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A simple, straightforward, and highly efficient multicomponent one-pot synthesis of a series of pharmaceutically interesting functionalized chromeno[3′,4′:5,6]pyrano[2,3-d]pyrimidines has been developed based on a low-cost and environmentally benign trisodium citrate dihydrate catalyst via ultrasound-assisted tandem reactions of 4-hydroxycoumarin, aromatic aldehydes, and barbituric acid/thiobarbituric acid in aqueous ethanol at ambient conditions. Metal-free synthesis, high atom-economy, good to excellent yields, short reaction time, operational simplicity, eco-friendliness, and mild reaction conditions are some of the important features of his protocol.

In recent years, deep eutectic solvents have become attractive due to their interesting characteristics such as, physicochemical properties, low cost of components, easiness to prepare, low toxicity, bio-renewability, and biodegradability. In order to make the deep eutectic mixture more cost-effective and renewable, carbohydrate derivatives were linked with deep eutectic mixtures, since, carbohydrates are the most important and widespread renewable compounds on the earth. In this work, we have used low melting mixtures comprised of carbohydrates to create the reaction media for organic transformations. The physical properties such as density, viscosity, acidity, refractive index, surface tension, solubility, glass transition temperature, thermal stability, solvent polarity, and toxicity of the mixture were studied. Low melting mixtures were used as reaction media and catalysts for the effective synthesis of Barbiturates. The reaction between aldehydes and barbituric acid/thiobarbituric acid, and the reaction between aldehydes, barbituric acid/thiobarbituric acid, and malononitrile/dimedone were performed effectively with good to excellent yields. The recyclability of the catalyst/solvent was also established.

A 2,2′-Bipyridine-based ionic compound named 2,2′-bipyridinium dihydrogen phosphate was synthesized by addition of phosphoric acid to a solution of 2,2′-Bipyridine in dichloromethane. After the characterization using FT-IR, mass, 1H, 13C and 31P NMR techniques, it was used as a Bronsted dicationic acidic catalyst for the promotion of the synthesis of 2-arylidene malononitrile and 5-arylidene barbituric acid derivatives via Knoevenagel condensation reaction in water. Some of the advantages of this method are the utilization of an easy preparable, cost-effective and eco-friendly organic salt as a catalyst within high rates and yields of the reactions, simple and quick work-up and acceptable reusability of the catalyst.

Electronic interactions in donor-π-linker-acceptor systems with barbituric acid as an electron acceptor and possible electron donor were investigated to screen promising candidates with a push–pull character based on experimental and quantum chemical studies. The tautomeric properties of 5-benzylidenebarbituric acid derivatives were studied with NMR spectra, spectrophotometric determination of the pKa values, and quantum chemical calculations. Linear solvation energy relationships (LSER) and linear free energy relationships (LFER) were applied to the spectral data - UV frequencies and 13C NMR chemical shifts. The experimental studies of the nature of the ground and excited state of investigated compounds were successfully interpreted using a computational chemistry approach including ab initio MP2 geometry optimization and time-dependent DFT calculations of excited states. Quantification of the push–pull character of barbituric acid derivatives was performed by the 13CNMR chemical shift differences, Mayer π bond order analysis, hole-electron distribution analysis, and calculations of intramolecular charge transfer (ICT) indices. The results obtained show, that when coupled with a strong electron-donor, barbituric acid can act as the electron-acceptor in push–pull systems, and when coupled with a strong electron-acceptor, barbituric acid can act as the weak electron-donor.

