Cathinone is relatively unstable and oxidizes at room temperature into (+)-norpseudoephedrine and norephedrine within a few days of picking or if the leaf is dried (Kalix 1991; Szendrei 1980).
The three main psychoactive alkaloids present in khat leaves, cathinone, cathine and norephedrine, are psychostimulants structurally and pharmacologically similar to amphetamine.
Adipokinetix[TM], a dietary supplement advertised as a "Fat Burner," contains the phenylethylamine, 1R, 2S norephedrine
HCI (NEP; 25 mg), the methylxanthines caffeine (C) and theophylline (T) (each 50 mg), and the [alpha]2-adrenoceptor antagonist, yohimbine (Y; 3 mg).
DETERMINATION OF CATHINONE, CATHINE, AND NOREPHEDRINE IN URINE BY GC-MS
5] heptafluorobutyramide (HFBA), 13 166, 167; cathinone HFBA, 10 77, 240; cathine bis-HFBA, 330, 303, 240; norephedrine bis-HFBA 330, 303, 240.
To confirm whether cathinone, cathine, or norephedrine exhibited cross-reactivity with the antibodies of the Mahsan immunoassay, we added one of the three alkaloids in a concentration of 50 mg/L to three portions of a drug-free urine.
To investigate the nature of the unknown peak, we added 10 mg/L cathinone or norephedrine to drug-free urines, and both were analyzed with the Remedi HS system.
For derivatization, we selected heptafluorobutyrylation using MBHFBA because the derivatives of the diastereomers cathine and norephedrine are well separated by GC.
In the urine samples from the study, the phenylpropanolamines cathine and norephedrine could be detected in the MS scan mode up to 50-70 h after kath ingestion; in the MS-SIM mode, the compounds were still detectable at concentrations up to 0.
A previously published gas chromatography-mass spectrometry method (3, 4) was used to verify the absence of the following amphetamine-related compounds: amfepramone, amphetamine, benzodioxazoylbutanamine, benzphetamine, clobenzorex, dexfenfluramine, dimethoxybromoamphetamine, dimethoxymethylamphetamine, fencamfamin, fenproporex, mefenorex, methamphetamine, methoxyphenamine, methylbenzodioxazolylbutanamine, methylenedioxyamphetamine, methylenedioxyethamphetamine, methylenedioxymethamphetamine, methylphenidate, 4methylthioamphetamine, norephedrine
, norfenfluramine, phentermine, and pseudoephedrine.