Search Results
Results 351 - 400 of 1380
< 3 4 5 6 7 8 9 10 11 12 13 >
McGinty D - - 2012
A toxicologic and dermatologic review of anisyl propionate when used as a fragrance ingredient is presented. Anisyl 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 phenethyl formate when used as a fragrance ingredient is presented. Phenethyl 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 1,3-dimethyl-3-phenylbutyl acetate when used as a fragrance ingredient is presented. 1,3-Dimethyl-3-phenylbutyl 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 propionate when used as a fragrance ingredient is presented. α-Methylbenzyl 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-hydroxy-2-phenylethyl acetate when used as a fragrance ingredient is presented. 2-Hydroxy-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 phenethyl propionate when used as a fragrance ingredient is presented. Phenethyl 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 p-isopropylbenzyl acetate when used as a fragrance ingredient is presented. p-Isopropylbenzyl 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 ...
Wang Xiumei - - 2012
Two ways: A Zn-modified ZSM-5 zeolite catalyst was developed for the reaction of methane with carbon monoxide to directly produce acetic acid under mild conditions (573-623 K), and two different intermediate-dependent reaction pathways were unambiguously identified for acetic acid formation by in situ solid-state NMR spectroscopy.
Tang Chu - - 2012
Five new conjugates of oleanolic acid derivatives and chalcones have been designed and synthesized. The structure elucidation of these conjugates was accomplished by using extensive 1D ((1) H, (13) C) and 2D NMR spectroscopic studies (COSY, HSQC and HMBC); and α-glucosidase inhibitory activity is reported for these conjugates. Compound 2b ...
Messaoudi Samir - - 2012
An efficient and practical decarboxylative cross-coupling reaction of quinolin-4(1H)-one 3-carboxylic acids with (hetero)aryl halides has been established. Under a bimetallic system of PdBr(2) and silver carbonate, the protocol proved to be general, and a variety of 3-(hetero)aryl 4-quinolinones and related heterocycles, such as 3-aryl-1,8-naphthyridin-4(1H)-ones, 3-arylcoumarins, 3-arylquinolin-2(1H)-ones, and 2-arylchromones, can be ...
O'Callahan D R - - 2012
Aims:  The aim of this study was to isolate lactic acid bacteria from chilli waste and evaluate metabolites produced for the ability to arrest wood decay. Methods and Results:  Using an optical density screening method, one bacterium (isolate C11) was identified as having pronounced antifungal properties against Oligoporus placenta. This ...
Wang Yao - - 2012
Chromatographic separation of a crude extract obtained from aerial parts of the Mongolian medicinal plant Scorzonera radiata yielded fifteen natural compounds, including two new flavonoids and one new quinic acid congener, as well as four flavones and eight quinic acid derivatives, all of which are known natural compounds. The structures ...
Li Ruixing - - 2012
Carbon and nitrogen (C-N) co-doped nano-CeO2 was synthesized by the solvothermal method using hexamethylenetetramine (HMT) as a precipitator at 140 degrees C for 24 h. We found that the degradation of acid orange 7 (AO7) was 94.4% and 98.8% with C-N co-doped nano-CeO2 upon irradiation with a 100-watt high-pressure mercury ...
Taskova Rilka M - - 2012
The sun hebes are a small clade of New Zealand Veronica formerly classified as Heliohebe. The water-soluble compounds of Veronica pentasepala, Veronica raoulii and Veronica hulkeana were studied and 30 compounds including 15 iridoid glucosides, 12 phenylethanoid glycosides, the acetophenone glucoside pungenin, the mannitol ester hebitol II and mannitol were ...
McGinty D - - 2012
A toxicologic and dermatologic review of benzyl acetate when used as a fragrance ingredient is presented. Benzyl 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 ...
Zeng Yan-Bo - - 2012
To study the antimicrobial components from the endophytic fungus A1 of mangrove plant Scyphiphora hydrophyllacea Gaertn. F., a new fatty acid glucoside was isolated by column chromatography from the broth of A1, and its structure was identified as R-3-hydroxyundecanoic acid methylester-3-O-α-l-rhamnopyranoside (1) by spectroscopic methods including 1D and 2D NMR ...
