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Phosphates diamines

Triethylene diamine (TEDA), 230, 231 Triethyl phosphate (TEP), 354 Trifluoroactic anhydride, 78 Trifhioromethanesulfonic acid, 334 Trifunctional monomers, 14 Triglyceride content, in resins, 60 Trihydroxymethylphenol curing process, 410... [Pg.603]

Stabilisers are usually determined by a time-consuming extraction from the polymer, followed by an IR or UV spectrophotometric measurement on the extract. Most stabilisers are complex aromatic compounds which exhibit intense UV absorption and therefore should show luminescence in many cases. The fluorescence emission spectra of Irgafos 168 and its phosphate degradation product, recorded in hexane at an excitation wavelength of 270 nm, are not spectrally distinct. However, the fluorescence quantum yield of the phosphate greatly exceeds that of the phosphite and this difference may enable quantitation of the phosphate concentration [150]. The application of emission spectroscopy to additive analysis was illustrated for Nonox Cl (/V./V -di-/i-naphthyl-p-phcnylene-diamine) [149] with fluorescence ex/em peaks at 392/490 nm and phosphorescence ex/em at 382/516 nm. Parker and Barnes [151] have reported the use of fluorescence for the determination of V-phenyl-l-naphthylamine and N-phenyl-2-naphthylamine in extracted vulcanised rubber. While pine tar and other additives in the rubber seriously interfered with the absorption spectrophotometric method this was not the case with the fluoromet-ric method. [Pg.322]

Urethane hydrolyzes into an amine, an alcohol, and carbon dioxide. So the possible degradation products of a poly(phosphoester-urethane) are diamines, diols, phosphates, carbon dioxide, and even ureas. Urea is possible because the isocyanate is extremely sensitive to moisture, which would convert the isocyanate to an amino group. One is therefore bound to have traces of diamine in the polymerization that leads to a urea bond in the backbone. We think the cytotoxicity seen in the macrophage functional assay comes from the TDI structure. [Pg.152]

Buffer and chemicals pH 7.8 phosphate buffer (16.29g Na2HP04-2H20, 1.17g NaH2P04H20, 1000 ml distilled water), Ethylene Diamine Tetra Acetic Acid (EDTA), Methionine (Met), Polyvinylpyrrolidone (PVP), Triton X-100, Phenylmethylsulphonylfluoride (PMSF), Riboflavin, Nitro Blue Tetrazolium (NBT). [Pg.169]

Figure 1.97 Phosphate groups may be modified to possess amines by a carbodiimide reaction in the presence of a diamine. Figure 1.97 Phosphate groups may be modified to possess amines by a carbodiimide reaction in the presence of a diamine.
To make an amine derivative of dextran, dissolve ethylene diamine (or another suitable diamine) in 0.1 M sodium phosphate, 0.15 M NaCl, pH 7.2, at a concentration of 3 M. Note Use of the hydrochloride form of ethylene diamine is more convenient, since it avoids having to adjust the pH of the highly alkaline free-base form of the molecule. Alternatively, to prepare a hydrazide-dextran derivative, dissolve adipic acid dihydrazide (Chapter 4, Section 8.1) in the coupling buffer at a concentration of 30 mg/ml (heating under a hot water tap may be necessary to completely dissolve the hydrazide compound). Adjust the pH to 7.2 with HC1 and cool to room temperature. [Pg.956]

Figure 27.5 Oligonucleotides containing a 5 -phosphate group can be reacted with EDC in the presence of imidazole to form an active phosphorimidazolide intermediate. This derivative is highly reactive with amine nucleophiles, forming a phosphoramidate linkage. Diamines reacted with the phosphorimidazolide result in amine-terminal spacers that can be modified with detectable components. Figure 27.5 Oligonucleotides containing a 5 -phosphate group can be reacted with EDC in the presence of imidazole to form an active phosphorimidazolide intermediate. This derivative is highly reactive with amine nucleophiles, forming a phosphoramidate linkage. Diamines reacted with the phosphorimidazolide result in amine-terminal spacers that can be modified with detectable components.
The following protocol describes the modification of DNA or RNA probes at their 5 -phosphate ends with a bis-hydrazide compound, such as adipic acid dihydrazide or carbohydrazide. A similar procedure for coupling the diamine compound cystamine can be found in Section 2.2 (this chapter). [Pg.980]

