Showing papers on "Malonic acid published in 2011"
TL;DR: In this article, the authors defined the Knoevenagel condensation as the reaction between an aldehyde or ketone or any compound having an active methylene group, brought about by an organic base or ammonia and their salts.
Abstract: Knoevenagel's first papers in this field were concerned with the condensation of formaldehyde with diethyl malonate and with ethyl benzoylacetate. The catalyst was ethylamine. A number of other aldehydes were reported to condense similarly with diethyl malonate, ethyl benzoylacetate, ethyl benzoylpyruvate, and acetylacetone under the influence of various primary and secondary amines. In 1896, Knoevenagel reported benzaldehyde with ethyl aceoacetate condensed at room temperature in the presence of piperdine to give a bis compound, but that when the reaction was run in a freezing mixture, the product was acetoacetate. For the purposes of this chapter, the Knoevenagel condensation is defined as the reaction between an aldehyde or ketone or any compound having an active methylene group, brought about by an organic base or ammonia and their salts.
Keywords:
Knoevenagel condensations;
decarboxylation;
malonic acid;
active methylene component;
stereochemical aspects;
cyanoacetic acid;
ketones;
derivatives. caatalysts;
experimental conditions
125 citations
TL;DR: Highly enantioselective biomimetic Michael addition reactions of malonic acid half thioesters to a variety of nitroolefins, affording the optically active γ-amino acid precursors, were developed by employing the Cinchona-based squaramides.
Abstract: Highly enantioselective biomimetic Michael addition reactions of malonic acid half thioesters (MAHTs) to a variety of nitroolefins, affording the optically active γ-amino acid precursors, were developed by employing the Cinchona-based squaramides (up to >99% ee). Remarkably, this biomimetic process is enantioconvergent, a highly desirable feature of a catalytic asymmetric reaction, whereby E/Z-isomers of the nitroolefins afford the same product enantiomer. The synthetic utility of this organocatalytic protocol was also demonstrated in the formal synthesis of pharmaceutically important γ-amino acids such as baclofen. Moreover, a quantum chemical analysis of the catalyst-substrate complexes is shown to give a detailed and instrumental insight into the origin of the observed catalytic activity.
123 citations
TL;DR: The predictive topological polar surface area (TPSA) data allow concluding that they could have a good capacity for penetrating cell membranes, and one can propose these novel lipophilic compounds as potential antioxidants for tackling oxidative processes.
100 citations
TL;DR: A novel dinuclear cobalt(III) complex with the condensation product of 2-acetylpyridine and malonic acid dihydrazide, N',N'(2)-bis[(1E)-1-(2-pyridyl)ethylidene]propanedihydrazide was synthesized and characterized and showed a moderate activity towards Artemia salina.
94 citations
TL;DR: Cl cloning of a eukaryotic malonyl-CoA synthetase gene, Acyl Activating Enzyme13 (AAE13; At3g16170), from Arabidopsis thaliana is reported, demonstrating that the maloneyl- coA synthenase encoded by AAE13 is essential for healthy growth and development.
Abstract: Malonyl-CoA is the precursor for fatty acid synthesis and elongation. It is also one of the building blocks for the biosynthesis of some phytoalexins, flavonoids, and many malonylated compounds. In plants as well as in animals, malonyl-CoA is almost exclusively derived from acetyl-CoA by acetyl-CoA carboxylase (EC 6.4.1.2). However, previous studies have suggested that malonyl-CoA may also be made directly from malonic acid by malonyl-CoA synthetase (EC 6.2.1.14). Here, we report the cloning of a eukaryotic malonyl-CoA synthetase gene, Acyl Activating Enzyme13 (AAE13; At3g16170), from Arabidopsis thaliana. Recombinant AAE13 protein showed high activity against malonic acid (Km = 529.4 ± 98.5 μM; Vm = 24.0 ± 2.7 μmol/mg/min) but little or no activity against other dicarboxylic or fatty acids tested. Exogenous malonic acid was toxic to Arabidopsis seedlings and caused accumulation of malonic and succinic acids in the seedlings. aae13 null mutants also grew poorly and accumulated malonic and succinic acids. These defects were complemented by an AAE13 transgene or by a bacterial malonyl-CoA synthetase gene under control of the AAE13 promoter. Our results demonstrate that the malonyl-CoA synthetase encoded by AAE13 is essential for healthy growth and development, probably because it is required for the detoxification of malonate.
