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Ethanolamine activation

An ammoniacal solution is added just before use to activate the hydrogen peroxide. Ammonia is preferred over sodium carbonate (40) or ethanolamines for maximum bleaching. The alkaline solution can be formulated iato a shampoo vehicle with oleate soaps or ethoxylated fatty alcohols. When the bleach is appHed to areas such as new hair growth, a viscous cream or paste may be preferred, formulated with fatty alcohols, alkanolamides, or other thickeners. [Pg.458]

Giclopiroxolamine. This ethanolamine salt, C24H24N2O2, of ciclopinox (9) is a topically active antimycotic, available as a cream and powder... [Pg.254]

SolubiHty of carbon dioxide in ethanolamines is affected by temperature, amine solution strength, and carbon dioxide partial pressure. Information on the performance of amines is available in the Hterature and from amine manufacturers. Values for the solubiHty of carbon dioxide and hydrogen sulfide mixtures in monoethanolamine and for the solubiHty of carbon dioxide in diethanolamine are given (36,37). SolubiHty of carbon dioxide in monoethanolamine is provided (38). The effects of catalysts have been studied to improve the activity of amines and provide absorption data for carbon dioxide in both mono- and diethanolamine solutions with and without sodium arsenite as a catalyst (39). Absorption kinetics over a range of contact times for carbon dioxide in monoethanolamine have also been investigated (40). [Pg.22]

High yields of optically active cyanohydrins have been prepared from hydrogen cyanide and carbonyl compounds using an enzyme as catalyst. Reduction of these optically active cyanohydrins with lithium aluminum hydride in ether affords the corresponding substituted, optically active ethanolamine (5) (see Alkanolamines). [Pg.411]

It was therefore of some interest to so modify the molecule as to maximize this particular activity at the expense of the side effects. In much the same vein as the work on cocaine, the structural requirements for the desired activity had at one time been whittled down to embrace in essence an a-substituted phenylacetic acid ester of ethanolamine (S3). [Pg.35]

Antispasmodic activity, interestingly, is maintained even in the face of the deletion of the ethanolamine ester side chain. Reaction of anisaldehyde with potassium cyanide and dibutylamine hydrochloride affords the corresponding a-aminonitrile (72) (a functionality analogous to a cyanohydrin). Treatment with sulfuric acid hydrolyzes the nitrile to the amide to yield ambucet-amide (73). ... [Pg.94]

It has by now been reasonably well established that an ethanolamine function appropriately linked to an aromatic ring is a prerequisite for beta adrenergic activity and/or antagonism. Examples have been met above where those two moieties are attached directly as well as examples where the funetions are separated by an oxymethylene fragment. It has reeently been found that beta blocking activity is retained even when a earbonyl is inserted between the extra oxymethylene... [Pg.40]

Properties of PS-A and PS-B (Shimomura, 1991b Shimomura et al., 1993b). Both PS-A and PS-B are colorless viscous liquid, and their absorption spectra resemble that of panal (Fig. 9.6). By NMR analysis and mass spectrometry, PS-A and PS-B are found to be 1-O-decanoylpanal and 1-O-dodecanoylpanal, respectively. As a minor component, 1-O-tetradecanoylpanal has also been isolated. PS-A and PS-B gain chemiluminescence activity when treated with the salt of primary amines (see below for the conditions). Taking the activity obtained with methylamine as 100%, the activities obtained with other amines were ethylamine, 38% ethanolamine, 10% propylamine, 20% hexylamine, 3% and decylamine, 1%. [Pg.283]

Porous glass (PG) modified with covalently adsorbed poly(p-nitrophenyl acrylate), as described in Sect. 4.1, turned out to be a highly suitable carrier for immobilization of various biospecific ligands and enzymes. When the residual active ester groups of the carrier were blocked by ethanolamine, the immobilized ligands when bound to the solid support via hydrophilic and flexible poly(2-hydroxyethyl acrylamide). The effective biospecific binding provided by the ligands... [Pg.170]

Recently, an environmentally benign and volume efficient process for enzymatic production of alkanolamides has been described where CALB catalyzes the amidation of lauric acid and ethanolamine in the absence of solvent, at 90 °C, to keep the reactants in a liquid state and to remove the water [18]. The enzyme was both very active and stable under the reaction conditions, with about half of the activity remaining after two weeks, obtaining the final amide with a 95% yield (Scheme 7.6). [Pg.175]

PGIP, purified fi om P.vulgaris hypocotyls [11], was immobilized to the sensor ch via amine coupling. A continuous flow of HBS buffer (5 pl/min) was mantained over the sensor surface. The carboxylated dextran matrix of the sensor surface was first activated by a 6-min injection of a mixture of N-hydroxy-succinimide and N-ethyl-N - (3-diethylaminopropyl) carbodiimide, followed by a 7-min injection of PGIP (lOng/pl in 10 mM acetate, pH 5.0). Hie immobilization procedure was con leted by a 7-min injection of 1 M ethanolamine hydrochloride to block the remaining ester groups. [Pg.776]

The synthesis of ethylenediamine (EDA) from ethanolamine (EA) with ammonia over acidic t3pes of zeolite catalyst was investigated. Among the zeolites tested in this study, the protonic form of mordenite catalyst that was treated with EDTA (H-EDTA-MOR) showed the highest activity and selectivity for the formation of EA at 603 K, W/F=200 g h mol, and NH3/ =50. The reaction proved to be highly selective for EA over H-EDTA-MOR, with small amounts of ethyleneimine (El) and piperazine (PA) derivatives as the side products. IR spectroscopic data provide evidence that the protonated El is the chemical intermediate for the reaction. The reaction for Uie formation of EDA from EA and ammonia required stronger acidic sites in the mordenite channels for hi er yield and selectivity. [Pg.267]

