Features of extracting phenol and 4-methylphenol from aqueous solutions

Phenol and 4-methylphenol were extracted from aqueous solutions by 5 organic solvents. The degree of extraction depended on such factors as type of extracting agent, pH of aqueous phase, and water saturation of extracting agent. The necessary number of extractions for obtaining the preset volumes of studied compounds is calculated.     

Synthesis of 4-methyl-5-arylpyrimidines and 4-arylpyrimidines: route specific markers for the Leuckardt preparation of amphetamine, 4-methoxyamphetamine, and 4-methylthioamphetamine

General synthetic routes to 4-methyl-5-arylpyrimidines and 5-arylpyrimidines are described. 4-Benzylpyrimidine, 4-methyl-5-phenylpyrimidine, 4-(4-methoxybenzyl)pyrimidine, and 4-methyl-5-(4-methoxyphenyl)pyrimidine have been positively identified as route-specific by-products in the Leuckardt preparations of amphetamine and 4-methoxyamphetamine.Using headspace solid phase microextraction (SPME) 4-(4-methoxybenzyl)pyrimidine and 4-methyl-5-(4-methoxyphenyl)pyrimidine have been identified in illicit tablets containing 4-methoxyamphetamine. This is an indication that illicit laboratories use the Leuckardt method for the preparation of 4-methoxyamphetamine.Flatliner tablets containing 4-methylthioamphetamine have been screened for the presence of 4-(4-methylthiobenzyl)pyrimidine and 4-methyl-5-(4-methylthiophenyl)pyrimidine using both headspace and aqueous phase SPME. As these pyrimidines were not detected it would appear likely that illicit laboratories are not using the Leuckardt method for the preparation of 4-methylthioamphetamine.     

Identification of common impurities present in the synthetic routes leading to 4-methylthioamphetamine (4-MTA). Part II: Reductive amination and nitropropene route

In this paper the by-products arising during the synthesis of 4-methylthioamphetamine (4-MTA) by LiAlH(4) reduction of 1-(4-methylthiophenyl)-2-nitropropene (nitropropene route) and reductive amination of 4-methylthiophenyl-2-propanone in the presence of NaCNBH(4) are investigated. The identification of 4-methylthio derivatives of N-(β-phenylisopropyl)benzaldimine, 4-methylthio derivative of N-(β-phenylisopropyl)benzyl methyl ketimine, 1-(4-methylthiophenyl)-N-(4-methylthiobenzyl)-2-propanamine, (RS) and (SS/RR)-N,N-di-[β-(4-methylthiophenyl)isopropyl]amine, 4-methylthiobenzyl ether and methylthiobenzoic acid methyl ester as most prominent impurities in crude 4-MTA synthesised by reductive amination of 4-methylthiophenyl-2-propanone, is reported. Methylthio derivatives of 2-methyl-3-phenylaziridine, 2-benzylaziridine, and 4-methylthio derivative of BMK oxime as route-specific markers of nitropropene route leading to 4-MTA, were also characterized. The identity of these compounds was confirmed by their independent synthesis.     

Degradation pathways of 4-methylmethcathinone in alkaline solution and stability of methcathinone analogs in various pH solutions

Analogs of methcathinone (MC), a psychoactive stimulant, are in circulation all over the world. These analogs have been assumed to be unstable in alkaline solutions, as is MC itself. The aims of this study were: (i) to identify the degradation products of 4-methylmethcathinone (4-MMC), a typical MC analog, in solution at pH 12 and to determine the degradation pathway, (ii) to investigate the effects of antioxidants such as l-ascorbic acid and sodium sulfite on the degradation of 4-MMC, and (iii) to investigate the stability of seven MC analogs (4-MMC, 4-, 3-, or 2-fluoromethcathinone, 4-methoxymethcathinone, N-ethylcathinone, and N,N-dimethylcathinone) in solutions at different pHs.1-(4-Methylphenyl)-1,2-propanedione (MPPD), 4-methylbenzoic acid (MBA), N,4-dimethylbenzamide (DMBA), and N-acetyl-4-MMC (N-Ac-4-MMC) were identified as the degradation products of 4-MMC in pH 12 solution by gas chromatography-mass spectrometry. There are two degradation pathways for 4-MMC as follows: (a) 4-MMC→MPPD→MBA→DMBA and (b) 4-MMC→N-Ac-4-MMC. Oxidants such as dissolved oxygen were presumed to be involved in this degradation based on the suppressive effects generated by the addition of antioxidants. All of the seven MC analogs tested were stable in acidic (pH 4) solution but degraded in neutral-to-basic solutions. Their degradation rates increased with increasing pH, and varied with their chemical structures. These findings will be very useful for not only forensic analysis but also future pharmacokinetic analysis.     