70 citations
TL;DR: The method provided procedural detection limits and robustness of the method was tested with soil extracts and samples from hydroponic experiments concerned the regulation of phosphorus solubilization via plant root exudation of citric, malic, and oxalic acid.
Abstract: A sensitive method for quantification of citric, fumaric, malic, malonic, oxalic, trans aconitic, and succinic acid in soil- and root-related samples is presented. The method is based on a novel, fast, and simple esterification procedure and subsequent analysis via liquid chromatography–mass spectrometry. Derivatization comprises in situ generation of HCl, which catalyzes the Fischer esterification with benzyl alcohol. As a key advance, the esterification with the aromate allows reversed-phase separation and improves electrospray ionization efficiency. The method provided procedural detection limits of 1 nM for citric, 47 nM for fumaric, 10 nM for malic, 10 nM for malonic, 16 nM for oxalic, 15 nM for succinic, and 2 nM for aconitic acid utilizing 500 μL of liquid sample. The working range was 3 nM to 10 μM for citric acid, 158 nM to 10 μM for fumaric acid, 34 nM to 10 μM for malic acid, 33 nM to 10 μM for malonic acid, 53 nM to 10 μM for oxalic acid, 48 nM to 10 μM for succinic acid, and 6 nM to 10 μM for aconitic acid. Quantification of the analytes in soil-related samples was performed via external calibration of the entire procedure utilizing 13C-labeled oxalic and citric acid as internal standards. The robustness of the method was tested with soil extracts and samples from hydroponic experiments. The latter concerned the regulation of phosphorus solubilization via plant root exudation of citric, malic, and oxalic acid.
69 citations
Patent•
19 Oct 2011
TL;DR: In this paper, a method of making a methylene malonate monomer that includes the steps of reacting a malonic acid ester with a source of formaldehyde was presented.
Abstract: The present invention provides a method of making a methylene malonate monomer that includes the steps of reacting a malonic acid ester with a source of formaldehyde optionally in the presence of an acidic or basic catalyst and optionally in the presence of an acidic or non-acidic solvent to form reaction complex. The reaction is optionally performed in the presence of or contacted with an energy transfer means such as a heat transfer agent, a heat transfer surface, a source of radiation or a laser such that reaction complex is substantially vaporized to produce a vapor phase comprising methylene malonate monomer which may be isolated. The present invention further provides methylene malonate monomers prepared by the method of the invention, as well as compositions and products formed from the methylene malonate monomers, including monomer-based products (e.g., inks, adhesives, coatings, sealants or reactive molding) and polymer-based products (e.g., fibers, films, sheets, medical polymers, composite polymers and surfactants).
66 citations
TL;DR: Malonic acid derivatives undergo unusually mild decarboxylation when treated with N,N'-carbonyldiimidazole (CDI) at room temperature to generate the carbonyl imidazoles moiety in high yield, which can be reacted further with a variety of nucleophiles in an efficient one-pot process.
59 citations
TL;DR: A new synthetic method for the preparation of cyclic malonic acid monoesters in aqueous media was developed based on the combination of a metathesis reaction and subsequent biocatalytic hydrolysis with a pig liver esterase in a one-pot synthesis.
Abstract: A new synthetic method for the preparation of cyclic malonic acid monoesters in aqueous media was developed based on the combination of a metathesis reaction and subsequent biocatalytic hydrolysis with a pig liver esterase in a one-pot synthesis. Both reaction steps proceed smoothly under optimized conditions in aqueous media requiring only a low amount of the metal catalyst for the metathesis reaction. Notably, the applied biocatalyst turned out to be highly compatible with the metal catalyst showing no significant influence on the enzyme activity.
