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Zhao Huazhang - - 2012
Electrochemical reduction of carbon dioxide (CO2) to useful chemical materials is of great significance to the virtuous cycle of CO2. However, some problems such as high overpotential, high applied voltage and high energy consumption exist in the course of the conventional electrochemical reduction process. This study presents a new CO2 ...
Wuensch Christiane - - 2012
The enzymatic carboxylation of phenol and styrene derivatives using (de)carboxylases in carbonate buffer proceeded in a highly regioselective fashion: Benzoic acid (de)carboxylases selectively formed o-hydroxybenzoic acid derivatives, phenolic acid (de)carboxylases selectively acted at the β-carbon atom of styrenes forming (E)-cinnamic acids.
Kimura Ken-Ichi - - 2012
A new compound, 15,20-dinor-5,7,9-labdatriene-18-ol (1), named kujigamberol, was isolated from amber, fossilized tree resin from the Kuji area in Japan, has been dated as being 85Ma old (late Cretaceous). Kujigamberol was identified using the hypersensitive mutant yeast (zds1∆ erg3∆ pdr1∆ pdr3∆) with respect to Ca(2+)-signal transduction. The structure was elucidated ...
Kauffman Marcelo Andrés - - 2012
Cerebrotendinous xanthomatosis (CTX) is a treatable disorder of bile acid production caused by mutations in the mitochondrial enzyme sterol 27-hydroxilase. This inborn error of bile acid metabolism results in lipid pathologic accumulation in multiple tissues. Progressive neuropsychiatric disturbances are a frequent manifestation of this disease. Although seizures have been frequently ...
Radhika Parvataneni - - 2012
Phytochemical investigation of the methanolic extract of the leaves of Andrographis paniculata Nees yielded a minor, new diterpene, 21-nor-3,19-isopropylidine-14-deoxy-ent-labda-8(17),13-dien-16,15-olide (1), together with five known labdane type diterpenes, andrographolide 3, 14-deoxyandrographolide 4, 14-deoxy-12-hydroxyandrographolide 5, 14-deoxy-11,12-dihydroandrographolide 6, neoandrographolide 7, and two acids, cinnamic acid 8, and ferulic acid 9. The chemical structures ...
Jariwala Freneil B - - 2012
In the negative-ion collision-induced dissociation mass spectra of most organic sulfonates, the base peak is observed at m/z 80 for the sulfur trioxide radical anion (SO(3) (-·) ). In contrast, the product-ion spectra of a few sulfonates, such as cysteic acid, aminomethanesulfonate, and 2-phenylethanesulfonate, show the base peak at m/z ...
Shao Meng - - 2012
Four new triterpenoids, psiguanins A-D (1-4), along with 13 known ones (5-17), were isolated from the leaves of Psidium guajava. The structures of new compounds were determined as 2α,3β-dihydroxy-taraxer-20-en-28-oic acid (1), 2α,3β,12α,13β-tetrahydroxy-urs-28-oic acid (2), 2α,3β,12β,13β-tetrahydroxy-urs-28-oic acid (3), and 2α,3β,12β,13α-tetrahydroxy-urs-28-oic acid (4), respectively, on the basis of comprehensive spectroscopic methods and ...
Bednarczyk-Cwynar Barbara - - 2012
Amide formation is one of the reactions that can be undertaken within the carboxyl group of oleanolic acid. A simple method for oleanolic acid anilide and toluidides synthesis is presented. The influence of the location of the methyl substituent on the reactivity of the amine group was tested and the ...
Mukherjee Tulika - - 2012
Chemical investigation of the leaves of Putranjiva roxburghii has resulted in the isolation of two new triterpenoids, putralone, a novel 10alpha-hydroxy-25-nor D:A friedo-olean-9(11)-en-3 one and 3beta-acetoxy-cycloart-24-en-23-one, along with a rare hopanoid, adian-5-en-3beta,29-diol. Other known triterpenoids isolated from this plant are 3beta-acetoxy-adian-5-ene, putrol, putrone, putranjivadione, roxburghonic acid, friedelin, friedlan-3alpha-ol, oleanolic acid ...
Fayek Nesrin M - - 2012
Manilkara zapota (L.) Van Royen is an evergreen tree, native to the tropical Americas and introduced to Egypt as a fruiting tree in 2002. No previous study was reported on the plant cultivated in Egypt. In this study, the leaves of the plant cultivated in Egypt were subjected to phytochemical ...
