Ephedrine

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Tetsuo Nagano - One of the best experts on this subject based on the ideXlab platform.

  • use of stable isotope ratios for profiling of industrial Ephedrine samples application of hydrogen isotope ratios in combination with carbon and nitrogen
    Forensic Science International, 2009
    Co-Authors: Naoki Kurashima, Yasuteru Urano, Yukiko Makino, Kaori Sanuki, Yukari Ikehara, Tetsuo Nagano
    Abstract:

    Abstract The utility of hydrogen stable isotope ratio measurement by IR-MS for establishing the origin of Ephedrine and pseudoEphedrine (Ephedrines), precursors of methamphetamine, was evaluated. There are two kinds of commercial semisynthetic Ephedrines, one produced from molasses and the other from pyruvic acid. While the semisynthetic Ephedrines derived from pyruvic acid cannot be discriminated from biosynthetic Ephedrines and synthetic Ephedrines based on δ 13 C and δ 15 N values, they could be identified from the δ 2 H values. The low deuterium content of biosynthetic Ephedrines (δ 2 H: −193 to −151‰) allows a clear distinction from synthetic Ephedrines (δ 2 H: −73 to −30‰), semisynthetic Ephedrines derived from pyruvic acid (δ 2 H: +75 to +148‰) and semisynthetic Ephedrines derived from molasses (δ 2 H: −74 to +243‰). The wide range of δ 2 H values of semisynthetic Ephedrines is therefore very useful for the detailed classification of Ephedrines, in combination with the measurement of δ 13 C and δ 15 N values as described in our previous work. This study was carried out on a limited number of samples reflecting the various routes of Ephedrines manufacture. But it has become apparent that this stable-isotope analysis is an appropriate means by which to screen for manufacturing process of Ephedrines. This approach should be useful for worldwide precursor control of methamphetamine.

  • Evaluation of characteristic deuterium distributions of Ephedrines and methamphetamines by NMR spectroscopy for drug profiling.
    Analytical Chemistry, 2008
    Co-Authors: Teruki Matsumoto, Yasuteru Urano, Yukiko Makino, Ruri Kikura-hanajiri, Nobuo Kawahara, Yukihiro Goda, Tetsuo Nagano
    Abstract:

    We have established a method for quantitative analysis of the deuterium contents (D/H) at the phenyl, methine, benzyl, N-methyl and methyl groups of l-Ephedrine/HCl, d-pseudoEphedrine/HCl and methamphetamine/HCl by 2H NMR spectroscopy. Comparison of the 5 position-specific D/H values of l-Ephedrine/HCl and d-pseudoEphedrine/HCl prepared by three methods (chemical synthesis, semichemical synthesis, and biosynthesis) showed that chemically synthesized Ephedrines and semisynthetic Ephedrines have highly specific distributions of deuterium at the methine position and at the benzyl position, compared with the other positions. The classification of several methamphetamine samples seized in Japan in terms of the D/H values at these two positions clearly showed that the methamphetamine samples had been synthesized from Ephedrines extracted from Ephedra plants or semisynthetic Ephedrines but not from synthetic Ephedrine. This isotope ratio analysis method should be useful to trace the origins of seized methampheta...

  • determination of origin of Ephedrine used as precursor for illicit methamphetamine by carbon and nitrogen stable isotope ratio analysis
    Analytical Chemistry, 2004
    Co-Authors: Naoki Kurashima, Yasuteru Urano, Yukiko Makino, Setsuko Sekita, Tetsuo Nagano
    Abstract:

    The sale of Ephedrine, one of the precursors of methamphetamine, is strictly controlled and monitored in various countries to prevent the production of illicit methamphetamine. There are three kinds of production scheme for Ephedrine manufacture, and it is very useful for precursor control to investigate the origin of Ephedrine used for the synthesis of illicit methamphetamine. By means of stable isotope ratio mass spectrometry (IR-MS), we investigated the origin of Ephedrine based on the δ13C and δ15N values. The various origins of Ephedrine (biosynthetic, semisynthetic, or synthetic) could be discriminated clearly by using these values. The δ15N values of synthetic Ephedrine were more negative than those of Ephedrine from other sources. By the repeated distillation of methylamine in our laboratory, we confirmed that this could be due to isotope separation during distillation for the purification of methylamine used for Ephedrine synthesis. The values for Ephedrine used as the precursor were well-correla...

