Determination of primary

The determination of primary amines on the macro scale is most conveniently carried out by titration in non-aqueous solution (Section 10.41), but for small quantities of amines spectroscopic methods of determination are very valuable. In some cases the procedure is applicable to aromatic amines only, and the diazotisation method described for determination of nitrite (Section 17.38) can be adapted as a method for the determination of aromatic primary amines. On the other hand, the naphthaquinone method can be applied to both aliphatic and aromatic primary amines. 

MOLECULAR BIOLOGY HAS REVOLUTIONIZED THE DETERMINATION OF PRIMARY STRUCTURE... 

DNA cloning and molecular biology coupled with protein chemistry provide a hybrid approach that greatly increases the speed and efficiency for determination of primary strucmres of proteins. 

Huidobro, J. F., Estrella, R. M., de Andrade, B. P. C., Sanchez, M. P., Sancho, M. T., Muniategui, S., and Simal-Lozano, J. (1994). Enzymatic determination of primary normal alcohols as apparent ethanol content in honey. /. Agric. Food Chem. 42,1975-1978. 

Liu, J., Hsieh, Y.-Z., Wiesler, D., Novotny, M., Design of 3-(4-carboxybenzoyl)-2-quinolinecarboxaldehyde as a reagent for ultrasensitive determination of primary amines by capillary electrophoresis using laser fluorescence detection, Anal. Chem., 63, 408, 1991. 

This also explains the use of pyridine in acetic anhydride as an acetylating reagent6 in the determination of primary or secondary alcohols and amines according to the following sequential reactions (with ROH as an example) ... 

Substitution as a preceding reaction. In addition to the well known determination of primary and secondary alcohols via esterification with acetic anhydride in pyridine at about 98° C, esterification is possible at room temperature in ethyl acetate with perchloric acid117 or 2,4-dinitrobenzenesulphonic acid118 as a catalyst. However, as tertiary alcohols preferably split off their hydroxy group, they can be adequately determined by OH-substitution with HBr in glacial acetic acid according to... 

Citron IM, Allan M (1964) Spectrophotometric determination of primary amines in aqueous solution with copper-(ethylenedinitrilo) tetraacetic acid. Anal Chem 36(1) 208-210... 

Modifications of the Bratton-Marshall method mentioned in Section IV.D.3.g can be used for sensitive spectrophotometric detection and determination of primary aromatic and heterocyclic amines. Thus, a simple spectrophotometric determination of the cardioprotective agent acadesine (142) was developed, to measure concentrations of the drug in plasma during intravenous infusion to patients undergoing coronary artery bypass graft surgery336. 

A spectrophotometric method for determination of primary and secondary amines requires development for each particular compound, determining the kinetics of reaction of the amine with sodium l,2-naphthoquinone-4-sulfonate (143) and the UVV absorption spectrum of the product, under a set of fixed conditions. The procedure was applied to determination of ephedrine (30) and amphetamine (28) in pharmaceutical samples339. Reagent 143 in a FLA. system was used for the fast determination of lysine (144) in commercial feed samples by multivariate calibration techniques, without need of chromatographic separation340. 

Brede, C., Skjevrak, I. and Herikstad, H. (2003). Determination of primary aromatic amines in water food simulant using solid-phase analytical derivatization followed by gas chromatography coupled with mass spectrometry, J. Chrom. A, 983, 35-42. 

In recent years, C-NMR spectroscopy has found extensive use in studies on carbohydrate polymers, in some series overshadowing the importance of H-NMR spectroscopy. Applications range through determination of primary structure, analysis of mixtures, monitoring of chemical and enzymic transformations or of chelation reactions, and studies on conformational change. Measurements of coupling are utilized in determining the... 

DeLeenheer, A., Sinsheimer, J.E., and Burckhalter, J.H., Fluorometric determination of primary and secondary aliphatic amines by reaction with 9-isothiocyanatoacridine, J. Pharm. Sci., 62, 1370, 1973. 

Noguchi T, Miyazaki S, Morii I, et al. Percutaneous transluminal coronary angioplasty of chronic total occlusions. Determinants of primary success and long-term clinical outcome. Catheter Cardiovasc Inter 2000 49 258-264. 

Table I. Techniques Used for Determination of Primary Structure...

The fundamental work of Lemieux and coworkers21 introduced the successful application of H-n.m.r. spectroscopy to structural problems in the carbohydrate field. Since then, numerous studies have been devoted to the (partial) determination of primary structures of carbohydrates and derivatives thereof, as well as to the elucidation of their conformation in solution, by means of H-n.m.r. spectroscopy. An exhaustive discussion of all these contributions is beyond the scope of this article. For comprehensive reviews, see Refs. 22-28. 

Lee, R. C., Burton, R. A., Hrmova, M., and Fincher, G. B., Barley arabinoxylan arabinofuranohydrolases purification, characterization and determination of primary structures from cDNA clones. Biochem 72001, 356 (Pt 1), 181-9. 

Several physicochemical methods of investigation, such as measurement of optical rotation (including optical rotation dispersion and circular dichroism) rheological methods, and X-ray analysis of fibers and films, have played a very important role for determination of conformations of galactan molecules and characterization of their supramolecular structures.8,19 As mentioned in Section I, only physicochemical methods used for determination of primary structures of polysaccharides are considered in this chapter. 

Bergstrom and Lindgren s Determination of Primary Hydration Number from IR Measurements (Transition-MetaMons and Lanthanides)... 

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