Phenethylamines analysis

Figure 11.14 Analysis of amphetamines by GC-NPD following HS-SPME exti action from human hair (a) Normal hair (b) normal hair after addition of amphetamine (1.5 ng) and methamphetamine (16.1 ng) (c) hair of an amphetamine abuser. Peak identification is as follows 1, a-phenethylamine (internal standard) 2, amphetamine 3, methamphetamine 4, N-propyl-/3-phenethyamine (internal standard). Reprinted from Journal of Chronatography, B 707,1. Koide et ai, Determination of amphetamine and methamphetamine in human hair by headspace solid-phase microextraction and gas cliromatography with niti ogen-phosphoms detection, pp. 99 -104, copyright 1998, with permission from Elsevier Science.

A sensitive method for primary amines is shown in reaction 2, leading to the corresponding 7V-benzenesulfonyl-/V-trifluoroacetyl derivatives. These can be determined by GC-ECD using SE-30 columns LOD 1-5 pg, which is about 200 times more sensitive than GC-FID. The method was applied for determination of phenethylamine (33) in urine110. This analysis was performed also by LLE into n-pentane, derivatization to the benzenesulfonamide and GC-FPD using a capillary column recoveries of aliphatic primary amines in urine were 91-107%, RSD 0.2-4.5%111,112. Amines in environmental waters and sediments were determined after LLE with dichloromethane, derivatization with benzenesulfonyl chloride and GC-SIM-MS LOD 0.02-2 pg/L of water and 0.5-50 ng/g of sediment113. 

Tao QF, Zeng S. 2002. Analysis of enantiomers of chiral phenethylamine drugs by capillary gas chromatography/ mass spectrometry/fLame-ionization detection and precolumn chiral derivatization. J Biochem Biophys Methods 54 103. 

Fales and Pisano (30) were the first to describe the gas chromatographic analysis of amphetamine. They used 4% SE-30 in a silanized glass column and an argon ionization detector for the separation of (3-phenethylamine, amphetamine, norephedrine, eph drine, histamine, tyramine, dimethyltriptamine, tryptamine, 5-methoxytryptamine, benzylamine, N-methylbenzylamine, octopamine, synephrine, normetanephrine, serotonin, N-acetyltryptamine, find melatonin. The method was also used for the analysis of amphetamine extracted from urine. 

Yonekura, T., Kamata, S., Wasa, M., Okada, A., Kawata, S., Tarul, S. Simultaneous analysis of plasma phenethylamine, phenylethanolamine,... 

Bogusz et al. [68] reported the LC-APCI-MS analysis of sixteen phenethylamines after SPE. Subsequently, optimization of the mobile-phase composition for the LC-ESI-MS analysis of methylamphetamine and related compounds was described [69]. Methanol in the mobile phase resulted in a slightly higher abundance of the [M+H]. Formic acid was preferred over other additives. Microporous ultrafiltration was used in the sample pretreatment of urine samples. The intra-assay and inter-assay precision and accuracy in the 100-1000 ng/ml range were 2.3-6.3%, 0.8-5.9%, and 1.6-6%, respectively, for amphetamine in urine. 

Sample preparation and derivatization methods for GC analysis of BAs have been also proposed. In a method developed by Daudt and Ough (1980), amines are distilled from the alkalized grape juice or wine sample and trapped in an acidified solution. After concentration under vacuum, methylamine, dimethylamine, ethylamine, diethylamine, n-propylamine, isobutylamine, a-amylamine, isoamylamine, pyrrolidine, and 2-phenethylamine in their salt form are derivatized with triflu-oroacetic (TFA) anhydride. TFA derivatives are extracted with ethyl ether and analyzed by GC-MS with a capillary fused silica poly( ethylene) glycol (PEG) column and the following oven temperature program 8 min at 70 °C, l°C/min to 160 °C, isotherm for 90 min. 

One consisted of a mobile phase of methanol - water - U acetic acid (40 59 1) containing 0.02 M methanesulfonic acid (pH 3.5) in combination with a microparticulate octadecyl column. It was recommended for samples containing compounds such as barbiturates, local anaesthetics, LSD and related alkaloids. The other system made use of the same column and a mobile phase of methanol - water - 1% acetic acid (20 79 1) containing 0.02 M methanesulfonic acid (pH 3.5). It was particularly suitable for the analysis of phenethylamines and for the separation of heroin and acetyl codeine. The increased counter-ion concentration in these mobile phases compared to previously used systems was applied to reduce the... 