Hepatic stellate cells (HSCs) are the major profibrogenic cells that promote the pathogenesis of liver fibrosis. The crosstalk between transforming growth factor-β1 (TGF-β1) signaling and lipopolysaccharide (LPS)-induced NF-κB signaling plays a critical role in accelerating liver fibrogenesis. Until now, there have been no FDA-approved drug treatments for liver fibrosis. Barbituric acid derivatives have been used as antiasthmatic drugs in the clinic; however, the effect of barbituric acid derivatives in treating liver fibrosis remains unknown. In this study, we synthesized a series of six barbituric acid (BA) derivatives, and one of the compounds, BA-5, exhibited the best ability to ameliorate TGF-β1-induced HSC activation without overt cytotoxic effects. Then, we treated HSCs and RAW264.7 macrophages with BA-5 to analyze the cross-talk of anti-fibrotic and anti-inflammatory effects. Carbon tetrachloride (CCl4)-induced liver fibrosis mouse model was used to evaluate the therapeutic effects of BA-5. Treatment with BA-5 inhibited TGF-β1-induced α-SMA, collagen1a2, and phosphorylated smad2/3 expression in HSCs. Furthermore, BA-5 treatment reversed the LPS-induced reduction in BAMBI protein and decreased IκBα and NF-κB phosphorylation in HSCs. NF-κB nuclear translocation, MCP-1 secretion, and ICAM-1 expression were also inhibited in BA-5-treated HSCs. Conditioned medium collected from BA-5-treated HSCs showed a reduced ability to activate RAW264.7 macrophages by inhibiting the MAPK pathway. In the mouse model, BA-5 administration reduced CCl4-induced liver damage, liver fibrosis, and F4/80 expression without any adverse effects. In conclusion, our study showed that the barbituric acid derivative BA-5 inhibits HSCs activation and liver fibrosis by blocking both the TGF-β1 and LPS-induced NF-κB signaling pathways and further inhibits macrophages recruitment and activation.

The present invention relates to the use of barbituric acid derivatives of the formula I as self-tanning substance, for increasing melanin synthesis, for improving melanin transport and/or improving the distribution of melanin in superbasal layers, to preparations comprising these barbituric acid derivatives, and to specific barbituric acid derivatives.

Verjuice (unripe grape juice), a natural mixture of organic acids, which is identified by pH-metric and TGA analysis, is efficiently used for the promotion of the synthesis of 5-arylmethylenepyrimidine-2,4,6-triones, via Knovenagel condensation reaction between barbituric or thiobarbituric acid and aldehydes. Verjuice is also employed for the effective synthesis of pyrano[2,3-d]pyrimidinone derivatives via a three-component reaction of barbituric acid or its thio analogue, aldehydes and malononitrile. In the same way, pyrimido[4,5-d]pyrimidinone derivatives are simply produced via the reaction of barbituric acid, aldehydes and urea or thiourea in the presence of verjuice. This green methodology rewards notable advantages including simple procedures, acceptable reaction times, easy work-up, high yields, circumventing the use of any expensive starting materials, volatile and hazardous organic solvents during the reaction and work-up process, and use of a natural, low-cost, reusable, and bio-degradable catalyst.

We report synthesis of triphenyl(propyl-3-hydrogen sulfate)phosphonium bromide ([TPPHSP]Br) as a reusable green Br?nsted-acidic ionic liquid catalyst and its application for synthesis of 5-arylidene barbituric acids and pyrano[2,3-d]pyrimidine derivatives by condensation reaction between aromatic aldehydes and barbituric acid or aromatic aldehydes, malononitrile, and barbituric acid in EtOH–H2O in reflux condition with good to excellent yield. The [TPPHSP]Br IL catalyst was characterized by Fourier-transform infrared (FT-IR) spectroscopy, 1H and 13C nuclear magnetic resonance (NMR), and thermogravimetric (TG) analysis and showed good catalytic activity and reusability.

In the present work, 3,3′-(butane-1,4-diyl)bis(1-methyl-1H-imidazol-3-ium) dichloride ([C4(MIm)2]·2Cl) and 3,3′-(butane-1,4-diyl)bis(1-methyl-1H-imidazol-3-ium) hydrogen sulfate ([C4(MIm)2]·2HSO4) were prepared via adequate, solvent-free methods and characterized using FT-IR, 1H NMR, 13C NMR, and potentiometric titration techniques. These reagents were investigated in the synthesis of 5-arylidene (thio)barbituric acids, 2-arylidene malononitriles, 4H-pyrans, and pyrano[2,3-d] pyrimidineones, and their catalytic activities were compared in the promotion of these reactions. Based on the obtained results, we found that [C4(MIm)2]·2Cl showed more catalytic efficiency where a basic or weak acidic media is needed. In contrast, [C4(MIm)2]·2HSO4 is a powerful catalyst in reactions needing acidic catalysts to enhance the reaction rate. Using these reagents, the products were formed under mild and eco-friendly conditions in excellent yields during short reaction times without needing column chromatography for work-up.

