Activated Carbonyl Compounds Research Articles

Green Synthesis of New Spiropyrrole Derivatives by Employing Activated Carbonyl Compounds and Graphen Oxide Decorated on Ag@CuO/ZnO NPs or CuO/ZnO NPs: Theoretical and Biological Study

ABSTRACTThis study focused on investigating the synthesis of new spiropyrrole derivatives with high yields. The two nanocatalyst CuO/ZnO@Graphen Oxide nanocomposites (CuO/ZnO@GO NCs) and Ag/CuO/ZnO@Graphen Oxide (Ag@CuO/ZnO@GO NCs) were employed in a multicomponent reaction at room temperature to synthesize new compounds. The reaction involved isatins, N‐alkyl isatins, and ninhydrin as activated carbonyl compounds, ammonium acetate, ethyl 2‐arylamino‐4‐dioxo‐4‐arylbutanoates, hydrazonoyl chloride, or ethylbromopyruvate in water. Also, the catalytic activity of the green synthesized CuO/ZnO@GO and Ag@CuO/ZnO@GO was evaluated in the reduction of organic pollutants such as 4‐nitrophenol (4‐NP) in water at mild conditions. The results indicated that the biosynthesized MNCs have very high and effective catalytic activity for organic pollutants within a few seconds. The newly synthesized spiro compounds demonstrate antioxidant activity as a result of two assessment processes conducted by its NH group. In addition, the antibacterial activity of newly created spiro compounds was assessed using a disk distribution method, involving two types of Gram‐negative bacteria. These compounds were found to limit the growth of Gram‐positive bacteria as well. Also, to better understand the reaction mechanism, density functional theory (DFT)–based quantum chemical methods have been applied. The advantages of this technology encompass rapid response times, high product yields, and uncomplicated catalyst and product separation via simple procedures.

Domino reactions of chromones with activated carbonyl compounds.

Domino reactions of chromones with activated carbonyl compounds, such as dimethyl acetone-1,3-dicarboxylate and 1,3-diphenylacetone, and with 1,3-bis(silyloxy)-1,3-butadienes, electroneutral equivalents of 1,3-dicarbonyl dianions, allow for a convenient synthesis of a great variety of products. The regioselectivity and course of the reaction depends of the substituent located at carbon C3 of the chromone moiety and also on the type of nucleophile employed.

Asymmetric Synthesis of 3-Pyrrole Substituted β-Lactams Through p-Toluene Sulphonic Acid-catalyzed Reaction of Azetidine-2,3-diones with Hydroxyprolines

Aims: The aim of this study is to investigate the p-toluene sulphonic acid (p-Ts.OH)- catalyzed reaction of racemic-azetidine-2,3-diones with enantiomerically pure cis and trans-4- hydroxy-L-proline in refluxing ethanol culminating in a synthesis of substituted novel 3-(pyrrol-1- yl)-azetidin-2-ones at the C-3 position. Methods: This work describes an alternative synthetic route enabling the tandem transformation of proline to pyrrole, followed by intramolecular chirality transfer to the β -lactams ring. Results: All four diastereomers of 3-(pyrrol-1-yl)-azetidin-2-ones could be achieved in good to excellent yield with high diastereoselectivity in a single-pot operation. Conclusion: This method can be applied to other activated carbonyl compounds and functionalized pyrroles can be obtained through an expeditious process.

Synthesis and evaluation of the antioxidant activity of new spiro-1,2,4-triazine derivatives applying Ag/Fe3O4/CdO@MWCNT MNCs as efficient organometallic nanocatalysts.