An important feature of the antibiotic chloramphenicol (9) is the presence of the dichloroacetamide function. Inclusion of this amide in a simpler molecule, teclozan (15), leads to a compound with antiamebic activity. Whether this is cause and effect or fortuitous is unclear. The synthesis begins with alkylation of the alkoxide derived from ethanolamine (10) with ethyl iodide to give the aminoether (11). Reaction of a,a -dibromo-p-xylene (12) with 2-nitropropane in the presence of base leads to dialdehyde (13). The reaction probably proceeds by O-alkylation on the nitropropyl anion... [Pg.28]

As noted above, phenylethanolamines are usually p-adrenergic agonists, whereas phenylpropanolamines show antagonist activity. A small series of phenyl-ethanolamine blockers is, however, known. When the haloatom of u)-bromo-5,6,7,8-tetrahydro-2-acetonaphth-one (36) is displaced with isopropylamine and the... [Pg.214]

Spin labeled 5 -deoxyadenosylcobinamide has been used as a cofactor for ethanolamine-ammonia-lyase and the ESR spectrum followed during catalysis (123). This spin labeled coenzyme is biologically active in this enzyme. Enzyme kinetics showed this derivative to have the same Vmax as the cofactor 5 -deoxyadenosylcobinamide, but it has a higher Km value of 5.1 X 10-6 M compared to 4.6 X 10-6 for 5 -deoxyadenosylcobinamide (123). When the spin labeled coenzyme was incubated with apoenzyme to give the enzyme-coenzyme complex, the nitroxide ESR spectrum resembled that of free spin label but the lines are broadened significantly. [Pg.82]

The oxidative dehydrogenation of ethanolamine to sodium glycinate in 6.2 M NaOH was investigated using unpromoted and chromia promoted skeletal copper catalysts at 433 K and 0.9 MPa. The reaction was first order in ethanolamine concentration and was independent of caustic concentration, stirrer speed and particle size. Unpromoted skeletal copper lost surface area and activity with repeated cycles but a small amount of chromia (ca. 0.4 wt%) resulted in enhanced activity and stability. [Pg.27]

Chitwood (2) found that copper compounds exhibited only a short period of maximum catalytic activity for the dehydrogenation of ethanolamine to glycine salt. In this study, the catalytic activity of a skeletal copper catalyst was tested in repeated use. The catalyst used was prepared by selectively leaching CuAl2 particles in a 6.1 M NaOH solution at 293 K for 24 hours. Figure 1 shows the profiles of hydrogen evolved versus reaction time. [Pg.28]

The oxidative dehydrogenation of ethanolamine over skeletal copper catalysts at temperatures, pressures and catalyst concentrations that are used in industrial processes has been shown to be independent of the agitation rate and catalyst particle size over a range of conditions. A small content of chromia (ca. 0.7 wt %) provided some improvement to catalyst activity and whereas larger amounts provided stability at the expense of activity. [Pg.34]

PS-b-PEO) , n = 3, 4 star-block copolymers were synthesized by ATRP and anionic polymerization techniques [149]. Three- or four-arm PS stars were prepared using tri- or tetrafunctional benzylbromide initiators in the presence of CuBr/bipy. The polymerization was conducted in bulk at 110 °C. The end bromine groups were reacted with ethanolamine in order to generate the PS stars with hydroxyl end groups. These functions were then activated by DPMK to promote the polymerization of ethylene oxide and afford the desired well-defined products (Scheme 73). [Pg.85]

ELECTROCHEMICAL ACTIVITY OF CARBONS MODIFIED BY d-METAL COMPLEXES WITH ETHANOLAMINES... [Pg.345]

Modification of carbon materials by tri-nuclear complexes of 3d-metals with ethanolamine ligands increases the catalytic activity with regard to the electrochemical reaction of oxygen reduction. The Co-Ni complex is most active in this reaction if pyrolyzed at 600°C. [Pg.355]

Add ethanolamine to the particle suspension at a final concentration of 0.1 M to quench any remaining active groups and react with mixing for several hours. [Pg.610]

Add ethanolamine to the particle suspension at a final concentration of 0.1 M to quench any remaining active groups and react with mixing for 1 hour. Other amine-containing quenchers may be used, too, such as Tris buffer. Note DSC-activated sites on the particles that completely hydrolyze will revert back to the original hydroxyls. [Pg.611]

Note Some protocols do not call for a reduction step. The addition of borohydride at this level may result in disulfide bond cleavage and loss of protein activity in some cases. As an alternative to reduction, add 50pi of 0.2M lysine in 0.5M sodium carbonate, pH 9.5 to each ml of the conjugation reaction to block excess reactive sites. Block for 2 hours at room temperature. Other amine-containing small molecules may be substituted for lysine—such as glycine, Tris buffer, or ethanolamine. [Pg.913]

This process probably occurs in vivo because the adduct of ethanolamine and p-hydroxyphe-nylacetaldehyde is abundant in the phospholipids of LDL exposed to activated neutrophils and tyrosine. [Pg.796]


See other pages where Ethanolamine activation is mentioned: [Pg.137]    [Pg.107]    [Pg.137]    [Pg.107]    [Pg.250]    [Pg.299]    [Pg.44]    [Pg.72]    [Pg.465]    [Pg.52]    [Pg.199]    [Pg.203]    [Pg.81]    [Pg.71]    [Pg.213]    [Pg.363]    [Pg.81]    [Pg.27]    [Pg.28]    [Pg.31]    [Pg.31]    [Pg.61]    [Pg.120]    [Pg.396]    [Pg.133]    [Pg.167]    [Pg.49]   
See also in sourсe #XX -- [ Pg.230 ]




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Ethanolamines

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