57 citations
TL;DR: The results suggest that in deliquesced micrometer-size particles, carboxylic acids may exist in predominantly enol forms that need to be explicitly considered in atmospheric aerosol chemistry.
Abstract: Scanning transmission X-ray microscopy combined with near-edge X-ray absorption fine structure spectroscopy (STXM/NEXAFS) and optical microscopy coupled with Fourier transform infrared spectroscopy (micro-FTIR) have been applied to observe hygroscopic growth and chemical changes in malonic acid particles deposited on substrates. The extent of the hygroscopic growth of particles has been quantified in terms of the corresponding water-to-solute ratios (WSR) based on STXM/NEXAFS and micro-FTIR data sets. WSR values derived separately from two applied methods displayed a remarkable agreement with previous data reported in the literature. Comparison of NEXAFS and FTIR spectra acquired at different relative humidity (RH) shows efficient keto-enol tautomerization of malonic acid, with the enol form dominating at higher RH. The keto-enol equilibrium constants were calculated using relevant peak intensities in the carbon and oxygen K-edge NEXAFS spectra as a function of RH. We report strong dependence of the equilibrium constant on RH, with measured values of 0.18 ± 0.03, 1.11 ± 0.14, and 2.33 ± 0.37 corresponding to 2, 50, and 90% RH, respectively. Enols are important intermediates in aldol condensation reactions pertaining to formation and atmospheric aging of secondary organic aerosol (SOA). The present knowledge assumes that constituents of atmospheric deliquesced particles undergo aqueous chemistry with kinetic and equilibrium constants analogous to reactions in bulk solutions, which would estimate absolute dominance of the keto form of carboxylic acids. For instance, the keto-enol equilibrium constant of malonic acid in diluted aqueous solution is <10(-4). Our results suggest that in deliquesced micrometer-size particles, carboxylic acids may exist in predominantly enol forms that need to be explicitly considered in atmospheric aerosol chemistry.
53 citations
TL;DR: The objective of this study was to identify a source of intramitochondrial malonyl-CoA that could be used for de novo fatty acid synthesis in mammalian mitochondria and found the mitochondrial ACSF3 enzyme is capable of filling this role by utilizing free malonic acid as substrate.
TL;DR: In this paper, a series of 1D nano-sized MOFs with 1D channels, [Ln(2,5-pzdc)(ox)0.5(H2O)2]·4.5H 2O (1-Ln; Ln = Nd, Sm, Eu, Gd, Tb, Dy), were obtained by formal carboxyl transfer.
Abstract: Reacting lanthanide nitrates with 2,5-pyrazinedicarboxylic acid (2,5-pzdcH2) and oxalic acid (oxH2) hydrothermally at 140 °C yielded a series of MOFs with 1D nano-sized channels, [Ln(2,5-pzdc)(ox)0.5(H2O)2]·4.5H2O (1-Ln; Ln = Nd, Sm, Eu, Gd, Tb, Dy), different from previously reported ultra-microporous [Ln(2,5-pzdc)1.5(H2O)3]·0.5H2O. While the oxalic acid was replaced by other dicarboxylic acids like terephthalic acid, malonic acid, glutaric acid, or pyrazole-3,5-dicarboxylic acid, obtained was a novel series of 1D polymers, [Ln(2,5-pzdc)0.5(2,6-pzdc)(H2O)3] (2-Ln; Ln = Pr, Sm, Eu, Tb; 2,6-pzdc2− = 2,6-pyrazinedicarboxylate), with 2,6-pzdc2− formed in situ by formal carboxyl transfer. This represents the first example of carboxyl transfer either in coordination compounds or in hydrothermal synthesis. The Eu and Tb complexes in these two series emit strong ligand sensitized f–f luminescence.
TL;DR: There appeared to be no competition between their individual pathways, and many metabolites were induced by mechanical stress, including RA and some of its derivatives, most ACs, hydroxycinnamic acids and flavonoids, whereas the abundance of some RA dimers was reduced.
