Preparative isolation

It had been observed that Octa is predominantly heptabromo DPF (ref. 3). The predominant peak (Fig. IB, peak 4) is here identified as the isomer 2,2, 3,4,4, 5, 6 heptabromo DPF by interpreting the NMR spectrum (Table 1) of material isolated preparatively. 

Oligosaccharides were isolated preparatively by high-pH anion exchange chromatography carried out on a LC-system (Dionex Corporation, Sunnyvale CA) equipped with a CarboPac PA-1 column (9 x 250 mm), coupled to a Spectra System AS 3500 auto sampler. The detection was carried out using Pulsed Amperometric Detection (PAD-II). 

Sarnecka-Keller (SI), by use of Bondzynski s method modified by Gawinski, isolated from normal urine a well-defined peptide fraction easily reproducible without change of qualitative composition. Throughout the isolation procedure all factors which may have caused any changes in peptide structure were taken into account. The isolated preparation was substantially similar in general properties to that obtained originally by Bondzynski et al. (B7). 

Khan AR, Bengtsson B, Lindberg S (1986) Influence of substance P on ciliary beat frequency in airway isolated preparations. Eur J Pharmacol 130(1-2) 91-96. 

From an exhaustive potentiostatic electrolysis, the product(s) formed at the selected electrode potential can be isolated. Preparative and analytical techniques are available to determine the composition of the product mixture and the structure of its components. Mechanistic reasoning will often allow defining the reaction steps. Even more information about the reaction can be gained from electrolysis experiments at various defined potentials, for example, after each peak in the cyclic voltammogram of the substrate. 

Markovic and Hartwig isolated and characterized the first intermediate in iridium-catalyzed allylic substitution [100]. They isolated the metalacyclic iridium-phosphor-amidite fragment containing COD and the olefinic portion ofN- l -phenylallyl)aniline, the product of the allylic substitution reaction between cinnamyl carbonate and aniline (5 in Scheme 22). This complex containing the product of allylic substitution was first detected by NMR spectroscopy during catalytic reactions. It was then isolated, prepared independently, and shown to be chemically and kinetically competent to be an intermediate in allylic substitutions. 

Hermansson ( ) has studied the effect of Nal, NaCl, NaC2H302, Na2S04 and CaCl2 on the solubility of an isolate prepared under mild conditions. There has been no corresponding work reported for denatured soy isolates. Thus, what follows is an evaluation of the effects of neutral salts on the solubility of native and denatured soy isolates. 

Korolczuk and Rutkowski (78) examined the amino acid content of rapeseed isolates prepared by several methods. Glucosinolates were not present. They found that isolates are generally characterized by higher levels of essential amino... 

Isolation/Preparation/Mutation/Application Source/tissue... 

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