Figure 27.7 A oligonucleotide modified at its 5 -phosphate with a diamine compound may be reacted with SPDP and subsequently reduced to create a free sulfhydryl. Figure 27.7 A oligonucleotide modified at its 5 -phosphate with a diamine compound may be reacted with SPDP and subsequently reduced to create a free sulfhydryl.
Figure 27.10 Biotinylation of oligonucleotides may be done at the 5 -phosphate end using a diamine derivative and reacting with NHS-LC-biotin. Figure 27.10 Biotinylation of oligonucleotides may be done at the 5 -phosphate end using a diamine derivative and reacting with NHS-LC-biotin.
Fig. 3.154. Electropherogram for the working solution of aromatic amines. Peaks 1 = 4,4 -diamin-odiphenylmethane 2 = 4,4 -oxidianiline 3 = benzidine 4 = aniline 5 = 2,4-diaminoanisole 6 = 2,4 -toluilendiamine 7 = o-toluidine 8 = 3,3 -dimethylbenzidine 9 = 3,3 -dimethoxyben-zidine 10 = p-cresidine 11 = 2-naphtylamine 12 = p-chloroaniline 13 = 4-aminodiphenyl 14 = 1-naphtylamine 15 = 4-chlorotoluidine all at 10 ng/jul. Conditions buffer = 50 mM phosphate 10 per cent methanol pH = 3.1 fused-silica capillary recovered with polyamide, 52 cm X 75 pm i.d. applied potential = +22 kV UV detection at 214 nm. Reprinted with permission from S. Borros et al. [195]. Fig. 3.154. Electropherogram for the working solution of aromatic amines. Peaks 1 = 4,4 -diamin-odiphenylmethane 2 = 4,4 -oxidianiline 3 = benzidine 4 = aniline 5 = 2,4-diaminoanisole 6 = 2,4 -toluilendiamine 7 = o-toluidine 8 = 3,3 -dimethylbenzidine 9 = 3,3 -dimethoxyben-zidine 10 = p-cresidine 11 = 2-naphtylamine 12 = p-chloroaniline 13 = 4-aminodiphenyl 14 = 1-naphtylamine 15 = 4-chlorotoluidine all at 10 ng/jul. Conditions buffer = 50 mM phosphate 10 per cent methanol pH = 3.1 fused-silica capillary recovered with polyamide, 52 cm X 75 pm i.d. applied potential = +22 kV UV detection at 214 nm. Reprinted with permission from S. Borros et al. [195].
A series of diaquatetraaza cobalt(III) complexes accelerated the hydrolysis of adenylyl(3 -50adenosine (ApA) (304), an enhancement of 10 -fold being observed with the triethylenetetramine complex (303) at pH 7. The pentacoordinated intermediate (305), which is formed with the complex initially acting as an electrophilic catalyst, then suffers general acid catalysis by the coordination water on the Co(III) ion to yield the complexed 1,2-cyclic phosphate (306), the hydrolysis of which occurs via intracomplex nucleophilic attack by the metal-bound hydroxide ion on the phosphorus atom. Neomycin B (307) has also been shown to accelerate the phosphodiester hydrolysis of ApA (304) more effectively than a simple unstructured diamine. [Pg.91]

Among the chemicals which have been shown to be mutagens in Salmonella (as well as other short-term tests) that have recently been shown to be carcinogens are 1,2-dichloroethane (10 x 109 Ibs/year, U.S.), tris-dibromopropyl phosphate (the flame retardant used in children s polyester sleepwear), sulfallate (a pesticide), o-phenylene-diamine, 2,4-diaminoanisole (hair dye ingredient), 2-nitro-p-phenylenediamine (hair dye ingredient), and 4-amino-2-nitro-phenol (hair dye ingredient). [Pg.6]

The synthesis pathway of quinolizidine alkaloids is based on lysine conversion by enzymatic activity to cadaverine in exactly the same way as in the case of piperidine alkaloids. Certainly, in the relatively rich literature which attempts to explain quinolizidine alkaloid synthesis °, there are different experimental variants of this conversion. According to new experimental data, the conversion is achieved by coenzyme PLP (pyridoxal phosphate) activity, when the lysine is CO2 reduced. From cadeverine, via the activity of the diamine oxidase, Schiff base formation and four minor reactions (Aldol-type reaction, hydrolysis of imine to aldehyde/amine, oxidative reaction and again Schiff base formation), the pathway is divided into two directions. The subway synthesizes (—)-lupinine by two reductive steps, and the main synthesis stream goes via the Schiff base formation and coupling to the compound substrate, from which again the synthetic pathway divides to form (+)-lupanine synthesis and (—)-sparteine synthesis. From (—)-sparteine, the route by conversion to (+)-cytisine synthesis is open (Figure 51). Cytisine is an alkaloid with the pyridone nucleus. [Pg.89]

Complexes with organic compounds have been reported. Solubility studies with tributyl phosphate (TBP) indicate the formation of a complex PoC14-2TBP (IS). Weighable amounts of polonium tetrachloride in dilute hydrochloric acid can be titrated to a colorless end point with ethylene-diamine tetra-acetic acid (EDTA) the results suggest a complex with two molecules of EDTA, but solubility studies favor a 1 1 complex. The EDTA complex is soluble in alkali and is more stable in alkaline than in acid media, but the ligand is rapidly destroyed by the radiation and solvent radiolysis products 12). However, EDTA can apparently be used to complex trace polonium in the separation of radium D-E-F mixtures (129). [Pg.215]

To determine the nature of the catalysis of salicyl phosphate hydrolysis by metal chelates, two diamine-Cu(II) chelates were selected for detailed study, N-/ -hydroxyethylethylenediamine-Cu(II) ion (XXV) and a,a -bipyridine-Cu(II) ion (XXVI) (II). [Pg.172]


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See also in sourсe #XX -- [ Pg.124 ]




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Phosphate groups diamines

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