Yukiko Makino - One of the best experts on this subject based on the ideXlab platform.

  • Trial analysis of drug profiling by liquid chromatography/mass spectrometry and inductively coupled plasma mass spectrometry to establish the origin of Ephedrines used as precursors for illicit production of methamphetamine.
    Rapid Communications in Mass Spectrometry, 2019
    Co-Authors: Yukiko Makino, Yasuteru Urano, Kiyoko Kaneko
    Abstract:

    Rationale We investigated whether chemical information on the origin of Ephedrine and pseudoEphedrine (Ephedrines) can be acquired by liquid chromatography/mass spectrometry (LC/MS) as a substitute method for stable isotope ratio mass spectrometry (IRMS), which is not routinely available in forensic laboratories. We examined the characteristic inorganic elemental contaminants of Ephedrines as a preliminary study. Methods The stable isotope ratios measured by IRMS analysis are expressed relative to the stable isotope ratios of conventional standards. Referring to the method using validated standard samples in IRMS, we selected a standard sample for acquiring stable isotopic ratio by LC/MS. The abundance ratio of the [M + 2H]+ ion to the [M + H]+ ion was measured by means of selected ion monitoring. We carried out qualitative analysis of inorganic elements contained in Ephedrines produced by different manufacturing methods with ICPMS. Results We found that the ratio of stable isotope ion to molecular ion (stable isotope ratio) of Ephedrines could be measured with LC/MS. The stable isotope ratio of Ephedrines determined by LC/MS were confirmed to show relatively good correlations with the carbon and hydrogen stable isotope ratios found by IR-MS. We identified strontium as a characteristic inorganic element contained in Ephedrines prepared by the semisynthetic method from molasses, or in the biosynthetic method from ephedra plants. Conclusions Our results suggest that useful chemical information can be obtained by LC/MS, which is easy to carry out, and is generally available in forensic laboratories. It would be worthwhile to investigate the usefulness of stable isotope ratio measurements of Sr in the future.

  • use of stable isotope ratios for profiling of industrial Ephedrine samples application of hydrogen isotope ratios in combination with carbon and nitrogen
    Forensic Science International, 2009
    Co-Authors: Naoki Kurashima, Yasuteru Urano, Yukiko Makino, Kaori Sanuki, Yukari Ikehara, Tetsuo Nagano
    Abstract:

    Abstract The utility of hydrogen stable isotope ratio measurement by IR-MS for establishing the origin of Ephedrine and pseudoEphedrine (Ephedrines), precursors of methamphetamine, was evaluated. There are two kinds of commercial semisynthetic Ephedrines, one produced from molasses and the other from pyruvic acid. While the semisynthetic Ephedrines derived from pyruvic acid cannot be discriminated from biosynthetic Ephedrines and synthetic Ephedrines based on δ 13 C and δ 15 N values, they could be identified from the δ 2 H values. The low deuterium content of biosynthetic Ephedrines (δ 2 H: −193 to −151‰) allows a clear distinction from synthetic Ephedrines (δ 2 H: −73 to −30‰), semisynthetic Ephedrines derived from pyruvic acid (δ 2 H: +75 to +148‰) and semisynthetic Ephedrines derived from molasses (δ 2 H: −74 to +243‰). The wide range of δ 2 H values of semisynthetic Ephedrines is therefore very useful for the detailed classification of Ephedrines, in combination with the measurement of δ 13 C and δ 15 N values as described in our previous work. This study was carried out on a limited number of samples reflecting the various routes of Ephedrines manufacture. But it has become apparent that this stable-isotope analysis is an appropriate means by which to screen for manufacturing process of Ephedrines. This approach should be useful for worldwide precursor control of methamphetamine.