We applied the Petasites hybridus rhizome water extract as green media so that Ag/Fe3O4/CdO@ multi-walled carbon nanotubes magnetic nanocomposites (Ag/Fe3O4/CdO@MWCNTs MNCs) could be prepared. We also evaluated its activity by using in the one-pot multicomponent reaction of acetophenones, diethyl oxalate, ammonium acetate, and activated carbonyl compounds such as ninhydrin, isatin and acenaphthylene-1,2-dione, and malononitrile and hydrazoyl chlorides in an aqueous medium at room temperature for the generation of spiro-1,2,4-triazines as new derivatives with tremendous output. Moreover, reducing organic pollutants from 4-nitrophenol (4-NP) was carried out by generating Ag/Fe3O4/CdO@MWCNTs in water at room temperature. The results displayed that Ag/Fe3O4/CdO@MWCNTs reduced pollutants of organic compounds in a short time. The synthesized spiro-1,2,4-triazines have NH and OH functional groups having acidic hydrogen with high antioxidant power. Also, the spiro-1,2,4-triazines exhibited antimicrobial ability. For this purpose, the disk diffusion method was applied and two kinds of bacteria, Gram-positive and Gram-negative, were employed for the analysis. Furthermore, we applied functional theory-based quantum chemical methods in order to better understand reaction mechanism density. To generate spiro-1,2,4-triazines, the applied process showed many properties such as reactions with short time, products with good yields, and simple extraction of catalyst from a mixture of reactions.

Research Progress of Active Carbonyl Compounds Produced by Oxidantion of Fats in Food

Research Progress of Active Carbonyl Compounds Produced by Oxidantion of Fats in Food

On the Reaction of 2-Alkanoylnaphthohydroquinones with Hydroxylamine: Access to Cytotoxic 2-(Hydroxyamino)-1,4-naphthoquinone and Their 3-(Hydroxyimino)alkyl Analogous

Oximes are known for their anti-inflammatory, antimicrobial, antioxidant, and anticancer activities. Frequently, modification of biologically active carbonyl compounds into oximes leads to increased activity. The present study reports the reactivity of 2-alkanoylnaphthohydroquinones against hydroxylamine under aerial conditions. Results show that, depending on the structure of the hydroquinones, the reaction proceeds through two different chemical pathways to produce 2-(hydroxyamino)-1,4-naphthoquinone and their C-3 (hydroxyimino)alkyl derivatives. Both the formation of the quinoid compounds under aerial oxidation and C-C cleavage reactions of hemiaminal intermediates are discussed. In vitro screening of the substituted 1,4-naphthoquinones on a panel of cancer cells reveals moderate cytotoxic activities. Compound 19, 2-(hydroxyamino)-1,4-naphthoquinone, stands out by its anticancer potency against prostate cancer cells as shown by the lowest IC50 value (8.08 μM) and the best selectivity index (3.90).

Divergent Annulation of Spiro[indoline‐pyran] and Fused (Epoxyetheno)indeno‐Furan from 1,2‐Diketone and 1‐Cyanoketone

AbstractA simple and efficient method for the construction of spiro[indoline‐pyran] and fused (epoxyetheno)indeno[1,2‐b]furan compounds from 1‐cyanoketones and 1,2‐diketone has been developed. The synthesis proceeded via the Knoevenagel and Michael adduct through intramolecular/Paal‐Knorr cyclization under similar reaction condition. The less commonly used 1‐cyanoketones and active carbonyl compounds served as the indole containing pyran and bicyclic furan source for the preparation of a new series of heterocyclic compounds. This heterocyclic structure allows one and more than one tetra‐substituted carbon center and sequential hexa‐ and penta‐cyclic core under very mild conditions and shows excellent chemo and regioselectivity. In addition, the synthesis of spiro[indoline‐pyran] and (epoxyetheno)indeno[1,2‐b]furan was demonstrated in a gram scale.

Pd-Catalyzed Enantioselective (3+2)-Cycloaddition of Vinyl-Substituted Oxyallyl Carbonates with Isocyanates and Ketones.

The vinyl-substituted oxyallyl carbonates were exploited as a new C,O-dipole for enantioselective Pd-catalyzed (3+2) cycloaddition. The corresponding oxyallyl-Pd species was weakly nucleophilic to react with activated carbonyl compounds, affording multisubstituted and enantioenriched oxazolidinones and 1,3-dioxolanes with a high degree of chemo- and stereoselectivity. The synthetic transformations of oxazolidinone product were carried out to build enantioenriched α-chiral aminoketone and epoxy derivatives.

Poly(N-vinylimidazole): A biocompatible and biodegradable functional polymer, metal-free, and highly recyclable heterogeneous catalyst for the mechanochemical synthesis of oximes.