Identification and synthesis of by-products found in 4-methylthioamphetamine (4-MTA) produced by the Leuckart method

The synthesis of the designer drug 4-methylthioamphetamine (4-MTA) has been carried out using the well-known Leuckart reaction in four versions. The treatment of 4-methylthiophenylacetone with formamide, mixture of formamide/formic acid, ammonium formate, and mixture of ammonium formate and formic acid followed by acid hydrolysis brought about the formation of 4-MTA contaminated with a number of impurities. The gas chromatography mass-spectrometry (GC-MS) analysis of the reaction mixtures allowed identification of the most prominent impurities, such as diasteromers of N,N-di-[β-(4-methylthiophenyl)isopropyl]amine, N,N-di-[β-(4-methylthiophenyl)isopropyl]methylamine, N,N-di-[β-(4-methylthiophenyl)isopropyl]formamide, the Schiff bases derived from 4-MTA and 4-methylbenzaldehyde (benzaldimine) and 4-methylthiophenylacetone (ketimine) as well as some heterocycles: 4-methyl-5-(4'-methylthiophenyl)pyrimidine, 4-(4'-methylthiobenzyl)pyrimidine, 2,6-dimethyl-3,5-di-(4'-methylthiophenyl)pyridine, 2,4-dimethyl-3,5-di-(4'-methylthiophenyl)pyridine. The correctness of identification was confirmed by independent synthesis of these compounds. Each synthesized reference compound was characterized by means of MS, (1)H and (13)C NMR, and IR methods. The stereochemistry of (RR/SS) diasteromer of N,N-di-[β-(4-methylthiophenyl)isopropyl]amine was confirmed by a crystallographic method.     

The analytical profile of some 4-methylthioamphetamine (4-MTA) homologues

The 4-methylthioamphetamine (4-MTA) is a sulphur-containing amphetamine-type stimulant (ATS), which appeared on the illicit market in Europe at the end of 90s. For the purpose of this study, several N-alkyl homologues of 4-MTA, including 4-methylthiomethamphetamine (4-MTMA), 4-methylthioethylamphetamine (4-MTEA), 4-methylthiodimethamphetamine (4-MTDMA), 4-methylthiopropylamphetamine (4-MTPA) and 4-methylthiobutylamphetamine (4-MTBA) were synthesized. The homologues were characterized by means of gas chromatography/mass spectrometry (GC–MS), infrared (IR) spectroscopy and the magnetic resonance spectroscopy (¹H and ¹³C NMR). The gas chromatography and mass spectrometry properties of their acetyl, trifluoroacyl (TFA), pentafluoropropionyl (PFP) and heptafluorobutyryl (HFB) derivatives were also investigated and discussed.     

过敏性休克死亡机体内白三烯变化的研究

本研究采用反相洗脱高效液相色谱(HPLC)法检测青霉素和血清过敏休克致死机体中自三烯(Leukotrienes,LTs)。(1)过敏休克前血中未检出LTs的任一组分,休克死亡后检出LTB_4和LTD_4。青霉素过敏血中LTB_4含量是10.10±4.76(ng/ml),LTD_4是26.75±6.55(ng/ml),未检出LTC_4和LTF_4。(2)正常动物肺,脾和肾中均未检出LTs。过敏休克的肺,脾和肾中不仅检出LTB_4和LTD_4,而且在不同脏器中呈规律分布。青霉素过敏肺中LTs_4是23.75±3.80(ng/g),LTD4是58.58±11.39(ng/g))未检出LTC_4和LTE_4。脾中仅有LTB_424.36±3.62(ng/g)。肾中仅有LTD_12.17±2.55(ng/g)。(3)过敏休克致死机体置室温6或12h,或置冰箱48h再测LTs,未见明显变化。(4)青霉素和血清诱发的过敏休克中,LTs的增加和分布是一致的。本研究提示:LTs含量和分布的变化是过敏性休克所共有,可为过敏性休克急死的法医学死因检定提供有价值的证据。     

Identification and synthesis of some contaminants present in 4-methoxyamphetamine (PMA) prepared by the Leuckart method

