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Utilization of formaldehyde

Sutherland BW, Toews J, Kast J. Utility of formaldehyde cross-linking and mass spectrometry in the study of protein-protein interactions. J. Mass. Spectrom. 2008 43 699-715. [Pg.367]

More recently it has been observed that 2-amino-4-hydroxy-6,7-dimethyltetra-hydropteridine, which lacks N °, is unable to substitute for FH as a coenzyme in the utilization of formaldehyde for the enzymic formation of serine and of thymine-methyl (48a). The corresponding dimethyldihydropteridine can serve as a substrate for dihydrofolic acid reductase. [Pg.180]

The potential utility of formaldehyde predissociation for isotope separation was pointed out independently by Yeung and Moore and Letokhov in 1972. Yeung and Moore recognized that there were predisso-ciative channels to both molecular and radical products. [Pg.5]

Urea is also used as feed supplement for mminants, where it assists in the utilization of protein. Urea is one of the raw materials for urea—formaldehyde resins. Urea (with ammonia) pyrolyzes at high temperature and pressure to form melamine plastics (see also Cyanamides). Urea is used in the preparation of lysine, an amino acid widely used in poultry feed (see Amino acids Feeds and feed additives, petfoods). It also is used in some pesticides. [Pg.310]

The reaction of methyl propionate and formaldehyde in the gas phase proceeds with reasonable selectivity to MMA and MAA (ca 90%), but with conversions of only 30%. A variety of catalysts such as V—Sb on siUca-alumina (109), P—Zr, Al, boron oxide (110), and supported Fe—P (111) have been used. Methjial (dimethoxymethane) or methanol itself may be used in place of formaldehyde and often result in improved yields. Methyl propionate may be prepared in excellent yield by the reaction of ethylene and carbon monoxide in methanol over a mthenium acetylacetonate catalyst or by utilizing a palladium—phosphine ligand catalyst (112,113). [Pg.253]

Other. 2-Nitro-1-butanol is an excellent solvent for many polyamide resins, cellulose acetate butyrate, and ethylceUulose. It can be utilized in paint removers for epoxy-based coatings. 2-Hydroxymethyl-2-nitro-l,3-propanediol is usebil for control of odors in chemical toilets. Its slow release of formaldehyde ensures prolonged action to control odor, and there is no reodorant problem which sometimes is associated with the use of free formaldehyde. 2-Hydroxymethyl-2-nitro-l,3-propanediol solutions are effective preservative and embalming fluids. The slow Uberation of formaldehyde permits thorough penetration of the tissues before hardening. [Pg.62]

Early Gross-Linking Agents. Eormaldehyde, urea—formaldehyde, and melamine—formaldehyde were among the eadiest agents utilized for resin finishes. Concerns about the safety of formaldehyde, the need for lower formaldehyde release values, and the safety of exposure to melamine have reduced the use of these early cross-linking agents by industry substantially. [Pg.443]

Older cook styles called for addition of phenol, formaldehyde, and water followed by alkali. Once the alkali was added, strict temperature control was the only barrier to a runaway reaction. A power or equipment failure at this point was likely to lead to disaster. Every batch made involved a struggle between the skill of the operator and capability of the equipment to control the exotherm versus the exothermic nature of the reactants. Most of the disasters that have occurred were due to utilization of this cooking method. [Pg.885]

Aliphatic and aromatic aldehydes condensed with 2-amino-(62BRP898414), 5-amino- (80AJC1147), or 8-amino-l,2,4-triazolo[l,5-cjpyrimidines (68JOC530) to give the related Schiff bases. Treatment of the 2-amino-5-methyl-l,2,4-triazolo[l,5-c]quinazoline 11 with formaldehyde and piperidine in the presence of acetic acid gave the 2-hydroxymethyl-amino-5-(2-piperidinoethyl) derivative 172. Utilization of aromatic aldehydes and piperidine in this reaction gave the 2-arylideneamino-5-styryl derivatives 173 (68CB2106) (Scheme 67). [Pg.377]