The catalytic activity of poly(N-vinylimidazole), a biocompatible and biodegradable synthetic functional polymer, was investigated for the synthesis of oximes as an efficient, halogen-free, and reusable heterogeneous catalyst. The corresponding oximes were afforded in high to excellent yields at room temperature and in short times using the planetary ball mill technique. Some merits, such as the short reaction times and good yields for poorly active carbonyl compounds, and avoiding toxic, expensive, metal-containing catalysts, and hazardous and flammable solvents, can be mentioned for the current catalytic synthesis of the oximes. Furthermore, the heterogeneous organocatalyst could be easily separated after the reaction, and the regenerated catalyst was reused several times with no significant loss of its catalytic activity.

THE IMPACT OF METFORMIN AND ROSUVASTATIN ON THE MARKERS OF OXIDATIVE STRESS, GLYCEMIC CONTROL, AND LIPID PROFILE IN RATS WITH STREPTOZOTOCIN-NICOTINAMIDE-INDUCED DIABETES AFTER ACUTE INTRACEREBRAL HEMORRHAGE

Hyperproduction of highly active carbonyl compounds and reactive oxygen species initiates the development of oxidative stress in various pathological conditions and protein carbonylation is considered to be one of the key factors in the progression of diabetes mellitus and associated complications. This comparative research aimed to study the effect of metformin and rosuvastatin on the levels of biochemical markers of oxidative stress, glycemic control, and lipid profile in rats with type 2 diabetes mellitus (T2DM) complicated by a brain hemorrhage.T2DM was simulated with a single intraperitoneal injection of nicotinamide and streptozotocin (NA/STZ) to male Wistar rats (n=38). Intracerebral hemorrhage (ICH) was induced by microinjection of 1 μL of bacterial collagenase 0.2 IU/μL into the striatum. Animals were randomized into 5 groups: negative control, intact rats; positive control 1, NA/STZ; positive control 2, NA/STZ+ICH; metformin, 250 mg/kg +NA/STZ+ICH; rosuvastatin, 15 mg/kg+NA/STZ+ICH. Drug effects were assessed by the area under the glycemic curve (AUC), the content of glucose, glycated hemoglobin (HbA1c), total cholesterol (TC), triglyceride (TG), high-density lipoprotein (HDL), homocysteine (Hcy), advanced glycation end products (AGEs), and the markers of oxidative modification of proteins – aldehyde- and ketonephenylhydrazones (APH/KPH) in blood serum.It was found that brain hemorrhage in rats with T2DM can intensify the manifestations of oxidative modification of molecules and worsen glycemic control and lipid profile. Under these conditions, rosuvastatin improved lipid metabolism and reduced the levels of AGEs by 35.1% but did not affect glycemia and content of APH/KPH. Metformin reduced oxidative stress (AGEs by 35.4%, KPH by 21.2%) as well as improved both glycemic status and lipid profile (TG level by 20.2%, TG/HDL ratio by 31.9%). Both drugs did not produce any effect on Hcy level.Thus, metformin in conditions of T2DM complicated by acute ICH has advantages over rosuvastatin in relation to the markers of oxidative modification and glycemic control.

TFA-mediated synthesis of functionalized pyrano[2,3-c]pyrazoles from pyrazol-3-ones, active carbonyl compounds and tert-BuOH.

Functionalized pyrano[2,3-c]pyrazoles were synthesized from 2,4-dihydro-3H-pyrazol-3-ones, active carbonyl compounds and tert-BuOH in the presence of trifluoroacetic acid at 65°C. These reactions are proceeded by acid catalyzed generation of isobutylene from tert-BuOH for LUMOdiene-controlled inverse [4 + 2] cycloaddition reaction with in situ-generated vinylidenepyrazolones.

Water Extract of Tamarindus Indica Seed Ash: An Agro-Waste Green Medium for One-Pot Three-Component Approach for the Synthesis of 4H-Pyran Derivatives

Herein, a new, bio-mass derived sustainable feedstock was employed for the synthesis of 4H-pyran derivatives. In context of this, water extract of tamarindus indica seed ash (WETSA) has been proven as a reaction media for one-pot three-component reaction between C−H activated carbonyl compound, aryl aldehyde, and malononitrile which acts as a basic catalyst. This novel method offers several advantages such as simple work-up, excellent yield, short reaction time, green reaction conditions, and the reaction even proceeds smoothly without any external promoter. The catalyst was recycled up to four times without significant loss in catalytic activity.