In this study, Co3O4 nanocatalysts were constructed in environmentally appropriate conditions using controlled, effective, and facile microwave method. The final nanostructures were characterized by SEM, XRD, and TEM analyses. The products had a small size distribution, homogeneous morphology, and crystallographic structures associated with the formation of Co3O4 nanostructures. Moreover, EDS mapping analysis confirmed the existence of Co and O elements in the final structure, and the magnetic properties of the samples were investigated by VSM. The application of this nanostructure in a catalytic process was further examined, and the results suggested that it could be used as a novel candidate for the synthesis of arylidene barbituric and Meldrum,s acid through Knoevenagel condensation of aldehydes by barbituric and Meldrum,s acid in aqueous media. The high yield of these nanocatalysts would be justified by the nature of the nanostructure as well as the experimental procedure developed in this study, which affected the physicochemical features of the products.

Butane-1-sulfonic acid immobilized on magnetic Fe3O4@SiO2 nanoparticles (Fe3O4@SiO2-Sultone) was easily prepared via direct ring opening of 1,4-butanesultone with nanomagnetic Fe3O4@SiO2. The prepared reagent was characterized and used for the efficient promotion of the synthesis of barbituric acid and pyrano[2,3-d] pyrimidine derivatives. All reactions were performed under mild and completely heterogeneous reaction conditions affording products in good to high yields. The catalyst is easily isolated from the reaction mixture by magnetic decantation and can be reused at least eight times without significant loss in activity.

A mild, simple and efficient procedure for the preparation of barbituric acid and pyrano[2,3-d]pyrimidine derivatives in aqueous media is described using 4-(4-propylpiperazine-1-yl)butane-1-sulfonic acid-modified silica-coated magnetic nanoparticles as a novel and reusable catalyst. The catalyst was easily isolated from the reaction mixture by magnetic decantation using an external magnet and reused at least eight times without significant degradation in activity.

Barbituric and thiobarbituric acid derivatives have become progressively attractive to medicinal chemists due to their wide range of biological activities. Herein, different series of 1,3,5-trisubstituted barbiturates and thiobarbiturates were prepared in moderate to excellent yields and their activity as xanthine oxidase inhibitors, antioxidants, antibacterial agents and as anti-proliferative compounds was evaluated in vitro. Interesting bioactive barbiturates were found namely, 1,3-dimethyl-5-[1-(2-phenylhydrazinyl)ethylidene]pyrimidine-2,4,6(1H,3H,5H)-trione (6c) and 1,3-dimethyl-5-[1-[2-(4-nitrophenyl)hydrazinyl]ethylidene]pyrimidine-2,4,6(1H,3H,5H)-trione (6e), which showed concomitant xanthine oxidase inhibitory effect (IC50 values of 24.3 and 27.9 μM, respectively), and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity (IC50 values of 18.8 and 23.8 μM, respectively). In addition, 5-[1-(2-phenylhydrazinyl)ethylidene]pyrimidine-2,4,6(1H,3H,5H)-trione (6d) also revealed DPPH radical scavenger effect, with an IC50 value of 20.4 μM. Moreover, relevant cytotoxicity against MCF-7 cells (IC50 = 13.3 μM) was observed with 5-[[(2-chloro-4-nitrophenyl)amino]methylene]-2-thioxodihydropyrimidine-4,6(1H,5H)-dione (7d). Finally, different 5-hydrazinylethylidenepyrimidines revealed antibacterial activity against Acinetobacter baumannii (MIC values between 12.5 and 25.0 μM) which paves the way for developing new treatments for infections caused by this Gram-negative coccobacillus bacterium, known to be an opportunistic pathogen in humans with high relevance in multidrug-resistant nosocomial infections. The most promising bioactive barbiturates were studied in silico with emphasis on compliance with the Lipinski's rule of five as well as several pharmacokinetics and toxicity parameters.

