure of (+)-fimbricalyxoid A is reported. The synthetic strategy features a pyridine-N-oxidate-mediated SN2' reaction to introduce an oxygen functionality at position C3 of the A-ring and a sequential three-step process via the cleavage of the C-O bonds and hemiketalization to form the 3,20-oxybridge. With this strategy, the target molecule was synthesized in 19% overall yield and 12 steps from our previously synthesized cis-fused octahydrophenanthrene (+)-6.

6.
Org Lett ; 24(14): 2590-2595, 2022 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-35357843

RESUMO

A three-step process for the enantioselective assembly of cis-fused octahydrophenanthrenes with a quaternary stereocenter is reported. This synthetic strategy relies on a regioselective γ-alkylation, a one-pot sequence of asymmetric hydrogenation and oxidation, and an intramolecular enolate arylation to facilitate the rapid and enantioselective construction of cis-fused octahydrophenanthrene scaffolds with an arylated all-carbon quaternary stereocenter concisely and efficiently.


Assuntos
Carbono , Alquilação , Oxirredução , Estereoisomerismo
7.
Org Lett ; 23(22): 8883-8887, 2021 11 19.
Artigo em Inglês | MEDLINE | ID: mdl-34709843

RESUMO

An efficient asymmetric hydrogenation of racemic α-aryl-ß-ethoxycarbonyl cyclopentanones via dynamic kinetic resolution is reported. Via catalysis by a chiral iridium Ir-SpiroPAP catalyst, a range of racemic α-aryl-ß-ethoxycarbonyl cyclopentanones were hydrogenated to the corresponding ester-functionalized chiral 2-arylcyclopentanols with three contiguous stereocenters in high yields with excellent enantio- and diastereoselectivities. This method was successfully applied in the enantioselective synthesis of cyclopentane-based γ-amino ester/alcohol derivatives and phenylpropanoid (+)-burmaniol A.

8.
Chem Sci ; 12(22): 7793-7799, 2021 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-34168833

RESUMO

An iridium catalyzed asymmetric hydrogenation of racemic exocyclic γ,δ-unsaturated ß-ketoesters via dynamic kinetic resolution to functionalized chiral allylic alcohols was developed. With the chiral spiro iridium catalysts Ir-SpiroPAP, a series of racemic exocyclic γ,δ-unsaturated ß-ketoesters bearing a five-, six-, or seven-membered ring were hydrogenated to the corresponding functionalized chiral allylic alcohols in high yields with good to excellent enantioselectivities (87 to >99% ee) and cis-selectivities (93 : 7 to >99 : 1). The origin of the excellent stereoselectivity was also rationalized by density functional theory calculations. Furthermore, this protocol could be performed on gram scale and at a lower catalyst loading (0.002 mol%) without the loss of reactivity and enantioselectivity, and has been successfully applied in the enantioselective synthesis of chiral carbocyclic δ-amino esters and the ß-galactosidase inhibitor isogalactofagomine.

9.
Org Lett ; 23(13): 5153-5157, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34152152

RESUMO

An efficient asymmetric hydrogenation of racemic γ-substituted cyclic ß-ketoesters via dynamic kinetic resolution to provide chiral cyclic ß-hydroxy esters with three contiguous stereocenters is reported. Using a chiral spiro iridium catalyst (R)-5 (Ir-SpiroSAP), a series of racemic γ-aryl/alkyl substituted cyclic ß-ketoesters were hydrogenated to the corresponding chiral cyclic ß-hydroxy esters in high yields (84-97%) with good to excellent enantioselectivities (69->99% ee) and cis,cis-selectivities (up to >99:1).

10.
Mitochondrial DNA B Resour ; 6(6): 1781-1783, 2021 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-34104773

RESUMO

Thyrsostachys is oligotypic genus of Bambusinae, while its phylogenetic position had been unclear. Here, the complete plastid genome of the type species, T. siamensis, was sequenced and analyzed in this work. The complete genome is a typical quadripartite structure with 139,522 bp in length, comprising of a large single-copy region (LSC, 83,032 bp), a small single-copy region (SSC, 12,892 bp), and a pair of invert repeats regions (IR, 21,799 bp). The genome contains 138 genes, 89 protein-coding genes, 41 tRNA genes, and 8 rRNA genes. The GC content of genome was 38.9%. Phylogenetic analysis indicated T. siamensis was sister to Dendrocalamus birmanicus within Bambusinae.

