Metabolism of the psychotomimetic tryptamine derivative 5-methoxy-N,N-diisopropyltryptamine in humans: identification and quantification of its urinary metabolites.
The urinary metabolites of 5-methoxy-N,N-diisopropyltryptamine (5-MeO-DIPT) in humans have been investigated by analyzing urine specimens from its users. For the unequivocal identification and accurate quantification of its major metabolites, careful analyses were conducted by gas chromatography/mass spectrometry, liquid chromatography/mass spectrometry, and liquid chromatography-tandem mass spectrometry, using authentic standards of each metabolite synthesized. Three major metabolic pathways were revealed as follows: 1) side chain degradation by O-demethylation to form 5-hydroxy-N,N-diisopropyltryptamine (5-OH-DIPT), which would be partly conjugated to its sulfate and glucuronide; 2) direct hydroxylation on position 6 of the aromatic ring of 5-MeO-DIPT, and/or methylation of the hydroxyl group on position 5 after hydroxylation on position 6 of the aromatic ring of 5-OH-DIPT, to produce 6-hydroxy-5-methoxy-N,N-diisopropyltryptamine (6-OH-5-MeO-DIPT), followed by conjugation to its sulfate and glucuronide; and 3) side chain degradation by N-deisopropylation, to the corresponding secondary amine 5-methoxy-N-isopropyltryptamine (5-MeO-NIPT). Of these metabolites, which retain structural characteristics of the parent drug, 5-OH-DIPT and 6-OH-5-MeO-DIPT were found to be more abundant than 5-MeO-NIPT. Although the parent drug 5-MeO-DIPT was detectable even 35 h after dosing, no trace of its N-oxide was detected in any of the specimens examined.
Kamata
Tooru
T
Forensic Science Laboratory, Osaka Prefectural Police Headquarters, 1-3-18, Hommachi, Chuo-ku, Osaka 541-0053, Japan. t-kamata@mahoroba.ne.jp.
Katagi
Munehiro
M
Kamata
Hiroe T
HT
Miki
Akihiro
A
Shima
Noriaki
N
Zaitsu
Kei
K
Nishikawa
Mayumi
M
Tanaka
Einosuke
E
Honda
Katsuya
K
Tsuchihashi
Hitoshi
H
D008735:5-Methoxytryptamine / Q000031:analogs & derivatives* / Q000378:metabolism / Q000506:poisoning / Q000652:urine; D000328:Adult; D002853:Chromatography, Liquid; D003704:Dementia / Q000139:chemically induced; D008401:Gas Chromatography-Mass Spectrometry; D006213:Hallucinogens / Q000378:metabolism* / Q000506:poisoning / Q000652:urine; D006801:Humans; D008297:Male
D006213:Hallucinogens; C033696:5-methoxy-N,N-diisopropyltryptamine; D008735:5-Methoxytryptamine