In this article, the preparation of bis-imidazolium hydrogen sulfate and bis-imidazolium perchlorate as two new bis-dicationic Br?nsted acidic ionic liquids based on imidazole is reported. After characterization by FT-IR, mass and NMR spectroscopy and pH titration, the applicability of these reagents is studied in the promotion of the synthesis of 5-arylidene barbituric acids and pyrano[2,3-d] pyrimidinone derivatives. These methods possess some advantages such as ease of preparation of the catalyst, simple work-up procedure, short reaction times, excellent yields, and use of nonorganic solvents during all steps of the reactions and good reusability of the catalysts.

The reactivity and chemo-, regio- and diastreo-selectivity of tosylmethyl isocyanides (TosMIC) are investigated in Van Leusen type [3 + 2] cycloaddition reactions with the various activate cyclic ketones and double C–C bonds in the synthesis of spirooxazolines, spiropyrrolines and chromeno[3,4-c]pyrrols in good to excellent yields under catalyst-free conditions without any activation at ambient temperature.

A metal- and catalyst-free reductive alkylation protocol for the one-pot synthesis of 5-monoalkylbarbiturates from barbituric acids and aldehydes using the in situ generated chemoselective reducing agent 2-phenyl-2,3-dihydrobenzo[ d ]thiazole from 2-aminothiophenol and benzaldehyde is described. The notable advantages of the protocol are operational simplicity, mild reaction conditions, high yield, short reaction time, and simple workup and purification process which make it highly attractive.

Background: Benzimidazole and benzothiazole subunits exist in many biologically active molecules, natural products, and synthetic compounds. These compounds have recently gained widespread interest due to their key role in medically important compounds, such as those exhibiting anticancer activity, antimicrobial activity, inhibition of hepatitis C virus NS5B polymerase, p38 kinase inhibitory activity, and anti-inflammatory activity. Methods: 2-Substituted benzimidazole and benzothiazole derivatives have been synthesized by the condensation of 1,2-phenylenediamine or 2-aminobenzothiophenol with 5-arylidenepyrimidine-2,4,6-(1H,3H, 5H)-trione derivatives via cleavage of C-C double bond without using a catalyst in EtOH under reflux conditions. Results: We report here a very simple, novel, efficient, and catalyst-free method for the synthesis of benzimidazole and benzothiazole in good to excellent yields from the treatment of 1,2-phenylenediamine and 2-aminothiophenol with various 5-arylidenepyrimidine-2,4,6(1H,3H,5H)-trione, respectively. This reaction proceeds via cleavage of a C=C double bond and elimination of barbituric acid. Conclusion: This method appears to be general for the synthesis of benzimidazoles and benzothiazoles using 5-arylidenepyrimidine-2,4,6-(1H,3H,5H)-trione derivatives containing various aromatic and heteroaromatic aldehydes such as furfural and thiophene-2-carbaldehyde with electron-withdrawing and electron-releasing groups.

The present invention relates to novel barbiturate and thiobarbiturate derivatives and a composition for promoting hair growth using the same. According to the present invention, the barbiturate and thiobarbiturate derivatives, in an animal model, have shown to promote hair growth and have excellent effects on hair growth by promoting regulation of Wnt/andbeta;-catenin and hair growth factor signaling and suppressing mechanism of apoptosis. Accordingly, the barbiturate and thiobarbiturate derivatives of the present invention may be used as a composition for promoting hair growth.COPYRIGHT KIPO 2017

In this work, succinimidinium hydrogensulfate ([H-Suc]HSO4), a newly reported Br?nsted acidic ionic liquids is used as an efficient, homogeneous and reusable catalyst for the synthesis of 5-arylidenepyrimidine-2,4,6(1H,3H,5H)-trione and pyrano[2,3-d]-pyrimidine dione derivatives. The products were formed in excellent yields over short reaction times and the catalyst can be reused several times without any appreciable loss in its activity.