Hurtado Marcela - - 2012
The intrinsic acidity of chalcocyclopentadienes (CpXH; X=O, S, Se, Te) is investigated by high-level G3B3 and G2 ab initio as well as B3LYP DFT calculations, which show that, independent of the nature of the heteroatom, all chalcocyclopentadienes are stronger acids in the gas phase than cyclopentadiene. However the acidity does not increase regularly ...
Zhi Hai-Juan - - 2012
INTRODUCTION: The flower bud of Tussilago farfara L. is widely used for the treatment of coughs, bronchitis and asthmatic disorders in traditional Chinese medicine. In Europe, the plant has been used as herbal remedies for virtually the same applications, but the leaves are preferred over flowers. OBJECTIVE: To systematically evaluate ...
Domingues Adilson Pereira AP - - 2012
The aim of this study was to determine which anthocyanins are related to the purple colouration of young leaves in Coffea arabica var. Purpurascens and assess their impact on photosynthesis as compared to C. arabica var. Catuaí, with green leaves. Two delphinidin glicosides were identified and histological cross-sections showed they ...
Zaimoku Hisaaki - - 2012
A synthetic study of actinophyllic acid based on an original strategy has been described. A transannular acyl radical cyclization allowed us to obtain a key bicyclo[3.3.2] framework, and construction of a core of the target alkaloid has been accomplished by subsequent introduction of a C2 unit.
Flores-Albino Belem - - 2012
Crab wastes are employed for simultaneous production of chitin and L(+)-lactic acid by submerged fermentation of Lactobacillus sp. B2 using sugar cane molasses as carbon source. Response surface methodology was applied to design the culture media considering demineralization. Fermentations in stirred tank reactor (2L) using selected conditions produced 88% demineralization ...
Rohloff Jens - - 2012
Winter freezing damage is a crucial factor in overwintering crops such as the octoploid strawberry (Fragaria×ananassa Duch.) when grown in a perennial cultivation system. Our study aimed at assessing metabolic processes and regulatory mechanisms in the close-related diploid model woodland strawberry (Fragaria vescaL.) during a 10-days cold acclimation experiment. Based ...
Maresca Alfonso - - 2012
The bacterial pathogen Brucella suis encodes two carbonic anhydrases (CAs, EC 4.2.1.1) belonging to the β-class, bsCA1 and bsCA2, which are crucial for its life cycle. Sulfonamides, strong inhibitors of these enzymes, were shown to block the growth of the pathogen in vitro. Here we report the inhibition of these ...
Zhang Hua - - 2012
Fractionation of a southern Australian marine sponge, Ianthella sp., yielded sixteen metabolites including a new class of pyrrolidone, ianthellidones A-F (1-6), a new class of furanone, ianthellidones G-H (7-8), new and known lamellarins, lamellarins O1 (9), O2 (10), O (11) and Q (12), plus the known 4-hydroxybenzaldehyde (13), 4-hydroxybenzoic acid ...
López-Martínez Sugey - - 2012
Phoradendron brachystachyum is a hemiparasitic plant widely distributed in México that belongs to the Viscaceae family. It has been commonly used in folk medicine as a substitute for the European mistletoe. In this chemical study, morolic acid was isolated as the major component (47.54% of the total composition of acetone ...
Simo Mpetga James D - - 2012
Five new triterpenoids, caloncobic acids A and B (1 and 2), caloncobalactones A and B (3 and 4), and glaucalactone (5), along with the known compounds 3β,21β-dihydroxy-30-nor-(D:A)-friedo-olean-20(29)-en-27-oic acid (6) and acetyltrichadenic acid B (7), were isolated from the leaves of Caloncoba glauca. The structures of 1-5 were elucidated using spectroscopic ...
Gao Jian - - 2012
Convenient synthetic strategy toward spinasaponin A methyl ester 1 and calenduloside G methyl ester 2, two natural oleanane-type triterpenoid saponins bearing an unique β-d-glucosyl/galactosyl-(1→3)-β-d-glucuronic acid methyl ester disaccharide moiety, was established. Based on this facile approach, four structurally modified congeners 3-6 with ursolic acid and glycyrrhetinic acid as aglycones were ...
Rao Ramisetti Nageswara - - 2012
(R)-(-)-α-Methoxy phenyl acetic acid, (S)-(-)-1,1'-(2-naphthol), and (R)-(+)-α-methoxy-α-trifluoromethyl phenyl acetic acid were evaluated as chiral shift reagents (CSRs) for (1) H NMR spectroscopic resolution and determination of R and S enantiomers of modafinil (MDL) in bulk drugs and formulations. Effects of the nature of CSR and the weight ratio of substrate ...