TL;DR: The purpose of this research was to develop new strains of Escherichia coli with improved fatty acid biosynthesis with a strong preference for acetyl-CoA and to observe the effects of overexpression, the production of malonic acid, a pathway intermediate, and fatty acids was analyzed.
Abstract: The purpose of this research was to develop new strains of Escherichia coli with improved fatty acid biosynthesis. β-Ketoacyl acyl carrier protein synthase III (fabH) catalyzes the first step in the synthesis of fatty acids in parallel with acetyl-CoA carboxylase (accABC) and malonyl-CoA: acyl carrier protein transacylase (fabD) in Escherichia coli K-12 MG1655. The enzyme encoded by the fabH gene leads to an increase in the synthesis of short-chain-length fatty acids and a strong preference for acetyl-CoA, as it produces only straight chain fatty acids (SCFAs). It also seems to play a role in determining the type and composition of fatty acids produced. In this study, metabolically engineered strains of E. coli K-12 MG1655 containing fabH or accA::accBC::fabD or accA::accBC:: fabD::fabH gene-inserted expression vector (pTrc99A) were constructed. To observe the effects of overexpression, the production of malonic acid, a pathway intermediate, and fatty acids was analyzed. The resulting recombinant strains produced total lipids up to approximately 1.2 ∼ 1.6 fold higher than that of wild-type E. coli. The production of hexadecanoic acid was especially enhanced up to approximately 4.8 fold in E. coli SGJS13 as compared to E. coli SGJS11.
TL;DR: In this article, the mechanism and the final outcome of the Knoevenagel-Doebner reaction are discussed, where the condensation reaction between different hydroxy-substituted aromatic aldehydes and malonic acid is performed using piperidine as organocatalyst.
Abstract: The mechanism and the final outcome of the Knoevenagel-Doebner reaction are discussed. The condensation reaction between different hydroxy-substituted aromatic aldehydes and malonic acid is performed using piperidine as organocatalyst. The key role of the catalyst is clearly pointed out during the decarboxylation of ferulic acid, without the use of a strong decarboxylating agent, leading to a 4-vinylphenol derivative. Based on the results obtained, the studied pathway may be important in the understanding of vinylphenol production during malting and brewing of wheat and barley grains. Finally, changing the solvent of the reaction from pyridine to water in the Knoevenagel-Doebner reaction of 4-hydroxybenzaldehydes, dimerization of resulting styrene derivatives is observed. These results can be of interest also in the field of food chemistry, since cinnamic acids are frequently found in fruits and vegetables used for human consumption.
TL;DR: In this paper, the ternary complexes of copper(II) involving promethazine, N,N-dimethyl-3-(phenothiazin-10-yl)propylamine (Prom) and various biologically relevant ligands containing different functional groups, were investigated.
Abstract: Binary and ternary complexes of copper(II) involving promethazine, N,N-dimethyl-3-(phenothiazin-10-yl)propylamine (Prom) and various biologically relevant ligands containing different functional groups, were investigated. The ligands (L) are dicarboxylic acids, amino acids, amides and DNA constituents. The ternary complexes of amino acids, dicarboxylic acids or amides are formed by simultaneous reactions. The results showed the formation of Cu(Prom)(L) complexes with amino acids and dicarboxylic acids. The effect of chelate ring size of the dicarboxylic acid complexes on their stability constants was examined. Amides form both Cu(Prom)(L) complexes and the corresponding deprotonated species Cu(Prom)(LH−1). The ternary complexes of copper(II) with (Prom) and DNA are formed in a stepwise process, whereby binding of copper(II) to (Prom) is followed by ligation of the DNA components. DNA constituents form both 1:1 and 1:2 complexes with Cu(Prom)2+. The stability of these ternary complexes was quantitatively compared with their corresponding binary complexes in terms of the parameters Δlog10K. The values of Δlog10K indicate that the ternary complexes containing aromatic amino acids were significantly more stable than the complexes containing alkyl- and hydroxyalkyl-substituted amino acids. The concentration distribution of various complex species formed in solution was also evaluated as a function of pH. The solid complexes [Cu(Prom)L)] where L=1,1-cyclobutanedicarboxylic acid (CBDCA), oxalic and malonic acid were isolated and characterized by elemental analysis, infrared, TGA, and magnetic susceptibility measurements. Spectroscopic studies of the complexes revealed that the complexes exhibits square planar coordination with copper(II). The isolated solid complexes have been screened for their antimicrobial activities using the disc diffusion method against some selected bacteria and fungi. The activity data show that the metal complexes are found to have antibacterial and antifungal activity.