  • Evaluation of characteristic deuterium distributions of Ephedrines and methamphetamines by NMR spectroscopy for drug profiling.
    Analytical Chemistry, 2008
    Co-Authors: Teruki Matsumoto, Yasuteru Urano, Yukiko Makino, Ruri Kikura-hanajiri, Nobuo Kawahara, Yukihiro Goda, Tetsuo Nagano
    Abstract:

    We have established a method for quantitative analysis of the deuterium contents (D/H) at the phenyl, methine, benzyl, N-methyl and methyl groups of l-Ephedrine/HCl, d-pseudoEphedrine/HCl and methamphetamine/HCl by 2H NMR spectroscopy. Comparison of the 5 position-specific D/H values of l-Ephedrine/HCl and d-pseudoEphedrine/HCl prepared by three methods (chemical synthesis, semichemical synthesis, and biosynthesis) showed that chemically synthesized Ephedrines and semisynthetic Ephedrines have highly specific distributions of deuterium at the methine position and at the benzyl position, compared with the other positions. The classification of several methamphetamine samples seized in Japan in terms of the D/H values at these two positions clearly showed that the methamphetamine samples had been synthesized from Ephedrines extracted from Ephedra plants or semisynthetic Ephedrines but not from synthetic Ephedrine. This isotope ratio analysis method should be useful to trace the origins of seized methampheta...

  • determination of origin of Ephedrine used as precursor for illicit methamphetamine by carbon and nitrogen stable isotope ratio analysis
    Analytical Chemistry, 2004
    Co-Authors: Naoki Kurashima, Yasuteru Urano, Yukiko Makino, Setsuko Sekita, Tetsuo Nagano
    Abstract:

    The sale of Ephedrine, one of the precursors of methamphetamine, is strictly controlled and monitored in various countries to prevent the production of illicit methamphetamine. There are three kinds of production scheme for Ephedrine manufacture, and it is very useful for precursor control to investigate the origin of Ephedrine used for the synthesis of illicit methamphetamine. By means of stable isotope ratio mass spectrometry (IR-MS), we investigated the origin of Ephedrine based on the δ13C and δ15N values. The various origins of Ephedrine (biosynthetic, semisynthetic, or synthetic) could be discriminated clearly by using these values. The δ15N values of synthetic Ephedrine were more negative than those of Ephedrine from other sources. By the repeated distillation of methylamine in our laboratory, we confirmed that this could be due to isotope separation during distillation for the purification of methylamine used for Ephedrine synthesis. The values for Ephedrine used as the precursor were well-correla...

Yasuteru Urano - One of the best experts on this subject based on the ideXlab platform.

  • Trial analysis of drug profiling by liquid chromatography/mass spectrometry and inductively coupled plasma mass spectrometry to establish the origin of Ephedrines used as precursors for illicit production of methamphetamine.
    Rapid Communications in Mass Spectrometry, 2019
    Co-Authors: Yukiko Makino, Yasuteru Urano, Kiyoko Kaneko
    Abstract:

    Rationale We investigated whether chemical information on the origin of Ephedrine and pseudoEphedrine (Ephedrines) can be acquired by liquid chromatography/mass spectrometry (LC/MS) as a substitute method for stable isotope ratio mass spectrometry (IRMS), which is not routinely available in forensic laboratories. We examined the characteristic inorganic elemental contaminants of Ephedrines as a preliminary study. Methods The stable isotope ratios measured by IRMS analysis are expressed relative to the stable isotope ratios of conventional standards. Referring to the method using validated standard samples in IRMS, we selected a standard sample for acquiring stable isotopic ratio by LC/MS. The abundance ratio of the [M + 2H]+ ion to the [M + H]+ ion was measured by means of selected ion monitoring. We carried out qualitative analysis of inorganic elements contained in Ephedrines produced by different manufacturing methods with ICPMS. Results We found that the ratio of stable isotope ion to molecular ion (stable isotope ratio) of Ephedrines could be measured with LC/MS. The stable isotope ratio of Ephedrines determined by LC/MS were confirmed to show relatively good correlations with the carbon and hydrogen stable isotope ratios found by IR-MS. We identified strontium as a characteristic inorganic element contained in Ephedrines prepared by the semisynthetic method from molasses, or in the biosynthetic method from ephedra plants. Conclusions Our results suggest that useful chemical information can be obtained by LC/MS, which is easy to carry out, and is generally available in forensic laboratories. It would be worthwhile to investigate the usefulness of stable isotope ratio measurements of Sr in the future.