The clandestine synthesis of ring and side chain modified phenylisopropylamines continues to be a major source of these drugs of abuse. One method used for the synthesis of the amphetamine and related compounds involves the treatment of the appropriate ketone with formamide or ammonium formate followed by acid hydrolysis of intermediate N-formyl derivative. In this paper the synthesis of 4-methoxyamphetamine (PMA, 1) by the Leuckart method is investigated. The identification by means of gas chromatography-mass spectrometry (GC-MS) of methoxy derivative of N-(beta-phenylisopropyl)benzaldimine 9, methoxy derivative of N-(beta-phenylisopropyl)benzyl methyl ketimine 5, 1-(4-methoxyphenyl)-N-(4-methoxybenzyl)-2-propanamine 10, (RR/SS) and (RS) 1-(4-methoxyphenyl)-N-[2-(4-methoxyphenyl)-1-methylethyl]-2-propanamine 6a-6c, (RR/SS) and (RS)-1-(4-methoxyphenyl)-N-methyl-N-[2-(4-methoxyphenyl)-1-methylethyl]-2-propanamine 7a-7c, (RR/SS) and (RS)-1-(4-methoxyphenyl)-N-formyl-N-[2-(4-methoxyphenyl)-1-methylethyl]-2-propanamine 8a-8c in crude PMA, are reported. The identity of these compounds was confirmed by independent synthesis of reference compounds. The NMR, MS, IR data, stereochemistry and some chromatographic properties of synthesized compounds are discussed. Finally, the results of the GC-MS analysis of illicitly prepared tablets, containing PMA 1 and 4-methoxymethamphetamine (PMMA, 2), are outlined. The presence of 4-methoxydimethylamphetamine 11, 4-methoxyethylamphetamine 12, and 4-hydroxymethamphetamine 13 are reported in these tablets. The identity of 2, 11, and 12 was confirmed by their independent synthesis.     

Anise oil as para-methoxyamphetamine (PMA) precursor

These days, MDMA is one of the most popular drugs of abuse. Due to its illegality, MDMA and its chemical precursors are watched by governmental organizations in many countries. To avoid conflicts with legal instances, underground chemists have tried to market several new unregulated amphetamine analogues, such as 4-MTA. Para-methoxyamphetamine (PMA), on the other hand, is regulated by law but its precursors are easily obtained since they are cheap and unwatched. This article presents such a case, namely the large scale synthesis of PMA using anethole, a main constituent of anise oil, as precursor. Anethole has been converted to its phenyl acetone analogue via peracid oxidation, while PMA itself has been synthesized using this ketone as precursor in the Leuckart synthesis. The synthesis of PMA using anethole as starting product has been investigated applying GC/MS and GC-HSPME/MS techniques, hereby discovering new specific (4-methoxyphenol) and already identified synthesis impurities (4-methyl-5-(4-methoxyphenyl)pyrimidine, N-(beta-4-methoxyphenylisopropyl)-4-methoxybenzyl methyl ketimine, 1-(4-methoxyphenyl)-N-(2-(4-methoxyphenyl)-1-methylethyl-2-propanamine, 1-(4-methoxyphenyl)-N-methyl-N-(2-(4-methoxyphenyl)-1-methylethyl-2-propanamine, N-(beta-4-methoxyphenylisopropyl)-4-methoxybenzaldimine). The new impurity 4-methoxyphenol is specific for the application of a peracid oxidation method where anethole is used as precursor.     

Oligonucleotide fingerprinting using (GTG)5 and (GACA)4 probes for the differentiation of body fragments

For the detection of postmortem stability of DNA and for the identification of parts of dead bodies of unknown origin the oligonucleotide probes (GTG)5 and (GACA)4 can be used. (GTG)5 is a highly discriminating probe which allows to differentiate in the 4 to 25 kilobase range of DNA fragments. DNA fingerprints obtained by (GACA)4 show useful results especially in the short fragment range. The (GACA)4 probe can therefore be used to analyze partially degraded DNA.     