TL;DR: All new compounds were characterized by IR, NMR spectroscopy, DSC, and elemental analysis and their energetic properties, such as impact sensitivity, detonation velocity, and detonation pressure were determined and compared with existing energetic compounds.
Abstract: Reaction of 2,2-dinitro-1,3-propanediol (1) with oxalyl dichloride or malonyl dichloride in refluxing ether led to the formation of cyclic dinitro-containing esters (2, 3) in very good yields. Compounds 2 and 3 were also isolated in similar yields by the treatment of 1 with oxalic acid or malonic acid in trifluoroacetic anhydride at room temperature. Nitration of 3 with fuming nitric acid resulted in the corresponding trinitro cyclic ester 4 in 70 % isolated yield. Treatment of 1 with a large excess of methanolic ammonia gave impure 2,2-dinitro-1,3-diaminopropane (5). Polynitraamines, 7 and 11, were treated with aqueous ammonia, hydrazine monohydrate or hydroxylamine in methanol at room temperature to obtain their corresponding salts 8–10 and 12–14, respectively, in excellent isolated yields. All new compounds were characterized by IR, NMR spectroscopy (1H, 13C, 15N), DSC, and elemental analysis. Their energetic properties, such as impact sensitivity, detonation velocity, and detonation pressure were also determined and compared with existing energetic compounds, such as PETN (pentaerythritol tetranitrate), RDX (1,3,5-trinitro-1,3,5-triazacyclohexane), and TNT (trinitrotoluene).
TL;DR: From an environmental perspective, this work is the first experimental demonstration that dicarboxylic acids present in the cryosphere might be subject to photochemical degradation into smaller organic acids and carbon dioxide.
Abstract: To better understand the oxidation of organic species by OH within frozen solutions, experiments were conducted with a simplified model system consisting of succinic acid (2.5, 5, and 10 mM), using H2O2 (30 mM) as a condensed-phase OH precursor. Frozen (−20 °C) and aqueous (0 °C and room temperature) solutions were irradiated using a xenon arc lamp to study the differences between frozen and nonfrozen reaction media. Formation of products and decay of reactants were measured using ion chromatography (IC) and gas chromatography–mass spectrometry (GC–MS). Malonic acid was observed as the dominant product, with malic acid formed in significantly smaller amounts, in both frozen and unfrozen substrates, suggesting a common mechanism independent of phase. Notably, a large decrease was observed in the succinic acid first-order decay rate constant when moving from aqueous to frozen samples. This is due not to temperature-dependent second-order kinetics or different OH production rates between the samples, but ins...
TL;DR: In this paper, the photocatalytic degradation of malic acid was studied under ambient conditions in an aqueous TiO(2) suspension, and the results demonstrated the presence of four distinct mineralization rate variations over the course of its degradation.
Abstract: The photocatalytic degradation of malic acid was studied under ambient conditions in an aqueous TiO(2) suspension. The results demonstrated the presence of four distinct mineralization rate variations over the course of its degradation. Differences in the mineralization rate were governed by the dominant intermediate present in the solution at that time. Initial mineralization was rapid (similar to 175 mu g C/min) resulting from the swift extraction of a carbon from strongly adsorbed malic acid via the photo-Kolbe mechanism. The mineralization rate then slowed down (similar to 50-70 mu g C/min) with the continued formation of an intermediate product (believed to be malonaldehydic acid), malonic acid and acetic acid in the solution. The findings provide greater insight into the photocatalytic degradation mechanism, illustrating the importance of intermediates and their attributes in relation to the overall rate of organic removal.