  • use of stable isotope ratios for profiling of industrial Ephedrine samples application of hydrogen isotope ratios in combination with carbon and nitrogen
    Forensic Science International, 2009
    Co-Authors: Naoki Kurashima, Yasuteru Urano, Yukiko Makino, Kaori Sanuki, Yukari Ikehara, Tetsuo Nagano
    Abstract:

    Abstract The utility of hydrogen stable isotope ratio measurement by IR-MS for establishing the origin of Ephedrine and pseudoEphedrine (Ephedrines), precursors of methamphetamine, was evaluated. There are two kinds of commercial semisynthetic Ephedrines, one produced from molasses and the other from pyruvic acid. While the semisynthetic Ephedrines derived from pyruvic acid cannot be discriminated from biosynthetic Ephedrines and synthetic Ephedrines based on δ 13 C and δ 15 N values, they could be identified from the δ 2 H values. The low deuterium content of biosynthetic Ephedrines (δ 2 H: −193 to −151‰) allows a clear distinction from synthetic Ephedrines (δ 2 H: −73 to −30‰), semisynthetic Ephedrines derived from pyruvic acid (δ 2 H: +75 to +148‰) and semisynthetic Ephedrines derived from molasses (δ 2 H: −74 to +243‰). The wide range of δ 2 H values of semisynthetic Ephedrines is therefore very useful for the detailed classification of Ephedrines, in combination with the measurement of δ 13 C and δ 15 N values as described in our previous work. This study was carried out on a limited number of samples reflecting the various routes of Ephedrines manufacture. But it has become apparent that this stable-isotope analysis is an appropriate means by which to screen for manufacturing process of Ephedrines. This approach should be useful for worldwide precursor control of methamphetamine.

  • Evaluation of characteristic deuterium distributions of Ephedrines and methamphetamines by NMR spectroscopy for drug profiling.
    Analytical Chemistry, 2008
    Co-Authors: Teruki Matsumoto, Yasuteru Urano, Yukiko Makino, Ruri Kikura-hanajiri, Nobuo Kawahara, Yukihiro Goda, Tetsuo Nagano
    Abstract:

    We have established a method for quantitative analysis of the deuterium contents (D/H) at the phenyl, methine, benzyl, N-methyl and methyl groups of l-Ephedrine/HCl, d-pseudoEphedrine/HCl and methamphetamine/HCl by 2H NMR spectroscopy. Comparison of the 5 position-specific D/H values of l-Ephedrine/HCl and d-pseudoEphedrine/HCl prepared by three methods (chemical synthesis, semichemical synthesis, and biosynthesis) showed that chemically synthesized Ephedrines and semisynthetic Ephedrines have highly specific distributions of deuterium at the methine position and at the benzyl position, compared with the other positions. The classification of several methamphetamine samples seized in Japan in terms of the D/H values at these two positions clearly showed that the methamphetamine samples had been synthesized from Ephedrines extracted from Ephedra plants or semisynthetic Ephedrines but not from synthetic Ephedrine. This isotope ratio analysis method should be useful to trace the origins of seized methampheta...

  • determination of origin of Ephedrine used as precursor for illicit methamphetamine by carbon and nitrogen stable isotope ratio analysis
    Analytical Chemistry, 2004
    Co-Authors: Naoki Kurashima, Yasuteru Urano, Yukiko Makino, Setsuko Sekita, Tetsuo Nagano
    Abstract:

    The sale of Ephedrine, one of the precursors of methamphetamine, is strictly controlled and monitored in various countries to prevent the production of illicit methamphetamine. There are three kinds of production scheme for Ephedrine manufacture, and it is very useful for precursor control to investigate the origin of Ephedrine used for the synthesis of illicit methamphetamine. By means of stable isotope ratio mass spectrometry (IR-MS), we investigated the origin of Ephedrine based on the δ13C and δ15N values. The various origins of Ephedrine (biosynthetic, semisynthetic, or synthetic) could be discriminated clearly by using these values. The δ15N values of synthetic Ephedrine were more negative than those of Ephedrine from other sources. By the repeated distillation of methylamine in our laboratory, we confirmed that this could be due to isotope separation during distillation for the purification of methylamine used for Ephedrine synthesis. The values for Ephedrine used as the precursor were well-correla...

Richard A. Glennon - One of the best experts on this subject based on the ideXlab platform.

