Amino compounds detection

Kugler, F. et ah. Determination of free amino compounds in betalainic fruits and vegetables by gas chromatography with flame ionization and mass spectrometric detection, J. Agric. Food Chem., 54, 4311, 2006. 

Several factors indicate that the amino acids detected in all of these carbonaceous chondrites are indigenous and that they must have originated abiotically. First, the presence of protein and non-protein amino acids, with approximately equal quantities of D and L enantiomers points to a nonbiological origin and precludes terrestrial contamination. In addition, the non-extractable fraction of the Murchison is significantly heavier in 13C than terrestrial samples. Finally, the relative abundances of some compounds detected resemble those of products formed in prebiotic synthesis experiments. The aliphatic hydrocarbons are randomly distributed in chain length, and the C2, C3, and C4 amino acids have the highest concentrations (i.e., the most easily synthesized amino acids with the least number of possible structures are most abundant) [4]. 

Si structure 251 smallpox 70 soil nitrogen compounds detected by 15N NMR, amides/peptides 126 amino adds 126 difficulties encountered with the method 126-127... 

The reduction of 2, either catalytically or with zinc in acetic acid, leads to 3-amino-4-hydroxy-2-quinolone 20 [72TH000], These amino compounds are rather unstable they dimerize with loss of ammonia to "bis-amines", which in turn are readily oxidized to dyes similar to those obtained from ninhydrin and primary amines [68M1205] [68M1543], The amino derivatives 20 are therefore conveniently converted into 0,N-diacetyl derivatives, the N-acetyl derivative 21, or its dehydrated form, the oxazolo derivative 22 [95MI000], The variety of biological activity of oxazolo-quinolines of type 22 has been detected only in recent years [94JHC1647],... 

Czuba has studied the amination (KNH2 in liquid NH3, —33°, 4 hr.) of the three bromo-l,5-naphthyridines. The 3-bromo derivative gave an 82% yield of the 3-amino and a 13% yield of the 4-amino compound no 2-amino derivative (via l,5-naphthyrid-2,3-yne) was detectable. The 4-bromo compound gave a 70% yield of the 3-amino and a 20 % yield of the 4-amino derivative the higher proportion of the latter indicates some 8 Ar2 substitution is occurring along with the predominant l,5-naphthyrid-3,4-yne mechanism. The ratio of 3- to... 

The electrochemical detection system requires reducible or oxidable substances. The eluted substance is reduced or oxidized by an electrode. This not very common detection system is a useful tool for determination of amino-compounds and other organic nitrogen-compounds, phenols and quinones [8],... 

Numerous individual substances were detected only in Ru04 extracts e.g. di- to pentachlorinated benzenes, 4-chlorobenzoic acid and 2,4-dichlorobenzoic acid 24, hexachlorocyclohexanes (a-,P-,y- and 5-HCH) 22, a technical mixture obtained during the synthesis of lindane, and the plasticizers alkylsulfonic acid phenylesters 23. These plasticizers were recently identified in riverine sediments (Franke et al. 1998). Furthermore, nitro-substituted benzoic acid and alkylated phenols 24 were observed. The occurrence of aromatic nitro compounds as a result of the oxidation of anilines can be excluded due to the contemporary appearance of amino compounds, e.g. 4-aminobenzoic acid or N-ethylaniline. However, the origin as well as the emission pathway of these compounds is still unknown. 

Most of the amino acids (Table 5.III) and many unidentified amino compounds have been detected in root exudates but not in all plants examined. These findings harmonize well with the observations of Lochhead and associates, as well as with those of Katznelson, that many of the rhizosphere bacteria have special amino acid requirements, and the higher plants can supply them. 

Cao, L., Wang, H., and Zhang, H., Analytical potential of 6-oxy-(A-succinimidyl acetate)-9-(2 -methoxycarbonyl) fluorescein for the determination of amino compounds by capillary electrophoresis with laser-induced fluorescence detection. Electrophoresis, 26, 1954, 2005. 

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