Bevilacqua Lorenzo - - 2012
The aim of this clinical trial was to compare clinical and biochemical healing outcomes following ultrasonic mechanical instrumentation versus ultrasonic mechanical instrumentation associated with topical subgingival application of amino acids and sodium hyaluronate gel. Eleven systemically healthy subjects with moderate-severe chronic periodontitis, who had four sites with pocket probing depth ...
Dos Santos Fernanda M - - 2012
This work describes the phytochemical study of the extracts from aerial parts of Tibouchina candolleana as well as the evaluation of the antimicrobial activity of extracts, isolated compounds, and semi-synthetic derivatives of ursolic acid against endodontic bacteria. HRGC analysis of the n-hexane extract of T. candolleana allowed identification of β-amyrin, ...
Hopkins Todd Anthony - - 2012
The chiral discrimination ability of amino acid based chiral ionic liquids is studied using chiroptical luminescence techniques. A racemic mixture of dissymmetric europium tris 2,6-pyridinedicarboxylate complexes are dissolved in five chiral ionic liquids, including L- and D-alanine methyl ester bis(trifluoromethanesulfonimide), L-leucine methyl ester bis(trifluoromethanesulfonimide), L-proline methyl ester bis(trifluoromethanesulfonimide), and tetrabutylammonium ...
Barros Helena Rudge de Moraes - - 2012
Four Citrus species (C. sinensis, cvs. Pera and Lima; C. latifolia Tanaka cv. Tahiti; C. limettioides Tanaka cv. Sweet lime and C. reticulate, cv. Ponkan) grown in Brazil were characterised in relation to contents of minerals, ascorbic acid, total polyphenols and antioxidant capacity of pulps and peels. In general, the ...
Baslé Olivier - - 2012
Phosphine-boronates R(2)P(o-C(6)H(4))B(OR')(2) have been evaluated as bifunctional organocatalysts for the Michael addition of malonate pronucleophiles to methylvinylketone. The presence of the Lewis acidic boron center adjacent to phosphorus significantly improves catalytic performance. Isolation and complete characterization of a key intermediate, namely a β-phosphonium enolate, substantiate the role of the Lewis ...
Huang Hung-Yi - - 2012
Bioassay-guided fractionation of the roots of Anneslea fragrans var. lanceolata led to the isolation of four dihydrochalcone glucosides, davidigenin-2'-O-(6″-O-4″'-hydroxybenzoyl)-β-glucoside (1), davidigenin-2'-O-(2″-O-4″'-hydroxybenzoyl)-β-glucoside (2), davidigenin-2'-O-(3″-O-4″'-hydroxybenzoyl)-β-glucoside (3), and davidigenin-2'-O-(6″-O-syringoyl)-β-glucoside (4), and 13 known compounds. The structures were identified by means of spectroscopic analysis. Davidigenin-2'-O-(6″-O-syringoyl)-β-glucoside (4), 1-O-3,4-dimethoxy-5-hydroxyphenyl-6-O-(3,5-di-O-methylgalloyl)-β-glucopyranoside (5), lyoniresinol (10), and syringic acid (13) ...
Ferchichi Loubna - - 2012
Advanced glycation end-products (AGEs) are associated with many pathogenic disorders such as Alzheimer's disease, pathogenesis of diabetes, atherosclerosis or endothelial dysfunction leading to cardiovascular events. Clusiaceae and Calophyllaceae families are rich in compounds like polyphenols which are able to inhibit their formation and are therefore of great interest. Calophyllum flavoramulum ...
Duckstein Sarina M - - 2012
INTRODUCTION: Hamamelis virginiana, known for its high level of tannins and other phenolics is widely used for treatment of dermatological disorders. Although reports on hydroalcoholic and aqueous extracts from Hamamelis leaf and bark exist, knowledge on fermented leaf preparations and the underlying conversion processes are still scant. OBJECTIVE: Aqueous Hamamelis ...
Saini Ratni - - 2012
A stereoselective synthesis of (25S)-Δ(1)-, (25S)-Δ(1,4)-, (25S)-Δ(1,7)-, (25S)-Δ(8(14))-, (25S)-Δ(4,6,8(14))-dafachronic acid, methyl (25S)-Δ(1,4)-dafachronate and (25S)-5α-hydroxy-3,6-dioxocholest-7-en-26-oic acid is described. (25S)-Δ(1,4)-Dafachronic acid and its methyl ester are natural products isolated from corals and have been obtained by synthesis for the first time. (25S)-5α-Hydroxy-3,6-dioxocholest-7-en-26-oic acid represents a promising synthetic precursor for cytotoxic marine steroids.