Lubin Jean-Bernard - - 2012
Sialic or nonulosonic acids are nine-carbon alpha ketosugars that are present in all vertebrate mucous membranes. Among bacteria, the ability to catabolize sialic acid as a carbon source is present mainly in pathogenic and commensal species of animals. Previously, it was shown that several Vibrio species carry homologues of the ...
Lin Qiang - - 2012
This investigation examined the effects of the inorganic carbon concentration (4, 0.8 and 0g/L NaHCO(3)) on the carbon formation, nitrate utilization, growth and fatty acids compositions of Nannochloropsis oculata. The dissolved inorganic carbon (DIC) concentration in the three treatments decreased sharply during the first 6days, and the percentage of dissolved ...
Zhao Jin-Song - - 2012
The induced aggregation of achiral building blocks by a chiral species to form chiral aggregates with memorized chirality has been observed for a number of systems. However, chiral memory in isolated aggregates of achiral building blocks remains rare. One possible reason for this discrepancy could be that not much is ...
Aoki Nobuwa - - 2012
A new brominated C(17) acetylenic acid (1) designated as bromotheoynic acid has been isolated from the marine sponge Theonella swinhoei, collected off the coast of Tanegashima, Kagoshima Prefecture, Japan. The structure was determined on the basis of the analysis of its extensive 2D NMR spectroscopic data as well as HRMS. ...
Nahm Byung J - - 2012
A carbon dioxide laser operating at the highly absorbed wavelength of 9.3μm with a pulse duration of 10-15μs is ideally suited for caries removal and caries prevention. The enamel thermally modified by the laser has enhanced resistance to acid dissolution. This is an obvious advantage for caries prevention; however, it ...
Rudolf Christiane - - 2012
During fermentative metabolism, carbon dioxide fixation plays a key role in many bacteria regarding growth and production of organic acids. The present contribution, dealing with the facultative photosynthetic bacterium Rhodospirillum rubrum, reveals not only the strong influence of ambient carbon dioxide on the fermentative break-down of fructose but also a ...
Davalos Juan Zenon - - 2012
We have studied the energetics and structural properties of trans-cinnamic (CA), o-, m-, p-coumaric (2-, 3-, 4-hydroxycinnamic), caffeic (3,4-dihydroxycinnamic), ferulic (4-hydroxy-3-methoxycinnamic), iso-ferulic (3-hydroxy-4-methoxycinnamic) and sinapic (3,5-dimethoxy-4-hydroxycinnamic) acids. The experimental values of (g), determined (in kJ•mol-1) for CA (-229.8 ± 1.9), p-coumaric (-408.0 ± 4.4), caffeic (-580.0 ± 5.9) and ferulic ...
Schäfer André - - 2012
As you like it: The choice of solvents and substituents at the silicon atom determine what product is formed from carbon dioxide after electrophilic activation by silyl cations. Benzoic acid as well as the C-1 building blocks formic acid and methanol are on the product tableau.
Gómez Castaño Jovanny A - - 2012
The novel selenocarboxylic Se-acids, HCF(2)C(O)SeH and ClCF(2)C(O)SeH, were prepared by treating the corresponding carboxylic acids with Woollins' reagent. The boiling points were extrapolated from the vapor pressure curves to be 364 and 359 K for HCF(2)C(O)SeH and ClCF(2)C(O)SeH, respectively. Both compounds are unstable at ambient temperatures and decompose to the ...
Weylandt Karsten H - - 2012
Omega-3 polyunsaturated fatty acids (n-3 PUFAs) have long been associated with decreased inflammation and are also implicated in the prevention of tumorigenesis. Conventional thinking attributed this mainly to a suppressive effect of these fatty acids on the formation of arachidonic acid-derived prostaglandins and leukotrienes. Recent years have seen the discovery ...
Hadi Mojtaba - - 2012
Nanocrystalline graphite-like pyrolytic carbon film (PCF) electrode fabricated by a non-catalytic chemical vapor deposition (CVD) process was used for the simultaneous electrochemical sensing of ascorbic acid (AA), dopamine (DA), and uric acid (UA). The electrode was studied with respect to changes in electrocatalytic activity caused by a simple and fast ...
