Skip to content

Maiko Kawamura

Division of Pharmacognosy, Phytochemistry and Narcotics, National Institute of Health Sciences, 3-25-26, Tonomachi, Kawasaki-Ku, Kawasaki, Kanagawa, 210-9501, Japan.

11 papers in the library · 136 citations · publishing 2007-2026

Papers

The disposition into hair of new designer drugs; methylone, MBDB and methcathinone.

Journal of chromatography. B, Analytical technologies in the biomedical and life sciences August 15, 2007 Ruri Kikura-Hanajiri, Maiko Kawamura, Kazuhiro Saisho et al. 35 citations

In an animal model, the incorporation of methylone and other designer drugs into hair was measured and compared with related compounds. Methylone's hair-to-plasma concentration ratio was 14 times higher than methcathinone's, supporting earlier findings that a methylenedioxy group on the benzene ring increases incorporation. However, methylone's ratio was five-sevenths that of MDMA, suggesting a beta-carbonyl group lowers incorporation. MBDB, with a methylenedioxyphenyl-2-butanamine structure, had a higher ratio than MDMA, while methcathinone's ratio was extremely low. The authors conclude that methylone and MBDB, like methamphetamine and MDMA, have relatively high incorporation into hair, making hair samples useful for confirming retrospective use of these drugs.

Simple and Rapid Screening for Psychotropic Natural Products Using Direct Analysis in Real Time (DART)-TOFMS

YAKUGAKU ZASSHI June 1, 2009 Maiko Kawamura, Yukihiro Goda, Ruri Kikura‐hanajiri 19 citations

A rapid screening method using Direct Analysis in Real Time time-of-flight mass spectrometry (DART-TOFMS) was developed to identify psychotropic compounds in plant products of abuse in Japan without sample preparation. Among 36 products, protonated molecular ions corresponding to six hallucinogenic constituents—mescaline, salvinorin A, N,N-dimethyltryptamine, harmine, harmaline, and lysergamide—were detected in 21 products, with contents ranging from 0.05 to 45 micrograms per milligram. Results matched those from liquid chromatography-mass spectrometry. Controlled narcotics such as tetrahydrocannabinol, opioid alkaloids, and psilocin were also directly detected in marijuana, opium gum, and magic mushrooms. DART-TOFMS offers a simple, rapid screening tool for targeted psychotropic natural products, though matrix effects from other plant ingredients remain difficult to estimate.

Identification of LSD analogs, 1cP-AL-LAD, 1cP-MIPLA, 1V-LSD and LSZ in sheet products.

Forensic toxicology July 1, 2023 Rie Tanaka, Maiko Kawamura, Sakumi Mizutani et al. 18 citations

Three new analogs of LSD have been identified in paper sheet products sold as designer drugs in Japan. Using mass spectrometry and nuclear magnetic resonance spectroscopy, the compounds were determined to be 1cP-AL-LAD, 1cP-MIPLA, 1V-LSD, and LSZ. Compared to LSD, 1cP-AL-LAD is modified at two positions (N1 and N6), and 1cP-MIPLA at N1 and N18. The metabolic pathways and biological activities of 1cP-AL-LAD and 1cP-MIPLA are not yet reported. This is the first report of LSD analogs with multiple structural modifications detected in sheet products in Japan, raising concerns about future distribution and highlighting the need for continued monitoring.

Analysis of Newly Distributed Designer Drugs Detected in the Products Purchased in Fiscal Year 2008

YAKUGAKU ZASSHI February 1, 2010 Nahoko Uchiyama, Norimasa Miyazawa, Maiko Kawamura et al. 16 citations

By July 2009, Japan had designated 40 psychoactive substances (including 12 tryptamines, 17 phenethylamines, 3 piperazines, 6 alkyl nitrites, 1 diterpene, and 1 plant) as controlled substances under the Pharmaceutical Affairs Law to prevent abuse. Despite these controls, new designer drugs continue to appear in the illegal market. Analysis of two products purchased in Japan between October 2008 and February 2009 identified four compounds: three phenethylamine derivatives—N-Me-2-FMP, ALEPH-4, and DON—and one tryptamine derivative, 5-MeO-EPT. N-Me-2-FMP and 5-MeO-EPT were newly identified, while ALEPH-4 and DON were found as novel illegal drugs in Japan.

Identification of LSD Derivatives, 1cP-LSD, MIPLA and 1B-LSD in Illegal Products as Paper Sheet

YAKUGAKU ZASSHI October 31, 2020 Rie Tanaka, Maiko Kawamura, Takashi Hakamatsuka et al. 15 citations

Three new LSD-like designer drugs were identified in paper sheet products seized in Japan between September 2019 and March 2020. Using methanol extraction followed by LC-MS, high-resolution MS, GC-MS, and NMR analyses, the compounds were identified as 1cP-LSD, MIPLA, and 1B-LSD. Like other N1-acylated LSD derivatives, 1cP-LSD and 1B-LSD easily break down into LSD during GC-MS analysis, requiring caution when testing.

Identification and Analysis of LSD Derivatives in Illegal Products as Paper Sheet

YAKUGAKU ZASSHI April 30, 2020 Rie Tanaka, Maiko Kawamura, Takashi Hakamatsuka et al. 15 citations

From 2014 to 2017 in Japan, four lysergic acid diethylamide (LSD) derivatives were detected in paper sheet products sold as designer drugs. The compounds were identified as ALD-52, ETH-LAD, AL-LAD, and 1P-LSD using GC-MS, LC-MS, LC-Q-TOF-MS, and NMR analyses. Extraction methods and analytical conditions for GC-MS, LC-MS, and LC-FL were studied. As of September 2019, 2372 substances and two plants are controlled as "Designated Substances" under Japanese law. Only 1P-LSD was already regulated since April 2016; pharmacological evaluation of the other derivatives is ongoing to inform future legislation.