  • in vitro characterization of Ephedrine related stereoisomers at biogenic amine transporters and the receptorome reveals selective actions as norepinephrine transporter substrates
    Journal of Pharmacology and Experimental Therapeutics, 2003
    Co-Authors: Richard B Rothman, Richard Young, John S Partilla, Bryan L Roth, Sandra J Hufeisen, Beth Ann Comptontoth, Jon Birkes, Richard A. Glennon
    Abstract:

    Ephedrine is a long-studied stimulant available both as a prescription and over-the-counter medication, as well as an ingredient in widely marketed herbal preparations, and is also used as a precursor for the illicit synthesis of methamphetamine. Ephedrine is related to phenylpropanolamine, a decongestant removed from the market place due to concerns that its use increased the risk of hemorrhagic stroke. Standard pharmacology texts emphasize that Ephedrine is both a direct and indirect adrenergic agonist, activating adrenergic receptors both by direct agonist activity as well as by releasing norepinephrine via a carrier-mediated exchange mechanism. Chemically, Ephedrine possesses two chiral centers. In the present study, we characterized the stereoisomers of Ephedrine and the closely related compounds pseudoEphedrine, norEphedrine, pseudonorEphedrine (cathine), methcathinone, and cathinone at biogenic amine transporters and a large battery of cloned human receptors (e.g., “receptorome”). The most potent actions of Ephedrine-type compounds were as substrates of the norepinephrine transporter (EC 50 values of about 50 nM) followed by substrate activity at the dopamine transporter. Screening the receptorome demonstrated weak affinity at α 2 -adrenergic and 5-hydroxytryptamine 7 receptors ( K i values 1–10 μM) and no significant activity at β-adrenergic or α 1 -adrenergic receptors. Viewed collectively, these data indicate that the pharmacological effects of Ephedrine-like phenylpropanolamines are likely mediated by norepinephrine release, and although sharing mechanistic similarities with, they differ in important respects from those of the phenylpropanonamines methcathinone and cathinone and the phenyisopropylamines methamphetamine and amphetamine.

  • Stimulus effects of phenylpropanolamine optical isomers in (+)amphetamine-trained rats.
    Pharmacology Biochemistry and Behavior, 2000
    Co-Authors: Richard Young, Richard A. Glennon
    Abstract:

    Abstract There are eight phenylpropanolamine optical isomers related in structure to the central stimulants methamphetamine and amphetamine. Some of these are quite well known, such as (−)Ephedrine, whereas others are relatively obscure, such as (−)cathine. Although certain of these phenylpropanolamines, such as (−)Ephedrine and (+)cathine, retain central stimulant activity and are about 10- to 25-fold less potent than (+)amphetamine, the eight phenylpropanolamines have been compared only once before in drug discrimination studies. This latter study employed (−)Ephedrine as the training drug. Because there are striking similarities between (−)Ephedrine and (+)amphetamine as training drugs, it was of interest to determine and compare the effect of all eight phenylpropanolamines in (+)amphetamine trained animals. Using rats trained to discriminate 1 mg/kg of (+)amphetamine from saline vehicle under a variable interval 15-s (VI 15-s) schedule of reinforcement, the (+)amphetamine stimulus generalized only to (−)Ephedrine (ED 50 = 4.5 mg/kg) and (+)cathine (ED 50 = 8.0 mg/kg), and both agents were at least 10 times less potent that (+)amphetamine (ED 50 = 0.37 mg/kg). These results stand in contrast to those obtained with the (−)Ephedrine-trained animals where the Ephedrine stimulus generalized to all of the phenylpropanolamines except for (−)pseudoEphedrine and (−)cathine. It is concluded that although there might be some similarity between the (−)Ephedrine and (+)amphetamine stimuli, there are clear differences between them as determined in tests of stimulus generalization under the conditions employed.