Kosová Klára - - 2012
Hormonal changes accompanying the cold stress (4°C) response that are related to the level of frost tolerance (FT; measured as LT50) and the content of the most abundant dehydrin, WCS120, were compared in the leaves and crowns of the winter wheat (Triticum aestivum L.) cv. Samanta and the spring wheat ...
Arslan-Alaton Idil - - 2012
The present paper deals with the effects of frequently used textile preparation chemicals and common ions on the H2O2/UV-C treatment of a commercially important and slowly biodegradable nonionic surfactant, namely a nonylphenol bearing 10 ethoxylated chains. For this purpose, the effect of soda ash carbonate (0-5.0 g L(-1)), two phosphonic ...
Hu Youcai - - 2012
A new peptide, L-O-Lac-L-Val-D-O-Hiv-D-Val (1), consisting of D-valine, L-valine, L-lactic acid, and 3-D-hydroxyisovaleric acid, was isolated from the culture of the marine sediment derived Streptomyces bacillaris. The planar structure of compound 1 was assigned by 1D, 2D NMR and mass spectroscopic analyses. Following acid and base hydrolysis, the absolute configuration ...
Tao Si-Jia - - 2012
Microbial transformation of gambogenic acid (1), a caged polyprenylated xanthone isolated from the resin of Garcinia hanburyi, was carried out with Chaetomium globosum CICC 2445, after screening forty-six strains of filamentous fungi. A new caged polyprenylated xanthone, 16,17-dihydroxygambogenic acid (2), was specifically obtained, as a result of hydroxylation at C-16, ...
Felchner-Zwirello Monika - - 2012
Biowaste digestion is a possibility to gain biogas as a renewable fuel source. However, the anaerobic food chain may be disrupted by, e.g., substrate overload or by inhibitors, leading to the accumulation of volatile fatty acids (VFAs), predominantly of propanoic acid (PA). VFA Accumulation may cause a rapid pH decrease, ...
Badrinarayanan Sandhya - - 2012
The dimerization of amino acid-derived α-amino aldehydes provides a short, biomimetic synthesis of several 2,5-disubstituted pyrazine natural products. The α-amino aldehyde intermediates were generated in situ by the hydrogenolysis of their Cbz-derivatives. It was found that a judicious choice of reaction solvent facilitated hydrogenolysis, dimerization and oxidation to the natural ...
Stierle Andrea A - - 2012
Berkeley Pit Lake, Butte, Montana, is a 540 m deep abandoned open-pit copper mine filled with over 140 billion liters of acidic, metal-sulfate-contaminated water. This harsh environment has yielded several microorganisms that produce interesting biologically active compounds. Several polyketide metabolites including the new berkazaphilones A (1) and B (2) and ...
Clark Valerie C - - 2012
The skins of Madagascar poison frogs (Mantella) and certain Neotropical poison frogs (Epipedobates, Dendrobates) secrete the new bile acid tauromantellic acid (1), which was found in both wild-caught and captive-born frogs. This is the first molecule of endogenous origin detected in skin secretions from these taxa. Sucrose was also detected ...
Li Ming-Fei - - 2012
Fractionation of lignocellulosic material into its constitutive components is of vital importance for the production of biofuels as well as other value-added chemicals. The conventional acetosolv processes are mainly focused on the production of pulp from woody lignocelluloses. In this study, a mild acetosolv process was developed to fractionate bamboo ...
Zhou Zhong-Yu - - 2012
Life saver: Two unusual and toxic amino acids, 2R-amino-4S-hydroxy-5-hexynoic acid (red, see scheme) and 2R-amino-5-hexynoic acid (blue) have been isolated from the fruiting bodies of the mushroom Trogia venenata. Toxicology studies suggest that these compounds may be the cause of Sudden Unexplained Death (SUD) in Yunnan Province, China.
Vysotsky Yuri B - - 2012
In the frameworks of the quantum-chemical semiempirical PM3 method, the thermodynamic parameters of trans-isomers of unsaturated carboxylic acids at the air/water interface were studied. Systems with 18-26 carbon atoms in the alkyl chain and different positions of the double bond are considered. Using quantum-chemical semiempirical PM3 method enthalpy, Gibbs' energy ...
< 3 4 5 6 7 8 9 10 11 12 13 >