Rattanaburi Suthida - - 2012
A new chromone, 5,7-dihydroxy-2 -(hydroxymethyl)-6,8-dimethyl-chromen-4-one, named melachromone, together with 12 known compounds, including chromones, anthraquinone, flavonoids, flavonoid glycosides, benzene derivatives, ellagic acids and terpenes, were isolated from the leaves of Melaleuca cajuputi Powell. Their structures were characterised by spectroscopic methods.
Scott William G - - 2012
The process of building and refining crystal structures of nucleic acids, although similar to that for proteins, has some peculiarities that give rise to both various complications and various benefits. Although conventional isomorphous replacement phasing techniques are typically used to generate an experimental electron-density map for the purposes of determining ...
McGinty D - - 2012
A toxicologic and dermatologic review of 1,1-dimethyl-2-phenylethyl acetate when used as a fragrance ingredient is presented. 1,1-Dimethyl-2-phenylethyl acetate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an Aryl Alkyl Alcohol with a simple carboxylic acid ...
McGinty D - - 2012
A toxicologic and dermatologic review of piperonyl acetate when used as a fragrance ingredient is presented. Piperonyl acetate is a member of the fragrance structural group aryl alkyl alcohol simple acid esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid ...
Karlsson Niclas G - - 2012
The O-linked glycosylation of the main acidic high molecular weight glycoprotein from ascites fluid from patients with ovarian cancer were analysed. The O-linked oligosaccharides were shown to consist of mainly highly sialylated core 1 and core 2 structures with a smaller amount of sulfated core 2 structures. These structures were ...
Hu Youcai - - 2012
Erythrolic acids A-E (1-5) are five unusual meroterpenoids isolated from the bacterium Erythrobacter sp. derived from a marine sediment sample collected in Galveston, TX. The structures were elucidated by means of detailed spectroscopic analysis and chemical derivatization. The erythrolic acids contain a 4-hydroxybenzoic acid appended with a modified terpene side ...
Choma Adam - - 2012
The structure of the lipid A of the lipopolysaccharide (LPS) from Azorhizobium caulinodans, a symbiont of the tropical legume Sesbania rostrata, was investigated by chemical compositional analyses, mass spectrometry, as well as 1D and 2D NMR spectroscopy techniques. The lipid A backbone was composed of a β-(1→6)-linked 2,3-diamino-2,3-dideoxy-d-glucopyranose (GlcpN3N) disaccharide ...
Vaz Fernando Antonio Simas - - 2012
INTRODUCTION: Aluminum toxicity is commonly verified in acidic soils, and poses a severe limitation to plant growth and development. Therefore, Al complexation by the root system mucilage, Al complexation by organic compounds that are exuded by the roots and internal metabolic processes must be monitored by organic acids (OA), since ...
Kováčik Jozef - - 2012
Phenolic metabolism of Al-exposed Matricaria chamomilla plants was modulated with four regulators: 2-aminoindane-2-phosphonic acid (AIP), salicylic acid (SA), sodium nitroprusside (SNP) and dithiothreitol (DTT). Physiological parameters (tissue water content, soluble proteins, reducing sugars, K(+) content), root lignin content and free amino acids (increase in root proline and alanine) were the ...
Lu Pei-Pei - - 2012
Polyethersulfone (PES)/perfluorosulfonic acid (PFSA) nanofiber membranes were successfully fabricated via electrospinning method from polymer solutions added with calcium carbonate (CaCO3) nanoparticles. ATR-FTIR spectra indicated that the nanoparticles mainly existed on the external surface of the nanofibers and could be removed completely by acid treatment. Surface roughness of both the nanofibers ...
McGinty D - - 2012
A toxicologic and dermatologic review of 2-phenoxyethyl propionate when used as a fragrance ingredient is presented. 2-Phenoxyethyl propionate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid ...
McGinty D - - 2012
A toxicologic and dermatologic review of 2-phenylpropyl acetate when used as a fragrance ingredient is presented. 2-Phenylpropyl acetate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid ...
McGinty D - - 2012
A toxicologic and dermatologic review of p-anisyl acetate when used as a fragrance ingredient is presented. p-Anisyl acetate is a member of the fragrance structural group aryl alkyl alcohol simple acid esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid ...