Application of solid-phase microextraction to the profiling of an illicit drug: manufacturing impurities in illicit 4-methoxyamphetamine

This article describes the application of solid-phase microextraction (SPME) to the recovery of manufacturing by-products and impurities from an illicit drug seizure. The preparation chosen for examination using this technique contained 4-methoxyamphetamine, an hallucinogenic amphetamine that has been encountered frequently in South Australia. Compounds found in the PMA preparation included 4-methoxyphenol, 4-methoxybenzaldehyde, 4-methoxyphenyl-2-propanone, 4-methoxyphenyl-2-propanol, 4-methoxyphenyl-propene, and (tentatively) 4-methyl-5-(4'-methoxyphenyl) pyrimidine. The presence of these compounds suggests that the active drug was prepared from 4-methoxybenzaldehyde via 4-methoxyphenyl-2-propanone using a Leuckardt reductive amination. In this instance, SPME was found to be a simple, rapid, and non-destructive recovery technique that gave results complementary to those provided by conventional liquid-liquid extraction. There is an indication that SPME might find application in profiling of illicit drugs.     

Synthesis of standards of the most important markers of Leuckart p-methoxymethamphetamine (PMMA). Examination of the influence of experimental conditions and a drug diluent on SPE/TLC profiling

The synthesis of characteristic markers of PMMA obtained by Leuckart method was described. The effectiveness of a procedure of SPE/TLC screening profiling of impurities was studied on the basis of selected impurities. The influence of glucose (a drug diluent) on the profile quality was investigated. The intermediate product (characteristic for the Leuckart synthesis) N-formyl-p-methoxymethamphetamine (1) and by-products: N-formyl-p-methoxyamphetamine (2), p-methoxyamphetamine (3), N,N-dimethyl-p-methoxyamphetamine (4), (RS) and (RR/SS) diastereoisomers of bis(1-methyl-2-(4-methoxyphenyl)ethyl)amine (meso-5 and rac-5), (RS) and (RR/SS) diastereoisomers of N-methyl-bis(1-methyl-2-(4-methoxyphenyl)ethyl)amine (meso-6 and rac-6), N-methyl-1,3-bis(4-methoxyphenyl)propane-2-amine (7) were synthesized. The substrate p-methoxyphenylacetone and the impurities 1 and 4 were used in the study of influence of experimental conditions and glucose on the profiling process and results. The experiments were carried out according to a 2(4) factorial design. The proposed criterions of the profile quality are based on matrix presentation of TLC patterns. They take into account the number of spots revealed, differences between R(f) values and intensity of fluorescence, simultaneously.     

Identification of 2‐(ethylamino)‐1‐(4‐methylphenyl)‐1‐pentanone (4‐MEAP), a New “Legal High” Sold by an Internet Vendor as 4‐Methyl Pentedrone

Online vendors are offering a new legal high, 4‐methylpentedrone (4‐MPD). Information for potential users provided by internet vendors of 4‐MPD includes incorrect structures and nonexistent CAS numbers. A sample of 4‐MPD was obtained and analyzed using GC‐MS, NMR, and LC‐EIS. The fragmentation data from the GC‐MS and LC‐EIS produced an M‐1 ion that suggested the molecular mass was 219 amu, rather than 205 amu as calculated for 4‐methylpentedrone. The difference in molecular mass corresponded to the addition of a methyl group. Based on the mass and fragmentation pattern, two standards were synthesized, 2‐(ethylamino)‐1‐(4‐methylphenyl)‐1‐pentanone and 1‐(4‐methylphenyl)‐2‐(propylamino)‐1‐butanone. The synthesis involved bromination of the appropriate ketone followed by the reaction with ethylamine or propylamine. Based on the NMR data and unique fragmentation patterns produced by these molecules, the sample was identified as 2‐(ethylamino)‐1‐(4‐methylphenyl)‐1‐pentanone, not 4‐methylpentedrone.     

Results of the GEP-ISFG collaborative study on two Y-STRs tetraplexes: GEPY I (DYS461, GATA C4, DYS437 and DYS438) and GEPY II (DYS460, GATA A10, GATA H4 and DYS439)

A collaborative exercise was carried out by the Spanish and Portuguese ISFG Working Group (GEP-ISFG) in order to evaluate the performance of two Y-chromosome STR PCR tetraplexes, which include the loci DYS461, GATA C4, DYS437 and DYS438 (GEPY I), and DYS460, GATA A10, GATA H4 and DYS439 (GEPY II). The participating laboratories were asked to type three samples for the eight markers, using a specific amplification protocol. In addition, two control samples, with known haplotypes, were provided. The results obtained by the 13 different participating laboratories were identical, except for two laboratories that failed to type correctly the same two samples for GATA C4. By sequence analyses, two different GATA C4 allele structures were found. One control sample (allele 21) and two questioned samples (allele 22, correctly typed by all the laboratories, and allele 25) presented the following repeat structure: (TCTA)4(TGTA)2(TCTA)2(TGTA)2(TCTA)n, but different from the one found for allele 26 in one sample included in this exercise, as well as in the second control sample (allele 23), namely (TCTA)4(TGTA)2(TCTA)2(TGTA)2(TCTA)2(TGTA)2(TCTA)n. The collaborative exercise results proved that both Y-tetraplexes produce good amplification results, with the advantage of being efficiently typed using different separation and detection methodologies. However, since GATA C4 repeat presents a complex structure, with alleles differing in sequence structure, efficient denaturing conditions should be followed in order to avoid typing errors due to sizing problems.     