A new and straightforward method for the synthesis of 5-arylidine barbituric and thiobarbituric acids through a reaction between barbituric acid and its thio-analogue with aldehydes using 1,4-disulfo-1,4-diazabicyclo[2.2.2]octane-1,4-diium dihydrogen sulfate ([DABCO](SO3H)2(HSO4)2) as an efficient catalyst has been reported. In this project, also the preparation of pyrano[2,3-d]-pyrimidinediones via the reaction of barbituric or thiobarbituric acid, malononitrile and aldehydes in the presence of this reagent and 1,4-disulfo-1,4-diazabicyclo[2.2.2]octane-1,4-diium chloride ([DABCO](SO3H)2(Cl)2) has been investigated. The structure of the products was characterized using IR, 1H NMR and 13C NMR spectroscopy. The present methodologies suggests several advantages such as ease of the preparation and handling of the catalysts, high yields, simple and green procedures, low cost, short reaction times, easy work-up and preformation of the reaction in water as a green solvent.

PURPOSE: A novel compound with skin whitening, antioxidation, and PPAR activation effects, and a medical use thereof are provided to be used for a pharmaceutical composition or a cosmetic product. CONSTITUTION: A compound is denoted by chemical formula 1. A skin whitening composition contains the compound as an active ingredient. An antioxidative composition for preventing or treating oxidative diseases contains the compound of chemical formula 1 as an active ingredient. The oxidative diseases are selected among skin aging, pigmentation, wrinkling, psoriasis, or eczema. The composition prevents or treats diseases which are regulated by PPAR(peroxisome proliferator-activated receptor) activity. The PPAR includes PPAR alpha or PPAR gamma.

A series of 5-(arylmethylene)hexahydropyrimidine-2,4,6-triones were synthesized. Their antimycobacterial activity and acute daily toxicity with respect to M. lufu were investigated.

Succinimidinium N-sulfonic acid hydrogen sulfate ([SuSA-H]HSO4) as a new ionic liquid is prepared and characterized using a variety of techniques, including infrared spectra (FT-IR), 1H and 13C NMR, scanning electron microscopy, a mass spectra method, as well as by Hammett acidity function. The prepared reagent is efficiently able to catalyze the preparation of 5-arylmethylene-pyrimidine-2,4,6-triones via the condensation of aldehydes and barbituric acid. Further studies showed that the condensation of aldehydes with barbituric acid and malononitrile leading to pyrano[2,3-d]pyrimidinone derivatives can also be efficiently promoted in the presence of this reagent. The present methodology offers several advantages, including ease of the preparation and handling of the catalyst, simple and easy work-up, short reaction times, high yields of the products and recyclability of the catalyst.

1,8-Dioxo-octahydro-xanthenes are easily prepared via the condensation of aldehydes with 1,3-cyclohexadione and/or dimedone using N-sulfonated DABCO as a new and efficient catalyst. This reagent is also efficiently able to catalyze the condensation of aldehydes with barbituric acid leading to 5-arylmethylene-pyrimidine-2,4,6-triones. The structure of the products was characterized by their IR, 1H NMR, and 13C NMR spectroscopy. The present methodology offers several advantages such as ease of preparation and handling of the catalyst, high yields, simple and green procedure, low cost, short reaction times, easy work-up, and preformation of the reaction in the absence of solvent or in water as a green solvent.

A group of novel 4-bromo-7,9-dimethyl-1-aryl-2-oxa-3,7,9-triaza-spiro[4.5]dec-3-ene-6,8,10-trione derivatives is prepared through 1,3-dipolar cycloadditions between benzylidenes and bromonitrile oxide. This reaction is shown to have high atom economy.

This work describes the design, synthesis and in vivo evaluation of new central nervous system depressing agents that show low levels of acute toxicity as well as high solubility in water and exhibit anxiolytic and hypnotic effects. These new compounds are sodium 2-benzyl-2-chloromalonates, which were designed using molecular modelling techniques and synthesized in four steps, with an overall yield between 41% and 65%. In vivo tests with mice, including pentobarbital-induced sleep, rotarod, open field and elevated plus maze tests, were carried out, and the results indicated that some of these agents induce activities similar to those induced by diazepam but with lower hypnotic potency and greater anxiolytic potency. These compounds were also orally administered to mice in doses of 2 g kg-1, and their effects were evaluated for 14 days. The mice did not show signs of intoxication, confirming that sodium 2-benzyl-2-chloromalonates exhibit low levels of acute toxicity. These observations indicate that sodium 2-benzyl-2-chloromalonates and their analogues are efficient and safer central nervous system depressing drugs relative to existing standards of care.