11.
Org Lett ; 23(9): 3593-3598, 2021 05 07.
Artigo em Inglês | MEDLINE | ID: mdl-33872510

RESUMO

A protocol of iridium catalyzed asymmetric hydrogenation of 4-alkyl substituted 3-ethoxycarbonyl quinolin-2-ones and coumarins has been reported, providing a wide range of chiral dihydroquinolin-2-ones and dihydrocoumarins in high yields with excellent enantioselectivities (up to 99% ee) and high turnover numbers (up to 28 000). This efficient protocol was successfully applied for the synthesis of MPR3160 and the key chiral intermediate of R-106578.

12.
Org Lett ; 23(5): 1675-1680, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33599130

RESUMO

Herein, we report a practical method for efficient asymmetric hydrogenation of ß-aryl alkylidene malonates. With a site-specifically tailored chiral spiro iridium catalyst, a series of ß-aryl alkylidene malonate esters were hydrogenated to afford chiral malonate esters with good to excellent enantioselectivities (up to 99% ee) and high turnover numbers (up to 19000). The results showed that installing an ester group in α,ß-unsaturated carboxylic esters significantly increased the efficiency of their asymmetric hydrogenation reactions.

13.
Org Lett ; 23(5): 1616-1620, 2021 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-33570959

RESUMO

A ruthenium-catalyzed asymmetric hydrogenation method for the synthesis of functionalized ß-aryl cyclohexanols is described. With chiral spiro ruthenium catalyst (Ra,S,S)-5c, a series of racemic α-aryl cyclohexanones bearing a ß-monoethylene ketal group were hydrogenated to the corresponding functionalized ß-aryl cyclohexanols in high yields with enantioselectivity of up to 99% ee via a dynamic kinetic resolution. This protocol can be conducted on a decagram scale and provide potential approaches for the synthesis of optically active and densely functionalized aryl cyclohexanols.

14.
Angew Chem Int Ed Engl ; 60(6): 2948-2951, 2021 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-33094547

RESUMO

A highly enantio- and regioselective hydrosulfonylation of 1,3-dienes with sulfonyl hydrazides has been realized by using a palladium catalyst containing a monodentate chiral spiro phosphoramidite ligand. The reaction provided an efficient approach to synthetically useful chiral allylic sulfones. Mechanistic studies suggest that the reaction proceeds through the formation of an allyl hydrazine intermediate and subsequent rearrangement to the chiral allylic sulfone product. The transformation of the allyl hydrazine intermediate to the product is the enantioselectivity-determining step.

15.
Org Lett ; 22(19): 7526-7530, 2020 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-32937077

RESUMO

Herein we report the first enantioselective total syntheses of pentacyclic homoproaporphine alkaloids by means of a route, which includes a tandem retro-oxa-Michael addition and nucleophilic substitution to generate the oxa-benzobicyclco[3.3.1]nonane core structure, a Pictet-Spengler cyclization to construct the fused B and C rings, and sequential Baeyer-Villiger oxidation and pinacol-type cyclization to install the hydroxyl-lactol moiety of D ring. With this unified route, six pentacyclic homoproaporphine alkaloids have been synthesized enantioselectively.