Visualizing peroxynitrite fluxes and protective effect of endogenous hydrogen sulfide during carbonyl stress in endothelial cell

Carbonyl stress is caused by active carbonyl compounds. Abnormal metabolism will produce high concentration of active carbonyl substances, leading to carbonyl stress, thus inducing cell damage or apoptosis. It is important to find effective markers for carbonyl stress level and find therapeutic or palliative drugs. Peroxynitrite (ONOO−), as a kind of important reactive oxygen species, can be produced under a variety of pathological conditions. Hydrogen sulfide (H2S) has been known as antioxidant agent, anti-inflammatory et al. However, the protective effect of H2S and the level of ONOO− in endothelial cell apoptosis during carbonyl stress kept unknown. Herein, for address it, we reported the first single-molecule fluorescent probe (SZ) is capable of detecting ONOO− and H2S in Endothelial cell. The probe SZ shows good selectivity and low detection limit to ONOO− and H2S. More importantly, probe SZ may be a useful tool for evaluating and confirming the protective effects of endogenous H2S in Endothelial cell during carbonyl stress.

Molecular stress and chronic metabolic disorders

Stress is the response of the organism to various external and internal events. All response reactions change from metabolic processes to metabolic stresses in minutes or even seconds. The scientists most often discuss oxidative, nitrosative and carbonyl stresses which are characterized by the accumulation of free radicals and other reactive oxygen species, as well as active carbonyl compounds, in the cells and extracellular fluid. These active (signal) molecules are powerful nonspecific modifiers of the structure and function of proteins, lipids, carbohydrates, and they interfere with bioenergetics. Small doses of active signal molecules are necessary for adaptive reactions of the body, they inhibit metabolic disorders, especially protein disorders, but their excessive accumulation causes pathological processes with pronounced modification of proteins and cardiovascular, neurodegenerative, autoimmune, connective tissue diseases and cancer. The authors discuss possible protection and prevention measures of metabolic stress.

Umpolung Strategy for the Synthesis of Chiral Dispiro[2-amino-4,5-dihydrofuran-3-carbonitrile]bisoxindoles

Based on a novel umpolung strategy, an efficient and highly enantioselective cascade aldol/cyclization/tautomerization of the 2-(2-oxoindolin-3-yl)malononitrile to active carbonyl compounds with excellent diastereo- and enantioselectivity has been developed. Also, various enantio-enriched multifunctional dispiro[2-amino-4,5-dihydrofuran-3-carbonitrile]bisoxindoles with adjacent spiro-stereocenters were conveniently obtained by this novel methodology. Also, the dispiro[2-amino-4,5-dihydrofuran-3-carbonitrile]bisoxindoles were easily transformed into structurally complex molecules without any effect on the diastereo- and enantioselectivity.

SUN-668 Elevated Osmolal Gap in Long-Term Complication of Type 2 Diabetes

Osmolal gap (OG) is the difference between the measured osmolality and calculated osmolality estimated by using the mathematical equation. Elevated OG indicates the presence of osmotically active particles undetected in the plasma of healthy individuals. Elevated OG has been observed in multiorgan trauma as a useful prognostic factor of patient survival [1, 2]. We hypothesized that elevated OG may occur in patients with type 2 diabetes (T2D) and may become a useful indicator of unmeasured endotoxins. One of the major mechanisms of this phenomenon may be non-enzymatic glycation of proteins in hyperglycemia, in which the osmotic active carbonyl compounds such as glyoxal, methylglyoxal, and 3-deoxyglucosone, are formed. Testing was performed for participants with T2D, aged 18 to 85. The osmolality measurement was performed with venous blood using the osmometer. The concentration of individual osmols (sodium, potassium, glucose, urea) was determined and on this basis, osmolality was calculated using the Dorwart-Chalmers formula: osmolality (mOsm/kg H2O) = 1.86 x [Na+] + glucose + urea + 9 (Dorwart, 1975). The clinical profile of patients was established based on history and physical examination (age, sex, age, duration of T2D, complications of T2D, HbA1c, LDL-cholesterol, triglyceride, BMI, coexisting diseases, medication). Data were analyzed using descriptive statistics. This study is currently ongoing, but preliminary data from the pilot study suggest an increased mean measured osmolality as well as elevated OG in patients with T2D compared to the reference values for healthy adults. These values differed depending on the type of long-term complications and the duration of the disease. In the pilot study, the highest OG was reported in diabetic retinopathy. A follow-up study with a larger sample may have a better ability to detect the statistical significance of the association of OG and complications of T2D. The association of the osmolal gap and complication of type 2 diabetes is poorly understood, and further investigation is warranted.