Amphetamines and Phenethylamines. Deficiency in the p-hydroxylation of amphetamine was one of the observations that led to the discovery of the CYP2D6 polymorphism (Bring et al. 1970 Smith 1986). A single oral administration of the radiolabelled enantiomers of amphetamine to three volunteers with subsequent analysis of urine indicated that about 5 percent of (+)-amphetamine was converted to p-hydroxyamphetamine in two subjects but to a much less extent in the third subject, who was later found to have CYP2D6 deficiency (Smith 1986). The main excretion product was unchanged amphetamine (although the extent of excretion is known to be pH dependent), and the major metabolites were products of side... 

Possibly as a result of the social implications of the hallucinogenic j5-phenethyl-amines and simple isoquinoline alkaloids, a large number of new plant species suspected to contain these structural types have been closely scrutinized with the aid of sensitive analytical methods. Thus, extensive screening of a large variety of cactus species has been carried out. G.c. analysis has indicated the presence of trace amounts of dimers and trimers of phenethylamine and tetrahydroiso-quinoline types " while combination g.c.-mass spectrometry has enabled rapid identification of alkaloids of 120 cactus species." High voltage electrophoresis has been used for quantitative alkaloid determination.Useful structural information may be obtained from the technique of chemical ionization mass spectrometry. ... 

H.J. Weintraub, A.J. Hopfinger, Conformational analysis of some phenethylamine molecules, J. Theor. Biol. 1973, 41, 53-75. 

In the amine oxidase from Escherichia coli, the topa quinone was confirmed by a detailed analysis of the cofactor dipeptide X-Asp [67] and the resonance Raman spectrometry of the enzyme and its derivatives[68,69]. The primary structure of the enzyme also contains the cofactor consensus sequence [70]. More bacterial genes were shown to encode proteins containing the topa quinone consensus sequence, such as amine oxidase from Klebsiella aerogenes [71], phenethylamine oxidase and histamine oxidase from Arthrobacter globiformis [72,73], and methylamine oxidase from Arthrobacter strain PI [74]. Amino acid sequences around the position of the cofactor for selected amine oxidases from various sources are given in Table 1. 

The N-glutaminoyl-2-phenethylamine derivatives [50 R = CH(Me)Et] and [50 R = CH(Me)Me], have been isolated from Croton humilis. Interpretation of all the high-resolution mass spectral peaks exceeding 4 % (including the assignment of all metastables) together with a complete analysis of the 100 MHz n.m.r. 

The atropisomers of 336 were resolved by diastereomer crystallization with (S)-a-phenethylamine. The ee of the process can be monitored by chiral HPLC after methylation of the acids. X-ray structure analysis allowed the assignment the R configuration to the (+) enantiomer. The absolute configuration was also confirmed by comparison of the experimental CD spectra using ethanol with the ZINDO calculated one. 

Only one illustrative example is given here to describe and explain the proper application of Hansch analysis (for further examples see chapter 7). Graham and Karrar [397] determined the antiadrenergic activities of a series of a-bromo-phenethylamines (8). Hansch and Lien [398] derived eq. 63, which was at this time considered to give the best quantitative description of the data (Table 12 only some... 

Table 13. Antiadrenergic activities of meta- and para-subsliluted N,N-dimethyl-a-brotno-phenethylamines (12) tabic for Free Wilson analysis [391, 393]...

In a Free Wilson analysis of norepinephrine-uptake inhibiting phenethylamines (50), including achiral analogs, racemates, and pure enantiomers, but also diastereomeric mixtures, different group contributions were attributed to the R and S substituents (9 variables n = 30 r = 0.963 s = 0.276) [812]. 

Specific and sensitive r-adioiramune assays were developed for analysis of LSD and mescaline in biological fluids.586-8 Furthermore, antibodies were obtained which exhibited high specificity to LSD and cross-reactivity to other psychotomimetics related to tryptamine and phenethylamine. 589... 

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