16.
Curr Med Sci ; 40(4): 662-670, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-32862376

RESUMO

In various autoimmune diseases, Galecin-9 (Gal-9) has been shown to regulate the T-cell balance by decreasing Th1 and Th17, while increasing the number of regulatory T cells (Tregs). However, the role of Gal-9 in the patients with acute coronary syndrome (ACS) and chronic kidney disease (CKD) remains unclear. This study aims to measure the Gal-9 levels in serum and peripheral blood mononuclear cells (PBMCs) in patients with ACS plus CKD and examine their clinical implication. The serum levels of Gal-9 were determined by enzyme-linked immunosorbent assay (ELISA), the expression levels of Gal-9, Tim-3, and Foxp3 mRNA in PBMCs were detected by real-time reverse transcription-polymerase chain reaction (RT-PCR), and the expression of Gal-9 on the surface of PBMCs and in PBMCs was analyzed by flow cytometry. Furthermore, the correlation of serum Gal-9 levels with anthropometric and biochemical variables in patients with ACS plus CKD was analyzed. The lowest levels of Gal-9 in serum and PBMCs were found in the only ACS group, followed by the ACS+CKD group, and the normal coronary artery (NCA) group, respectively. Serum Gal-9 levels were increased along with the progression of glomerular filtration rate (GFR) categories of G1 to G4. Additionally, serum Gal-9 levels were negatively correlated with high-sensitivity C-reactive protein (hs-CRP), estimated GFR (eGFR), and lipoprotein(a), but positively with creatinine, age, osmotic pressure, and blood urea nitrogen (BUN). Notably, serum Gal-9 was independently associated with hs-CRP, osmotic pressure, and lipoprotein(a). Furthermore, serum Gal-9 levels were elevated in patients with type 2 diabetes (T2DM) and impaired glucose tolerance (IGT) in ACS group. It was suggested that the levels of Gal-9 in serum and PBMCs were decreased in patients with simple ACS and those with ACS plus CKD, and hs-CRP, eGFR, osmotic pressure and T2DM may have an influence on serum Gal-9 levels.


Assuntos
Síndrome Coronariana Aguda/metabolismo , Regulação para Baixo , Galectinas/sangue , Galectinas/genética , Insuficiência Renal Crônica/metabolismo , Síndrome Coronariana Aguda/genética , Síndrome Coronariana Aguda/fisiopatologia , Adulto , Idoso , Comorbidade , Feminino , Fatores de Transcrição Forkhead , Taxa de Filtração Glomerular , Receptor Celular 2 do Vírus da Hepatite A/genética , Humanos , Masculino , Pessoa de Meia-Idade , Receptores Imunológicos/sangue , Insuficiência Renal Crônica/genética , Insuficiência Renal Crônica/fisiopatologia
17.
Food Chem ; 316: 126269, 2020 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-32044701

RESUMO

This study investigated the comparative effects of boiling, roasting, deep-frying methods on the content of nutritional and potentially harmful components in peanuts. After cooking, the contents of total reducing sugar, sucrose, unsaturated fatty acids and almost all individual amino acids were reduced. Free methionine disappeared after heating processing, whereas fructose, starch, cis-palmitoleic acid and saturated fatty acids were increased in processed samples. Micronutrients including flavonoids and phenolic reduced significantly after boiling process but increased after roasting process. Both of frying and roasting promoted the formation of potentially harmful components including HMF, acrylamide and furan. The overall compositional difference between samples were further displayed and identified by a combination application of HCA and PCA, which showed that the roasting and frying process had a significant impact on the nutritional composition of peanuts.


Assuntos
Arachis/química , Culinária/métodos , Carboidratos/química , Temperatura Alta , Lipídeos/química , Proteínas de Plantas/química
18.
Org Lett ; 22(3): 818-822, 2020 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-31961159

RESUMO

A highly efficient asymmetric hydrogenation of γ- and δ-ketoacids was developed by using a chiral spiro iridium catalyst (S)-1a, affording the optically active γ- and δ-hydroxy acids/lactones in high yields with excellent enantioselectivities (up to >99% ee) and turnover numbers (TON up to 100000). This protocol provides an efficient and practical method for enantioselective synthesis of Ezetimibe.

19.
Org Lett ; 21(11): 4111-4115, 2019 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-31124683

RESUMO

A protocol for highly enantioselective hydrogenation of racemic α-arylamino lactones with catalysis by site-specifically modified chiral spiro iridium complexes has been developed. With the optimized catalyst, racemic α-arylamino-γ-lactones and α-arylamino-δ-lactones could be hydrogenated to the corresponding chiral 2-amino diols with good to excellent enantioselectivities.

20.
Org Lett ; 21(7): 2369-2373, 2019 04 05.
Artigo em Inglês | MEDLINE | ID: mdl-30883133

RESUMO

An iterative protocol was developed for highly diastereo- and enantioselective construction of high-order 1,3-polyols via iridium-catalyzed asymmetric hydrogenation of ß-alkyl-ß-keto esters. The protocol involves four operations-asymmetric hydrogenation, hydroxy protection, ester hydrolysis, and C-acylation-and the catalyst loading can be as low as 0.005 mol %. The configurations of all stereogenic centers of 1,3-polyols are controlled by the catalyst. By the use of this protocol, a formal total synthesis of the polyketide cyanolide A was achieved with high diastereoselectivity and enantioselectivity.

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