Aminocarboxylates

Supplement 1942 195-449 Hydroxy-amines Aminoethyl alcohol, 274. Carbonyl-amines Aminoacetaldehyde, 307. Aminoacetone, 314. Hydroxy-carbonyl amines Glucosamine, 328. Aminocarboxylic acids Glycine, 333. Hydroxylamines, 534. Hydrazines, 546. Azo Compounds. 562. Oryano-metallic Compounds, 580. 

The utility of complexation titrations improved following the introduction by Schwarzenbach, in 1945, of aminocarboxylic acids as multidentate ligands capable of forming stable 1 1 complexes with metal ions. The most widely used of these new ligands was ethylenediaminetetraacetic acid, EDTA, which forms strong 1 1 complexes with many metal ions. The first use of EDTA as a titrant occurred in... 

EDTA is one member of a class of aminocarboxylate ligands that form very stable 1 1 complexes with metal ions. The following table shows log Kf values for several ligands with Ca + and Mg +. Which ligand is the best choice for the direct titration of Ca + in the presence of Mg + ... 

The process implications of equation 3 go beyond the weU-known properties (27—29) of NMP to faciUtate S Ar processes. The function of the aminocarboxylate is also to help solubilize the sulfur source anhydrous sodium sulfide and anhydrous sodium hydrogen sulfide are virtually insoluble in NMP (26). It also provides a necessary proton acceptor to convert thiophenol intermediates into more nucleophilic thiophenoxides. A block diagram for the Phillips low molecular weight linear PPS process is shown in Eigure 1. 

The reaction of amino acid imidazolides with the potassium salt of monomethyl malonate in the presence of one equivalent of MgCl2, CoCl2, or MnCl2 results in the formation of jS"keto-y-aminocarboxylates.[64]... 

Another synthesis of jS-keto-y-aminocarboxylates starts from TV-protected amino-acid imidazolides and magnesium p-nitrobenzyl malonate (50-60 °C, about 6h).[65]... 

Recently, a novel process for the preparation of chromia promoted skeletal copper catalysts was reported by Ma and Wainwright (8), in which Al was selectively leached from CuA12 alloy particles using 6.1 M NaOH solutions containing different concentrations of sodium chromate. The catalysts had very high surface areas and were very stable in highly concentrated NaOH solutions at temperatures up to 400 K (8, 9). They thus have potential for use in the liquid phase dehydrogenation of aminoalcohols to aminocarboxylic acid salts. 

In today s discussion of the origin of life, the RNA World (Chapter 6) is seen as much more important, and is much better publicized, than the protein world . However, nucleic acids and proteins are of equal importance for the vital metabolic functions in today s life forms. Peptides and proteins are constructed from the same building blocks (monomers), the aminocarboxylic acids (generally known simply as amino acids). The way in which the monomers are linked, the peptide bond, is the same in peptides and proteins. While peptides consist of only a few amino acids (or to be more exact, amino acid residues), proteins can contain many hundreds. The term protein (after the Greek proteuein, to be the first) was coined by Berzelius in 1838. 

After hydrolysis of the nitrile to the aminocarboxylic acid, the authors obtained the dipeptide diglycine (Gly-Gly) and the tripeptide Gly-Gly-Gly. 

For low molecular weight Gd111 chelates, it is mainly fast rotation that limits proton relaxivity (Figure 3). In order to circumvent this problem, Gd111 poly(aminocarboxylates) have been linked via either covalent or noncovalent interactions to different macromolecules. 

The DELFIA assay, the first effective lanthanide-based immunoassay, was developed and commercialized by the early 1980s.108-112 DELFIA (Dissociation Enhanced Lanthanide Fluoro-ImmunoAssay) is a heterogeneous assay which uses a lanthanide complex based on aminocarboxylate ligands such as EDTA, EGTA, or DTPA, linked to the antibody by reaction of appended isothiocyanate groups (e.g., complex (45)) with nucleophilic residues, particularly amines, on the protein surface (Figure 11). 

Fig. 1. Approximate pH values and ranges for a selection of biochemical and geochemical environments, with their relation to successive pK values for the aminocarboxylate ligand ethylene glycol bis-(2-aminoethyl ether)-tetraacetate, egta.

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