Chemical structures amines

Chemical Structure. Amine-cured epoxy networks generally form exclusively from epoxide-amine addition reactions i.e.. 

To avoid these problems, refiners commonly use additives called detergents" (Hall et al., 1976), (Bert et al., 1983). These are in reality surfactants made from molecules having hydrocarbon chains long enough to ensure their solubility in the fuel and a polar group that enables them to be absorbed on the walls and prevent deposits from sticking. The most effective chemical structures are succinimides, imides, and fatty acid amines. The required dosages are between 500 and 1000 ppm of active material. 

Molecular structural analysis is a developing method. The objective of a molecuhu structural analysis is to demonstrate a physical, structural, or chemical similarity between tlie chemical in question and a known toxic chemical tliat produces toxic and healtli effects in experimental animals and/or humans. Unfortunately, scientists do not fully understand tlie effects of slight changes in tlie chemical structure and tlieir biological effect on humans. As a result, tills type of analysis is useful in preliminary studies to identify potential health hazards for further e. amination with more established metliods in short-tenii tests or tests in experimental animals, hi its present stage of development, molecular structural analysis caiuiot be used to make absolute decisions about tlie appropriate levels of exposure of humans to chemicals... 

Kami H, T Watanabe, S Takemura, Y Kameda, T Hirayama (2000) isolation and chemical-structural identification of a novel aromatic amine mutagen in an ozonized solution of m-phenylenediamine. Chem Res Toxicol 13 165-169. 

Histamine is a mediator of several physiological and pathological processes within and outside the nervous system 249 The chemical structure of histamine has similarities to the structure of other biogenic amines, but important differences also exist 250... 

The chemical structure of histamine has similarities to the structures of other biogenic amines, but important differences also exist. Chemically, histamine is 2-(4-imidazolyl)ethylamine (Fig. 14-1). The ethylamine backbone is a common feature of many of the amine transmitters (e.g. dopamine, norepinephrine and serotonin). However, the imidazole nucleus, absent from other known transmitters, endows histamine with several distinct chemical properties. Among these is prototypic tautomerism, a property that permits it to exist in two different chemical forms (Fig. 14-1). The tautomeric properties of histamine are thought to be critical in the... 

SCHEME 3.58 Chemical structure of triarylbenzene host and DSA-amine guest. 

SCHEME 3.69 Chemical structures of aromatic amines blue emitters as well as hosts. 

In the Colour Index both conventional sulphur dyes and their leuco counterparts are allocated the same Cl constitution number a different number is given to the related solubilised version. Thus, for example, Cl Sulphur Black 1 and Cl Leuco Sulphur Black 1 have the reference Cl 53185 whereas Cl Solubilised Sulphur Black 1 appears under Cl 53186. Because of the complexity of the final products, sulphur dyes are classified according to the chemical structure of the organic starting material that predominates in the manufacturing process. Typical intermediates include aromatic amines, with or without nitro and phenolic groups, and diphenylamine derivatives. 

Only common aromatic amines are used as diazonium components. Coupling reactions between aminobenzamides or aminobenzanilides and bisacetoacetylamino-phenylenes are described under disazo condensation pigments (see Sec. 2.9). Bisacetoacetarylide pigments thus have the general chemical structure ... 

Fig. 2.12.1. Chemical structure of different classes of cationic surfactants (a) quaternary ammonium surfactants (quats) (b) dialkylcarboxyethyl hydroxyethyl methyl ammonium surfactants (esterquats) (c) alkyl polyglycol amine surfactants (d) quaternary perfluoro-alkyl ammonium surfactants (e) N, N, N1, JV -tetramethyl-iV, iV -didodecyle-l,3-propane-diyle-diammonium dibromide (cationic gemini surfactant). R = alkyl or benzyl group.

In fact, it has been previously observed that measured diameters of dendrimer molecules by AFM are much larger than the theoretical values, which indicates that the dendrimers spread out and flatten on the surface [25, 26], Three major factors could account for this deformation. First, the unique architecture and chemical structure of PAMAM dendrimers result in macromolecules that are not solid balls, but instead are relatively open and hence soft materials. It is expected that the rigidity will increase substantially with increasing generation number [9]. Therefore, when deposited on solid substrates, they tend to deform to different degrees as a result of the interplay between their inherent rigidity and surface energetics from the interaction between the dendrimer molecules and the mica surface. Secondly, amine-terminated PAMAM dendrimers possess a... 