The present invention relates to methods of inhibiting shikimate pathway, comprising administering to a subject a pharmaceutically acceptable composition comprising a compound having a formula: or pharmaceutically acceptable salts thereof. The present invention also provides a synergistic antibacterial composition containing compound

5-Alkyl/arylidenebarbituric acids were efficiently synthesized through an FeCl3·6H2O catalyzed domino reaction of 6-aminouracils, water and aldehydes with water serving a dual role as both solvent and reactant, under benign reaction conditions. A study on comparative substrate scope of 6-aminouracil versus barbituric acid showed similar efficacy towards 5-alkyl/arylidenebarbituric acids. The protocol is the first detailed report to prepare regioselectively 5-alkyl/arylidenebarbituric acids starting from 6-aminouracils, which is an alternative and competing strategy to hitherto all known reactions directly employing barbituric acids. the Partner Organisations 2014.

Provided are a novel compound having skin-whitening, anti-oxidizing and PPAR activities and a medical use thereof, and the compound has skin-whitening activities for the suppression of tyrosinase, and accordingly, is useful for use in skin-whitening pharmaceutical composition or cosmetic products; has anti-oxidant activities, and accordingly, is useful for the prevention and treatment of skin-aging; and has PPAR activities, and in particular, PPARα and PPARγ activities, and accordingly, is useful for use in pharmaceutical compositions or health foods which are effective for the prevention and treatment of obesity, metabolic disease, or cardiovascular disease.

Here a new class of hydroxy- or methoxy-substituted 5-benzylidene(thio) barbiturates were designed, synthesized and their inhibitory effects on the diphenolase activity of mushroom tyrosinase were evaluated. The results showed that several compounds had more potent tyrosinase inhibitory activities than the widely used tyrosinase inhibitor kojic acid (IC50 = 18.25 μM). In particular, 3′,4′-dihydroxylated 1e was found to be the most potent inhibitor with IC50 value of 1.52 μM. The inhibition mechanism analysis revealed that the potential compounds 1e and 2e exhibited such inhibitory effects on tyrosinase by acting as the irreversible inhibitors. Structure-activity relationships' (SARs) analysis also suggested that further development of such compounds might be of interest.

Reaction of 5-arylidene barbiturates (3a-i) with hydrazine hydrate resulted in the unusual formation of novel benzalazines (5a-i) in 70-90% yield rather than the expected pyrazole fused pyrimidines.

Benzylidene barbiturates are important materials for the synthesis of heterocyclic compounds with potential for the development of new drugs. The reactivity of benzylidene barbiturates is mainly controlled by their exocyclic carbon-carbon double bond. In this work, the exocyclic double bond polarization was estimated experimentally by NMR and correlated with the Hammett σ values of the aromatic ring substituents and the molecular modeling calculated atomic charge difference. It is demonstrated that carbon chemical shift differences and NBO charge differences can be used to predict their reactivity.

A coprecipitation method was used to synthesize superparamagnetic CoFe 2O4 nanoparticles without using any capping agents/surfactants. The prepared nanoparticles were characterized using Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, X-ray diffraction, a vibrating sample magnetometer (VSM), N2 adsorption and thermogravimetric/differential thermal analysis/differential thermal gravimetry techniques. The synthesized spinel CoFe2O4 nanoparticles had an average size of 2-8 nm with a high surface area (140.9 m2/g). The field-dependent magnetization, demonstrated by VSM and saturation magnetization, was found to be 1.77 emu/g. An efficient method was used for the synthesis of arylidene barbituric acid derivatives using CoFe2O4 magnetic nanoparticles as a magnetically separable and reusable catalyst in aqueous ethanol. The attractive features of this synthetic protocol were very short reaction time, high yields, high turnover frequency, simple work-up procedure, economy, a clean reaction methodology, and chemoselectivity, as well as provision of an ecofriendly and green synthesis.