  • An examination of isomeric phenylpropanolamines in (-)Ephedrine-trained rats.
    Drug and Alcohol Dependence, 1999
    Co-Authors: Richard Young, Mikhail L. Bondarev, Richard A. Glennon
    Abstract:

    Abstract A total of eight isomeric phenylpropanolamines are possible when the terminal amine is either an N -monomethylamine or a primary amine: (−)Ephedrine, (+)Ephedrine, (+)pseudoEphedrine, (−)pseudoEphedrine, (−)norEphedrine, (+)norEphedrine, (+)cathine, and (−)cathine. Few previous studies have examined the individual optical isomers of these phenylpropanolamines and, with the exception of one report on locomotor effects, no comparative behavioral data have been published on this series of agents. Using rats trained to discriminate 4 mg/kg of (−)Ephedrine (i.p.) from saline vehicle using standard operant conditioning with a VI 15-s schedule of reinforcement, all eight agents were examined in tests of stimulus generalization. The (−)Ephedrine stimulus (ED 50 =0.90 mg/kg) generalized to (+)Ephedrine (ED 50 =2.64 mg/kg), (+)pseudoEphedrine (ED 50 =6.58 mg/kg), (−)norEphedrine (ED 50 =1.86 mg/kg), (+)norEphedrine (ED 50 =5.75 mg/kg), and (+)cathine (ED 50 =4.87 mg/kg). The (−)Ephedrine stimulus failed to generalize to either (−)pseudoEphedrine or (−)cathine; the latter agents produced a maximum of 29 and 31% (−)Ephedrine-appropriate responding, respectively. Thus, (a) six of the eight phenylpropanolamines produced Ephedrine-like stimulus effects, (b) (−)Ephedrine was the most potent of the examined agents, and (c) where stimulus generalization occurred, ED 50 values spanned less than a tenfold range.

Naoki Kurashima - One of the best experts on this subject based on the ideXlab platform.

  • use of stable isotope ratios for profiling of industrial Ephedrine samples application of hydrogen isotope ratios in combination with carbon and nitrogen
    Forensic Science International, 2009
    Co-Authors: Naoki Kurashima, Yasuteru Urano, Yukiko Makino, Kaori Sanuki, Yukari Ikehara, Tetsuo Nagano
    Abstract:

    Abstract The utility of hydrogen stable isotope ratio measurement by IR-MS for establishing the origin of Ephedrine and pseudoEphedrine (Ephedrines), precursors of methamphetamine, was evaluated. There are two kinds of commercial semisynthetic Ephedrines, one produced from molasses and the other from pyruvic acid. While the semisynthetic Ephedrines derived from pyruvic acid cannot be discriminated from biosynthetic Ephedrines and synthetic Ephedrines based on δ 13 C and δ 15 N values, they could be identified from the δ 2 H values. The low deuterium content of biosynthetic Ephedrines (δ 2 H: −193 to −151‰) allows a clear distinction from synthetic Ephedrines (δ 2 H: −73 to −30‰), semisynthetic Ephedrines derived from pyruvic acid (δ 2 H: +75 to +148‰) and semisynthetic Ephedrines derived from molasses (δ 2 H: −74 to +243‰). The wide range of δ 2 H values of semisynthetic Ephedrines is therefore very useful for the detailed classification of Ephedrines, in combination with the measurement of δ 13 C and δ 15 N values as described in our previous work. This study was carried out on a limited number of samples reflecting the various routes of Ephedrines manufacture. But it has become apparent that this stable-isotope analysis is an appropriate means by which to screen for manufacturing process of Ephedrines. This approach should be useful for worldwide precursor control of methamphetamine.

  • determination of origin of Ephedrine used as precursor for illicit methamphetamine by carbon and nitrogen stable isotope ratio analysis
    Analytical Chemistry, 2004
    Co-Authors: Naoki Kurashima, Yasuteru Urano, Yukiko Makino, Setsuko Sekita, Tetsuo Nagano
    Abstract:

    The sale of Ephedrine, one of the precursors of methamphetamine, is strictly controlled and monitored in various countries to prevent the production of illicit methamphetamine. There are three kinds of production scheme for Ephedrine manufacture, and it is very useful for precursor control to investigate the origin of Ephedrine used for the synthesis of illicit methamphetamine. By means of stable isotope ratio mass spectrometry (IR-MS), we investigated the origin of Ephedrine based on the δ13C and δ15N values. The various origins of Ephedrine (biosynthetic, semisynthetic, or synthetic) could be discriminated clearly by using these values. The δ15N values of synthetic Ephedrine were more negative than those of Ephedrine from other sources. By the repeated distillation of methylamine in our laboratory, we confirmed that this could be due to isotope separation during distillation for the purification of methylamine used for Ephedrine synthesis. The values for Ephedrine used as the precursor were well-correla...