Characterization of the lysergic acid diethylamide analog, 1-(thiophene-2-carbonyl)-N,N-diethyllysergamide (1T-LSD) from a blotter product.

Drug testing and analysis May 1, 2024 Rie Tanaka, Maiko Kawamura, Sakumi Mizutani et al. 11 citations

A paper-sheet product sold as containing the LSD analog 1D-LSD actually contained a different, previously unreported compound: 1-thiophenoyl LSD (1T-LSD). Using mass spectrometry and nuclear magnetic resonance spectroscopy, the compound was identified as having a thiophene-2-carbonyl group instead of the claimed 1,2-dimethylcyclobutane-carbonyl group. Each unit of the sheet contained 87–100 μg of 1T-LSD free base. The compound slowly converted to LSD in methanol-d4 during analysis. Its UV spectrum differed from other LSD analogs, and its fluorescence was much lower. The authors recommend continued monitoring of sheet products for new LSD analogs.

Identification of two lysergic acid diethylamide analogs, 1-(3-(trimethylsilyl) propionyl) lysergic acid diethylamide (1S-LSD) and 1-(2-thienoyl)-6-allyl-nor-d-lysergic acid diethylamide (1T-AL-LAD), in paper sheet products distributed on the internet.

Forensic toxicology April 3, 2025 Rie Tanaka, Maiko Kawamura, Michiho Ito et al. 3 citations

Two new LSD analogs, 1S-LSD and 1T-AL-LAD, were identified in sheet products sold in Japan. Their structures were determined using gas chromatography-mass spectrometry, liquid chromatography-mass spectrometry, and nuclear magnetic resonance. A trace amount of iso-1S-LSD, a C8-epimerization product, was also suggested in one product. This is the first report of these compounds in sheet products in Japan. The metabolic pathways and biological activities of 1S-LSD and 1T-AL-LAD remain unexplored, and further investigation into their possible in vivo deacylation and conversion into LSD or AL-LAD is needed.

[Identification of Three Arylcyclohexylamines (MXPr, MXiPr, and DMXE) in Illegal Products].

Yakugaku zasshi : Journal of the Pharmaceutical Society of Japan January 1, 2022 Rie Tanaka, Maiko Kawamura, Sakumi Mizutani et al. 3 citations

Three new derivatives of the dissociative drug methoxetamine (MXE) were identified in illegal products in Japan: methoxpropamine (MXPr), methoxisopropamine (MXiPr), and deoxymethoxetamine (DMXE). MXE itself, an analog of the anesthetic ketamine, is already controlled as a narcotic in Japan, and its overdoses have caused health problems. All arylcyclohexylamines, including these new substances, act as antagonists of the NMDA receptor. The findings highlight the ongoing emergence of novel psychoactive substances designed to evade legal controls.

Structural analysis of an lysergic acid diethylamide (LSD) analogue N-methyl-N-isopropyllysergamide (MiPLA): Insights from Rotamers in NMR spectra.

Drug testing and analysis June 1, 2024 Takuji Shoda, Genichiro Tsuji, Maiko Kawamura et al. 1 citation

Lysergic acid diethylamide (LSD) is a hallucinogen that activates the serotonin 2A receptor and is a controlled substance in Japan. Recently, MiPLA, an N-methyl-N-isopropyl derivative of LSD, has appeared in paper-sheet products in several countries. This work describes the three-step synthesis of MiPLA starting from ergometrine maleate, which also produced the (8S)-isomer, iso-MiPLA, as a by-product. Liquid chromatography-mass spectrometry showed that LSD, MiPLA, and iso-MiPLA have different retention times. Nuclear magnetic resonance spectroscopy determined their chemical structures and revealed rotamers involving the N-methyl-N-isopropyl groups of tertiary amides in MiPLA and iso-MiPLA.

Identification and Analysis of Lysergic Acid Diethylamide Analogs, 4‐Benzoyl‐ N,N ‐Diethyl‐7‐Methyl‐4,6,6a,7,8,9‐Hexahydroindolo[4,3‐ fg ]quinoline‐9‐Carboxamide (1Bz‐LSD) and N , N ‐Diethyl‐7‐Methyl‐4‐(4‐(Trimethylsilyl)Benzoyl)‐4,6,6a,7,8,9‐Hexahydroindolo[4,3‐ fg ]quinoline‐9‐Carboxamide (1‐TMSBz‐LSD), in tablet or paper sheet products available online in Japan

Drug Testing and Analysis February 18, 2026 Rie Tanaka, Maiko Kawamura, Michiho Ito et al.

Two new lysergic acid diethylamide (LSD) analogs, 1Bz-LSD and 1-TMSBz-LSD, were identified in tablet and paper sheet products sold in Japan. Using gas chromatography-mass spectrometry, liquid chromatography-photodiode array-mass spectrometry, liquid chromatography with hybrid quadrupole time-of-flight mass spectrometry, and nuclear magnetic resonance, the structures of the compounds were determined. 1Bz-LSD was found in a tablet product, and 1-TMSBz-LSD was found in a paper sheet product. This is the first report of these specific analogs being detected in such products in Japan.