Patent•
28 Feb 2011
Abstract: An etchant composition for formation of metal lines is provided to secure stability of etchant and uniform etching performance, thereby preventing damage to underlayer and equipment An etchant composition for formation of metal lines comprises H3PO4 40~70 weight%, HNO3 2~10 weight%, CH3COOH 5~20 weight%, organic acid 01~5 weight% except for CH3COOH, phosphate 01~5 weight%, a compound including amino radical and carboxyl group 01~5 weight%, and the rest water The organic acid except for CH3COOH is made of one or two selected from the group consisting of butanoic acid, citric acid, formic acid, gluconic acid, glycolic acid, malonic acid, oxalic acid, pentanoic acid, and other water-soluble organic acid The phosphate is made of sodium dihydrogen phosphate or/and otassium dihydrogen phosphate The compound including compound including amino radical and carboxyl group is made of one or two selected from the group consisting of alanine compound, aminobutyric acid compound, glutamic acid compound, glycine compound, iminodiacetic acid compound, nitrilotriacetic acid compound, and sarcosine compound
TL;DR: The results indicated that the optimum biocatalyst for 3-CPA biodegradation was the resting cells, and the mechanism of the dehalogenase-catalyzed reaction was inferred as hydrolytic dehalagenation which was coenzyme A-independent and oxygen-independent.
Abstract: In this study, a bacterial Bacillus sp. CGMCC no. 4196 was isolated from mud. This strain exhibited the ability to degrade high concentration of 3-chloropropionate (3-CPA, 120 mM) or 3-chlorobutyrate (30 mM), but not chloroacetate or 2-chloropropionate (2-CPA). The growing cells, resting cells, and cell-free extracts from this bacterium had the capability of 3-CPA degradation. The results indicated that the optimum biocatalyst for 3-CPA biodegradation was the resting cells. The 3-CPA biodegradation pathway was further studied through the metabolites and critical enzymes analysis by HPLC, LC-MS, and colorimetric method. The results demonstrated that the metabolites of 3-CPA were 3-hydroxypropionic acid (3-HP) and malonic acid semialdehyde, and the critical enzymes were 3-CPA dehalogenase and 3-HP dehydroxygenase. Thus, the mechanism of the dehalogenase-catalyzed reaction was inferred as hydrolytic dehalogenation which was coenzyme A-independent and oxygen-independent. Finally, the pathway of β-chlorinated aliphatic acid biodegradation could be concluded as follows: the β-chlorinated acid is first hydrolytically dehalogenated to the β-hydroxyl aliphatic acid, and the hydroxyl aliphatic acid is oxidized to β-carbonyl aliphatic acid by β-hydroxy aliphatic acid dehydroxygenase. It is the first report that 3-HP was produced from 3-CPA by β-chlorinated aliphatic acid dehalogenase.
TL;DR: According to the activity studies, 3-arylalkyl-6-(p-chlorophenyl) derivatives were found to be protective against scMet, whereas 6-phenyl derivatives were not and 6-Phenyl-3-(2-morpholinoethyl)hexahydropyrimidine-2,4-dione was the only compound determined to be active against MES at 300 mg/kg dose at half an hour.
Abstract: In this study, some new 3-alkyl-6-arylhexahydropyrimldine-2,4-dione derivatives were synthesized as anticonvulsant agents. 6-Arylhexahydropyrimidine-2,4-diones which were used as starting materials in the synthesis of the compounds were prepared in acidic media by the cyclization of potassium cyanate and the appropriate ureido acids that were gained by the reaction of β-aminoacids, malonic acid and ammonium acetate. The structures of the synthesized compounds were confirmed by UV, IR, 1 H-NMR and elementary analysis. Their anticonvulsant activities were determined by maximal electroshock (MES), subcutaneous metra-zol (scMet) and rotorod toxicity tests for neurological deficits. According to the activity studies, 3-arylalkyl-6-(p-chloro-phenyl) derivatives were found to be protective against scMet, whereas 6-phenyl derivatives were not 6-Phenyl-3-(2-mor-pholinoethyl)hexahydropyrimidine-2,4-dione was the only compound determined to be active against MES at 300 mg/kg dose at half an hour.