The testing of impnrities in active pharmacentical ingredients has become an important initiative on the part of both federal and private organizations. Franolic and coworkers [113] describe the utilization of PLC (stationary phase — silica gel and mobile phase — dichloromethane-acetonitrile-acetone (4 1 1, v/v)) for the isolation and characterization of impurities in hydrochlorothiazide (diuretic drug). This drug is utilized individually or in combination with other dmgs for the treatment of hypertension. The unknown impurity band was scraped off the plate and extracted in acetonitrile. The solution was filtered and used for LC/MS and NMR analysis. The proposed procedure enabled the identification of a new, previonsly nnknown impurity. It was characterized as a 2 1 hydrochlorothiazide-formaldehyde adduct of the parent drug substance. [Pg.227]

Recently, Vasilescu et al. demonstrated the use of formaldehyde to preserve protein interactions in vivo followed by immunoaffinity purification of a targeted complex, cross-link reversal via heating at 95°C, separation by SDS-PAGE, and identification of bands by LC-MS/MS.7 Tagwerker et al. utilized formaldehyde cross-linking in conjunction with a novel tag-based affinity purification method.36... [Pg.362]

Recently, the enzymatic formation of folinic acid has been utilized to synthesize radioactively labeled products.34 The preparation of 5-formyl tetrahydrofolate, 9,3, 5 -3H and 5-formyl-14C-tetrahydrofolate starts with tritiated folic acid, which is reduced to dihydrofolate, incubated in the presence of formaldehyde, dihydrofolate reductase, and NADPH, and finally incubated with 5,10-methylenetetrahydrofolate dihydrogenase. The product,... [Pg.331]

Though much effort has been spent on possible utilization of poly(thio-formaldehyde), no uses for the polymer have been developed. Most samples of the polymer cannot be melt fabricated because they are unstable in the molten state. Solvent fabrication is also impossible because the polymer is insoluble. There are two types erf poly(thioformaldehyde) that are said to be stable at high temperatures, which are polymers made by treatment of trithiane with boron trifluoride etherate and the acetylated anomalous form obtained from sodium hydrosulfide and methylene chloride. These also have not found utility. [Pg.80]

Its toxicity is discussed by Curme Johnston (Ref 4, p 317). In skin absorption it is about l/l0th as toxic as formaldehyde The industrial utilization of glyoxal is largely based on the advantage which may be taken of its two aldehyde groups, its lack of volatility from aqueous solns, and its inoffensive color. Among its uses may be cited in-solubilizing of proteins, polyvinyl, alcohol, starch, etc (Ref 4, p 127) (See also Ref 5). [Pg.760]

Effect of pH on the yield of formaldehyde (triangle) and nitrogen dioxide (diamond) produced from peroxynitrous acid attack upon 100 mM DMSO. All reactions were conducted at 37°C in 50 mM potassium phosphate buffer. The pH was measured after the addition of peroxynitrite to account for the alkaline peroxynitrite addition. Peroxynitrite did not attack 24 /iM formaldehyde (circle) under the reactions conditions utilized. [Pg.51]


See other pages where Utilization of formaldehyde is mentioned: [Pg.230]    [Pg.276]    [Pg.277]    [Pg.331]    [Pg.418]    [Pg.360]    [Pg.362]    [Pg.230]    [Pg.276]    [Pg.277]    [Pg.331]    [Pg.418]    [Pg.360]    [Pg.362]    [Pg.102]    [Pg.493]    [Pg.886]    [Pg.223]    [Pg.357]    [Pg.1038]    [Pg.201]    [Pg.33]    [Pg.236]    [Pg.343]    [Pg.182]    [Pg.69]    [Pg.69]    [Pg.391]    [Pg.554]    [Pg.654]    [Pg.437]    [Pg.228]    [Pg.169]    [Pg.50]    [Pg.102]    [Pg.322]    [Pg.96]    [Pg.277]   
See also in sourсe #XX -- [ Pg.276 ]

See also in sourсe #XX -- [ Pg.276 ]




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Formaldehyde utilization

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