Ghosh Shibaji K - - 2012
The absolute configuration (via degradation and Marfey's derivatization studies) and the total synthesis of a novel antimalarial lipid-peptide isolated from Streptomyces sp. (IC(50) = 0.8 μM, Plasmodium falciparum 3D7) is disclosed. To this end, versatile stereocontrolled routes to nonproteinogenic amino acids (via catalytic Mannich, Sharpless methods) and enantiomeric trans fatty ...
McGinty D - - 2012
A toxicologic and dermatologic review of anisyl formate when used as a fragrance ingredient is presented. Anisyl formate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid ...
Liu Qiang - - 2012
Carbonate was added into a co-culture of glucose and fresh leachate under alkaline condition to enhance batched acidogenesis and fermentative hydrogen production simultaneously. Results indicated carbonate has positive effect on both H(2) production and acetic acid generation. The highest hydrogen yield (about 1.40mol/mol glucose) was obtained at [CO(3)(2-)]=280mg/L with pH ...
McGinty D - - 2012
A toxicologic and dermatologic review of 3-phenyl-3-buten-1-yl acetate when used as a fragrance ingredient is presented. 3-Phenyl-3-buten-1-yl acetate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid ...
McGinty D - - 2012
A toxicologic and dermatologic review of 1,1-dimethyl-2-phenylethyl butyrate when used as a fragrance ingredient is presented. 1,1-Dimethyl-2-phenylethyl butyrate is a member of the fragrance structural group aryl alkyl alcohol simple acid esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid ...
Ríos María Yolanda - - 2012
Complete (1) H and (13) C NMR chemical shift assignments for 3,4-seco-lup-20(29)-en-3-oic acid (1) have been established by means of two-dimensional COSY, HSQC, HMBC and NOESY spectroscopic experiments as well as by analysis of MS data. Compound 1 was isolated from Decatropis bicolor (Zucc.) Radlk. (Rutaceae) in addition to six ...
McGinty D - - 2012
A toxicologic and dermatologic review of 4-methylbenzyl acetate when used as a fragrance ingredient is presented. 4-Methylbenzyl acetate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid ...
McGinty D - - 2012
A toxicologic and dermatologic review of 2,4-dimethylbenzyl acetate when used as a fragrance ingredient is presented. 2,4-Dimethylbenzyl acetate is a member of the fragrance structural group aryl alkyl alcohol simple acid esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid ...
McGinty D - - 2012
A toxicologic and dermatologic review of phenethyl acetate when used as a fragrance ingredient is presented. Phenethyl acetate is a member of the fragrance structural group aryl alkyl alcohol simple acid esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid ...
McGinty D - - 2012
A toxicologic and dermatologic review of 2-methyl-4-phenyl-2-butyl acetate when used as a fragrance ingredient is presented. 2-Methyl-4-phenyl-2-butyl acetate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid ...
McGinty D - - 2012
A toxicologic and dermatologic review of carbonic acid, methyl phenylmethyl ester when used as a fragrance ingredient is presented. Carbonic acid, methyl phenylmethyl ester is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl ...
McGinty D - - 2012
A toxicologic and dermatologic review of 3-phenylpropyl acetate when used as a fragrance ingredient is presented. 3-Phenylpropyl acetate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid ...
McGinty D - - 2012
A toxicologic and dermatologic review of 1,1-dimethyl-2-phenylethyl propionate when used as a fragrance ingredient is presented. 1,1-Dimethyl-2-phenylethyl propionate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid ...
McGinty D - - 2012
A toxicologic and dermatologic review of anisyl acetate when used as a fragrance ingredient is presented. Anisyl acetate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid ...
McGinty D - - 2012
A toxicologic and dermatologic review of α-methylbenzyl acetate when used as a fragrance ingredient is presented. α-Methylbenzyl acetate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid ...
McGinty D - - 2012
A toxicologic and dermatologic review of 1,1-dimethyl-2-phenylethyl formate when used as a fragrance ingredient is presented. 1,1-Dimethyl-2-phenylethyl formate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid ...
McGinty D - - 2012
A toxicologic and dermatologic review of benzyl formate when used as a fragrance ingredient is presented. Benzyl formate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid ...
McGinty D - - 2012
A toxicologic and dermatologic review of 1-phenyl-3-methyl-3-pentyl acetate when used as a fragrance ingredient is presented. 1-Phenyl-3-methyl-3-pentyl acetate is a member of the fragrance structural group Aryl Alkyl Alcohol Simple Acid Esters (AAASAE). The AAASAE fragrance ingredients are prepared by reacting an aryl alkyl alcohol with a simple carboxylic acid ...
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