The reversibly formed C?￡N bond plays a very important role in dynamic covalent chemistry and the C?￡N/C?￡N exchange of components between different imine constituents to create dynamic covalent libraries has been extensively used. To facilitate diversity generation, we have investigated an organocatalyzed approach, using L-proline as catalyst, to accelerate the formation of dynamic libraries of [n×n] imine components. The organocatalysis methodology has also been extended, under somewhat modified conditions, to reversible C?￡C/C?￡N exchange processes between Knoevenagel derivatives of barbituric acid and imines, allowing for the generation of increased diversity. Copyright

Knoevenagel condensation of barbituric acids with aromatic aldehydes containing one or two formyl groups was carried out. 5-Arylidenebarbituric acids underwent smooth hetero-Diels-Alder (HDA) reactions with enol ethers to afford cis and trans diastereoisomers of pyr-ano[2,3-d]pyrimidine-2,4-diones and 5,5′-(1,4-phenylene)-bis[2H-pyrano[2,3-d]pyrimidine-2,4(3H)-dione] derivatives in excellent yields (75-88%). Syntheses were realized by Knoevenagel condensation and HDA reaction in four different reaction conditions: Knoevenagel condensation in water and Diels-Alder reaction in methylene chloride solution, Knoevenagel condensation in water and Diels-Alder reaction without solvent, three-component one-pot reaction in methylene chloride solution, or three-component one-pot reaction in water. All reactions were carried out without catalyst at room temperature. The reactions of malononitrile with Knoevenagel condensation products of barbituric acids and heteroaromatic aldehydes or terephthalaldehyde were examined and did not provide corresponding pyranopyrimidines.

A new family of barbiturates, 5-chloro-5-benzylbarbituric acids, was prepared using a simple efficient synthetic method from aromatic aldehydes and barbituric acid, followed by reduction and chlorination with trichloro-isocyanuric acid, affording overall yields of 53 to 70percent. The in vivo evaluation with mice showed that these compounds present tranquilizing activity.

A systematic study of Knoevenagel reaction and Nazarov cyclization was made on variety of less reactive carbonyl compounds such as β-ketoesters, 1,3-diketones and cyclic active methylene compounds using Yb(OTf)3 as the catalyst. Recycling study confirms reusability of the catalyst without much loss of activity.

An efficient method for Knoevenagel condensation of arenecarbaldehydes with active methylene compounds such as barbituric acid and Meldrum's acid in the presence of gel-entrapped base catalysts is reported. The method has been extended to the one-pot synthesis of arylmethylene-bis[3-hydroxycyclohex-2-en-1- one] derivatives from dimedone (=5,5-dimethylcyclohexane-1,3-dione) and arenecarbaldehydes by using domino Knoevenagel/Michael reaction sequence. Copyright

Resistance to commercially available antimicrobials is increasing at alarming rate therefore there is an urgent need of new antimicrobial compounds and materials with novel modes of action to tackle the problem of resistance in pathogenic gram positive and gram negative bacteria. The current study involves the design and synthesis of new molecular structures which should not resemble the basic molecular structures of the existing classes of antimicrobial agents in order to avoid the risks of cross resistance development. A total of 14 metal-barbiturate complexes (newly synthesized compounds) were evaluated for their antimicrobial properties against multiple drug resistance clinical isolates of S. aureus and E. coli. Broth dilution method was used to determine minimum inhibitory and bactericidal activity of the newly synthesized compounds. The results showed that the metal-barbiturate complexes with cobalt ions were more effective against E. coli and S. aureus as compared to other compounds. Moreover the activity of these compounds was higher against S. aureus as compared to E. coli which indicates species specific variable antimicrobial effects of these compounds.

A straightforward and efficient method for the synthesis of nitriles or β-cyanocarbonyls via Knoevenagel condensation and Michael addition reaction of a barbituric acid, aldehyde and sodium cyanide in water without using any catalyst or activation at 70 °C is reported. The Royal Society of Chemistry.

Reaction of barbituric acid (BA), 1,3-dimethyl barbituric acid (DMBA) and 2-thiobarbituric acid (TBA) with cyanogen bromide and aldehydes in the presence of L-(+)-tartaric acid afforded a new route for the synthesis of stable heterocyclic 5-aryl-1H,1′H-spiro[furo[2,3-d]pyrimidine-6,5′- pyrimidine]2,2′,4,4′,6′(3H,3′H,5H)- pentaones which is a dimeric form of barbiturate (uracil and thiouracil derivative). In the reaction of 1,3-diethyl thiobarbituric acid (DETBA) the Knoevenagel condensation and then Michael adducts were obtained under the same condition. Structure elucidation is carried out by 1H NMR, 13C NMR, FT-IR and Mass analyses. Mechanism of the formation is discussed.