TL;DR: The Cd(II)H2L complex induced perturbation of the cell cycle phase distribution and an increase in the percentage of cells in the sub‐G1 phase of human cervical cancer HeLa cell line and murine melanoma B16 cell line.
Abstract: Organometallic Cd(II) compounds have recently attracted attention for their anticancer activity. The interaction of the dinuclear complex of Cd(II) with the condensation product of 2-acetylpyridine and malonic acid dihydrazide, N′,N′2-bis[(1E)-1-(2-pyridyl)ethylidene]propanedihydrazide (Cd(II)H2L), with calf thymus DNA (CT-DNA) was monitored by blue shift in UV–vis spectra of the complex. The binding constant of Cd(II)H2L complex with CT-DNA was determined (KB = 1.8 × 104 M−1) and was indicative of minor groove binding. Agarose gel electrophoretic changes in mobility of supercoiled and circular forms of pBR322 and pUC18 plasmids in the presence of the complex suggest that conformational changes in the plasmids occur upon binding of the Cd(II)H2L complex. The Cd(II)H2L complex induced perturbation of the cell cycle phase distribution and an increase in the percentage of cells in the sub-G1 phase of human cervical cancer HeLa cell line and murine melanoma B16 cell line. Immunoblotting analysis showed the overexpression of Bcl-2 protein with the Cd(II)H2L complex. © 2010 Wiley Periodicals, Inc. J Biochem Mol Toxicol 25:175–182 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/jbt.20374
TL;DR: In this article, the domino reaction of ethyl diazoacetate, carbon monoxide and ferrocenylimines was investigated in the presence of Co2(CO)8 as catalyst.
TL;DR: In this paper, the performance of the Li salt of (S )- or ( R )-3,3′-bis[bis-(phenyl)hydroxymethyl]-2,2′-dihydroxy-dinaphthalene-1,1′ (BIMBOL) in asymmetric Michael additions of malonic acid derivatives and toluedine has been studied.
Abstract: The catalytic performance of the Li salt of ( S )- or ( R )-3,3′-bis[bis-(phenyl)hydroxymethyl]-2,2′-dihydroxy-dinaphthalene-1,1′ (BIMBOL) in asymmetric Michael additions of malonic acid derivatives and toluedine has been studied. Nitrostyrene and cyclohex-2-enone were chosen as Michael acceptors. Efficient asymmetric C–C and C–N bond formations with ee’s of up to 95% at room temperature were observed. A transition state model of the malonic ester addition to cyclohex-2-enone has been proposed based on the molecular structure of the acetone solvate of BIMBOL. The impact of the catalyst self-association on its performance is also discussed.
TL;DR: By studying in vitro gene delivery an increase of transfection efficacy was observed when using lipids with at least one unsaturated alkyl chain, which leads to cationic lipids exhibiting comparable or even higher transfectation efficacies compared to the commercially available transfections agents LipofectAmine™ and SuperFect™.
TL;DR: In this article, single crystals of copper malonate trihydrate were grown in silica gel by slow diffusion of copper nitrate by sodium metasilicate gel impregnated with malonic acid.
TL;DR: In this paper, the effect of the ambient relative humidity (RH) on the crystallization of malonic and glutaric acid in aqueous microdroplets was investigated using an electrodynamic balance (EDB).
Abstract: The effect of the ambient relative humidity (RH) on the crystallization of malonic and glutaric acid in aqueous microdroplets was investigated using an electrodynamic balance (EDB). Aqueous droplets containing a solute were injected into a chamber maintained at selected RH values, after which the RH was cycled to characterize crystallization and deliquescence behavior. Glutaric acid crystals that were formed at >40% RH deliquesced at 85 ± 2% RH, consistent with the metastable α polymorph. Glutaric acid crystals initially formed at ≤30% RH, however, deliquesced at 90 ± 2% RH, corresponding to the stable β polymorph. These polymorph identifications were confirmed using in situ Raman spectroscopy. In the case of malonic acid, the mass change measured with the EDB at deliquescence revealed the formation of a hydrate, C3H4O4·1.5H2O, when the crystals were initially formed at ≥20% RH. The EDB response for malonic acid crystals initially formed at ∼5% RH, however, corresponded to an anhydrous form. These observa...