Pitfalls in the 3, 5-dinitrosalicylic acid (DNS) assay for the reducing sugars: Interference of furfural and 5-hydroxymethylfurfural

Transformation of renewable biomass into value-added chemicals and biofuels has evolved to be a vital field of research in recent years. Accurate estimation of reducing sugars post pretreatment of lignocellulosic biomass has been very inconsistent. For a few decades, 3,5-dinitrosalicylic acid (DNS) assay has been widely employed for the estimation of reducing sugars derived from pretreatment of lignocellulosic biomass. This assay tests for the presence of free carbonyl group (C=O), the so-called reducing sugars. This involves the oxidation of the aldehyde functional group present to the corresponding acid while DNS is simultaneously reduced to 3-amino-5-nitrosalicylic acid under alkaline conditions. However, the presence of other active carbonyl groups can potentially also react with DNS leading to incorrect yields of reducing sugars. Therefore, a detailed study has been carried out to evaluate the influence of active carbonyl compounds like furfural and 5-hydroxymethylfurfural (5-HMF) in the overall estimation of reducing sugars (glucose, xylose and arabinose) by DNS assay. In addition to this, reducing sugars estimation in the presence of furans were also investigated, it reveals that reducing sugars estimation was found to be 68% higher than actual sugars. Therefore, current findings strongly indicate that the employment of DNS assay for quantifying the reducing sugars in the presence of furans is not appropriate.

Palladium Nanoparticles Catalyzed Alkylation of 2-Alkylazaarenes with Activated Carbonyl Compounds

Key words palladium catalysis - nanoparticles - alkylation - keto amides - alkylazaarenes - C–H functionalization

Ligand‐Free and Reusable Palladium Nanoparticles‐Catalyzed Alkylation of 2‐Alkylazaarenes with Activated Ketones under Neutral Conditions

AbstractA mild, efficient, and stable binaphthyl‐stabilized palladium nanoparticles (Pd−BNP) catalyzed (sp3)C−H reaction of 2‐alkylazaarenes with activated carbonyl compounds was developed. Various activated carbonyl compounds such as α‐keto amide, isatin, 1,2‐diketone, α‐keto ester, trifluoromethyl ketone, and phenylglyoxal derivatives were examined and most of the compounds underwent the reaction smoothly to provide the corresponding products in moderate to excellent yields. Moreover, chemoselective reactions of α‐keto amides in the presence of simple ketones were achieved. Also, the model reaction was extended to a gram‐scale synthesis and some of the products were utilized for derivatization to form the corresponding N‐oxides, acryl amides and 1,2‐diol, respectively. The major advantages of the protocol are neutral reaction conditions, no additional requirement of external ligand, and successful reusability of the Pd−BNP catalyst up to five cycles without losing its activity and yield. Hg‐poisoning and hot filtration tests confirmed the heterogeneity of the Pd−BNP catalyst.magnified image

Catalyst‐Free One‐Pot Regioselective Synthesis of Spiropyrrolizines Using 1,3‐Dipolar Cycloaddition Reaction

AbstractSynthesis of functionalized spiro[acenaphthylene‐1,3′‐pyrrolizin]‐2‐ones and spiroindeno[1,2‐b]quinoxaline‐11,3′‐pyrrolizines has been reported by one‐pot condensation of active carbonyl compounds, L‐proline/L‐thioproline and 3‐methyl‐4‐nitro‐5‐styrylisoxazoles in MeOH under reflux. This multicomponent strategy afforded corresponding spiro products in 94–98% yield with high diastereo‐ and regioselectivity. The structure has been further confirmed by X‐ray analysis of single crystal of one of the compounds. The striking feature of this work is avoidance of usage of toxic catalysts for this one‐pot synthesis.