Organic dye nanoparticles of DHIA and DHBIA (the chemical structures are shown in Fig. 1) have been synthesized in THF/water mixed solvent by a reprecipitation method [32]. These dye molecules possess a 2-(2-hydroxyphenyl) benzothiazole (HBT) unit, which is known to be more stable as an enol imine form in the ground state and as a keto amine form in the excited state [32, 33] (Fig. 6). The nanoparticles exhibited the AIEE phenomenon mainly due to a restricted intramolecular motion, that is, impediment to free rotation of two end-substituted HBT units around single bonds. It is interesting to note that the... 

Liquid chromatographic techniques have been frequently employed for the separation and identification of the toxic decomposition products of synthetic dyes. Thus, the amount of aromatic amines formed from azo dyes in toys has been determined. The chemical structures of the dyes included in the investigation are listed in Fig. 3.60. The dyes were... 

A similar study was carried out using a different set of synthetic dyes. The chemical structures of the dyes are listed in Fig. 3.62. The decomposition products were separated in an ODS column (250 X 4 mm i.d. particle size 7 /tm) using an isocratic mobile phase composed of methanol-water (45 55, v/v). The flow rate was 1.2 ml/min. The contents of aromatic amines determined by spectrophotometric and HPLC methods are compiled in Table 3.24. It was established that spectrophotometry can be used for the exact determination of the amines but it is inadequate for their separation. RP-HPLC proved to be a valuable method for the analysis of this class of decomposition products [131],... 

The carcinogenic aromatic amines released from azo dyes in leather were investigated by using microwave-assisted extraction (MAE) or supercritical fluid extraction (SFE) followed by RP-HPLC. The chemical structures of dyes and aromatic amines are listed in Fig. 3.69. The flow schemes for SFE and MAE are shown in Figs 3.70. and 3.71. 

Fig. 3.69. Chemical structures of the azo colourants together with the released carcinogenic amines investigated in this study. Reprinted with permission from C. S. Eskilsson et al. [140].

Metabolites formed during the decolourization of the azo dye Reactive red 22 by Pseudomonas luteola were separated and identified by HPLC-DAD and HPLC-MS. The chemical structures of Reactive red 22 (3-amino-4-methoxyphcnyl-/fhydroxyl-sulphonc sulphonic acid ester) and its decomposition products are shown in Fig. 3.92. RP-HPLC measurements were carried out in an ODS column using an isocratic elution of 50 per cent methanol, 0.4 per cent Na2HP04 and 49.6 per cent water. The flow rate was 0.5 ml/min, and intermediates were detected at 254 nm. The analytes of interest were collected and submitted to MS. RP-HPLC profiles of metabolites after various incubation periods are shown in Fig. 3.93. It was concluded from the chromatographic data that the decomposition process involves the breakdown of the azo bond resulting in two aromatic amines [154],... 

Phenylquinoxalines - Polyphenylquinoxalines (PPQ) prepared from the reaction of aromatic bi s (o-di amines) and aromatic bis (phenyl-ot-diketones) are high temperature thermoplastics. They are process-able with little or no volatile evolution at relatively high temperatures (> 316°C) and pressure (-1.38 MPa) by virtue of their thermoplasticity. Like other thermoplastics, the processability is governed primarily by the chemical structure, molecular weight and molecular weight distribution. 

Snyder and coworkers [6] reviewed the dependence of silanol interactions on the chemical structure of the interacting base. Deductions were based on data of the relative efficacy of amine silanol blocking agents that were more popular at the time the stronger the deactivation effect of the modifier, presumably the stronger its binding to silanols. Stronger interaction of an amine or quaternary ammonium compound was said to be favored by... 

Reboxetine is the only selective and reasonably potent noradrenaline reuptake inhibitor available clinically at the present time. Reboxetine has a chemical structure not dissimilar from viloxazine, an antidepressant which was of only limited clinical interest in the 1970s because of its weak efficacy and unacceptable side effects (nausea, vomiting and occasionally seizures). Unlike the secondary amine TCA antidepressants, such as maprotiline, desipramine, nortriptyline and protriptyline, reboxetine does not affect any other transporter or receptor system and therefore is largely devoid of TCA and SSRI-like side effects. In clinical trials, reboxetine has been shown to be as effective as the SSRIs in the... 

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