Patent•
07 Feb 2011
TL;DR: In this paper, the acid residues of poly(poly-)glycerol partial ester having a number average of 0.005-0.75-2.5 residues of at least one carboxylic acid with 10-24 carbon atoms were analyzed.
Abstract: (Poly-)glycerol partial ester having a number average of 0.75-2.25 acid residues of at least one carboxylic acid with 10-24 carbon atoms and a number average of 0.005-0.5 residues of a polyfunctional carboxylic acid, preferably dimer fatty acids, oxalic acid and fumaric acid, comprises polyfunctional carboxylic acid ester(poly-)glycerol partial ester with a condition that after complete hydrolysis of (poly-)glycerol partial ester, a (poly-)glycerol is obtained, which exhibits a homologous distribution with glycerol, diglycerol, triglycerol, tetraglycerol, pentaglycerol and oligoglycerol. (Poly-)glycerol partial ester having a number average of 0.75-2.25 acid residues of at least one carboxylic acid with 10-24 carbon atoms and a number average of 0.005-0.5 residues of a polyfunctional carboxylic acid, preferably dimer fatty acids, oxalic acid, fumaric acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, malic acid, tartaric acid, tartronic acid, maleic acid, citric acid, phthalic acid, isophthalic acid or terephthalic acid, comprises polyfunctional carboxylic acid ester(poly-)glycerol partial ester with a condition that after complete hydrolysis of (poly-)glycerol partial ester, a (poly-)glycerol is obtained, which exhibits a homologous distribution with glycerol (0.01-20 wt.%), diglycerol (0.01-60 wt.%), triglycerol (0.01-60 wt.%), tetraglycerol (0.01-30 wt.%), pentaglycerol (0.01-20 wt.%) and oligoglycerol (made upto 100 wt.%). Independent claims are also included for: (1) producing the (poly-)glycerol partial ester, comprising (a) providing a (poly-)glycerol, (b) esterifying a part of the (poly-)glycerol with at least one carboxylic acid having 10-24C, and (c) further esterifying with a polyfunctional carboxylic acid, where the molar ratio of the polyfunctional carboxylic acid used in process step (c) to the (poly-)glycerol used in process step (a), is 1:2-1:200; (2) an emulsifier comprising the (poly-)glycerol partial ester; and (3) a cosmetic or a pharmaceutical formulation comprising the (poly-)glycerol partial ester.
TL;DR: The electronic and steric impact of the substituents on the kinetics of ring expansion of N-vinyl aziridines to pyrrolines has been studied and various diversely substituted novel pyrroline derivatives have been synthesized by this methodology and the products can be used as key intermediates in the synthesis of substituted pyrrole-4,4-dicarboxylic acid diethyl esters.
Abstract: A novel synthetic methodology has been developed for the synthesis of diethyl 5-alkyl/aryl/heteroaryl substituted 3,4-dihydro-2H-pyrrole-4,4-dicarboxylates (also called 2-substituted pyrroline-4,5-dihydro-3,3-dicarboxylic acid diethyl esters) by iodide ion induced ring expansion of 2-[(aziridin-1-yl)-1-alkyl/aryl/heteroaryl-methylene]malonic acid diethyl esters in very good to excellent yields under mild reaction conditions. The electronic and steric impact of the substituents on the kinetics of ring expansion of N-vinyl aziridines to pyrrolines has been studied. Various diversely substituted novel pyrroline derivatives have been synthesized by this methodology and the products can be used as key intermediates in the synthesis of substituted pyrrolines, pyrroles and pyrrolidines.