A large amount of evidence suggests that monocytes/macrophages infiltration is implicated in a variety of inflammatory diseases including acute liver injury. Monocyte chemoattractant protein 1 (MCP-1) plays a crucial role in the process of macrophages recruitment. We herein presented a small-molecule library and a feasible quick screening method of evaluating potency of inhibition of chemotaxis of RAW264.7 cells stimulated by MCP-1. Fifty-three small molecules were synthesized and screened, and four compounds (2g, 2h, 4f, and 6h) showed inhibitory effects with IC50 values range from 0.72 to 20.47 μM, with compound 4f being the most efficient. Further in vivo studies demonstrated that oral administration of 2g, 2h, 4f, or 6h decreases, most significantly for 4f, the serum levels of alanine aminotransaminase (ALT) and asparate aminotransaminase (AST) in ConA-induced acute livery injury BALB/c mice. Histopathological evaluation liver sections confirmed 4f as a potent, orally active compound for hepatoprotective effects against ConA-induced acute liver injury in BALB/c mice.

A series of Ce1MgxZr1-xo2 (CMZO) mixed metal oxide with different molar ratio were prepared by simple co-precipitation method. The prepared materials were tested for their catalytic activity performance using Knoevenagel condensation of various aromatic aldehydes with barbituric acid under solvent-free condition in microwave. The best catalytic activity was obtained with CMZO (1:0.6:0.4). The synthesized materials were characterized by using XRD, FT-IR, SEM-EDS techniques.

5-Benzylpyrimidin-2,4,6-triones (3a-c), 5-((furan-2-yl)methyl)pyrimidin-2, 4,6-trione (3g) and 5-((3-aryl-1-phe-nyl-1H-pyrazol-4-yl)methyl)pyrimidin-2,4,6- triones (3h-j) were obtained in two steps. Reaction of barbituric acid (1) with various substituted aromatic aldehydes, furfuraldehyde and 3-aryl-1-phenyl-1H- pyrazole-4-carbaldehydes in methanol yielded the corresponding chalcones 2a-m in 48-85% yield. These chalcones on reduction with sodium borohydride in isopropyl alcohol furnished desired novel compounds 3a-c and 3g-j in 55-85% yield. The structure of all the synthesized compounds have been established by various spectral studies and elemental analysis. All the synthesized compounds have been screened for antimicrobial activity.

The condensation of aromatic aldehydes and barbituric acid catalyzed by SiO212WO324H2O in aqueous media at room temperature gave 5-arylidene barbituric acid in high yields with or without the use of ultrasound, providing a simple and efficient route to synthesis of these compounds.

The syntheses of a new class of barbiturate-based inhibitors for human and Escherichia Coli methionine aminopeptidase-1 (MetAP-1) are described. Some of the synthesized inhibitors show selective inhibition of the human enzyme with high potency.

Several benzaldehydes were condensed with barbituric acid under microwave irradiation in absence of solvent affording the corresponding 5-arylidine barbituric acid derivatives in short reaction period with high yields.

Previously unknown 12-aryl-7,8,9,10,11,12-hexahydrobenzo[f]pyrimido[4,5-b] quinoline-9,11-diones were synthesized by three-component condensation of naphthalen-2-amine with substituted benzaldehydes and barbituric acid through intermediate 5-benzylidenebarbituric acids. Nauka/Interperiodica 2007.

Aminosulfonic acid is an environmentally friendly catalyst. Grinding a mixture of aromatic aldehydes, barbituric acid, and H2NSO 3H at room temperature (without any solvent) gave 5-arylidene barbituric acid in high yields, providing a simple and efficient route to synthesis of these compounds. Copyright Taylor & Francis Group, LLC.

The Knoevenagel condensation of aromatic aldehydes with active methylene compounds proceeded efficiently in a reusable ionic liquid, ethylammonium nitrate, at room temperature in the absence of any catalyst with high yields.