气相色谱质谱联用法检测大鼠尿液中2C-B及其代谢物

目的研究4-溴-2,5-二甲氧基苯乙胺（2C—B）在大鼠体内的代谢物以及代谢途径。方法取Wistar大鼠3只,以2C-B灌胃,收集24h内尿液,用B葡萄糖醛酸酶水解,Oasis HLB柱固相提取,DB-35MS柱分析,气相色谱质谱联用检测。结果从大鼠尿液中检出6种2C-B的代谢产物,分别为：4-溴-2-羟基-5-甲氧基苯乙醇、4-溴-2,5-二甲氧基苯乙醇、4-溴-2-羟基-5-甲氧基苯乙酸、4-溴-2,5-二甲氧基苯乙酸、1-乙酰氨基-2-（4-溴-5-羟基-2-甲氧基苯）乙烷和1-乙酰氨基-2-（4-溴-2-羟基-5-甲氧基苯）乙烷。未检出2C—B原药。结论2C-B在大鼠尿液中主要以代谢物形式存在,其在大鼠体内至少仔在两种代谢途径：第一种是2C—B的2位和5位氧上去甲基后氨基被乙酰化;第二种是2C—B去氨基生成醛,接着被还原或氧化生成醇和羧酸。     

The potential of urinary androstdiene markers to identify 4-androstenediol (4-ADIOL) administration in athletes

Doping control laboratories accredited by the World Anti-Doping Agency (WADA) require criteria that allow endogenous steroids to be distinguished from their synthetic analogues in urine. Methodology based on "looking outside the metabolic box" was used in this study to identify diagnostic urinary markers of 4-androstenediol (4-ADIOL) administration. Androst-2,4-diene-17-one and androst-3,5-diene-17-one are proposed to be formed in urine from acid-catalyzed hydrolysis of 4-ADIOL sulfoconjugate, a major phase II metabolic product of 4-ADIOL. The presence of these markers in the routine gas chromatography-mass spectrometry (GC-MS) steroid screen was suitable to identify samples requiring confirmation by gas chromatography-combustion-isotope ratio mass spectrometry (GC-C-IRMS) - to measure the carbon isotope ratio (δ(13)C) of the androstdiene markers and confirm their likely synthetic origin based on depleted (13)C content.     

ABO genotyping by duplex amplification and oligonucleotide arrays assay

Objective

Research on the application feasibility of ABO genotyping for forensic identification by oligonucleotide arrays assay.

Methods

Oligonucleotide microarrays which detect three different SNPs in exon 6 and exon 7 for ABO genotyping were used. After hybridization wash, the arrays were scanned and fluorescence intensities were analyzed using microarray population studies on ABO was carried out in a sample of 115 unrelated Chinese Han individuals oligonucleotide arrays for genotype detection. The method was also applied to cases.

Results

Technique could identify six genotypes of ABO system and the results of GeneChip analyses confirmed by PCR–RFLP. According to the results of population studies, no significant deviations Hardy–Weinberg equilibrium could be found. The observed heterozygosity (H-obs) was 0.591. Expected heterozygosity (H-exp) was 0.616. The polymorphic information content (PIC) was the average exclusion probability in paternity testing for duos (PE (1)) was 0.188. The average exclusion probability in paternity testing for trios (PE(2)) was 0.344. The discrimination power 0.777.

Conclusion

The data and case application demonstrated that ABO typing by oligonucleotide probe arrays was a useful technique for paternity testing and individual identification.     

Psychopathic traits and offending trajectories from early adolescence to adulthood

Purpose

Measures of adolescent psychopathy have yet to be examined in offending trajectory studies. This may explain why identifying etiological differences between individuals following high-rate and moderate-rate offending trajectories has remained elusive. The current study used the Psychopathy Checklist: Youth Version (PCL:YV) to examine psychopathic traits and offending trajectories within a sample of incarcerated offenders.

Methods

Convictions were measured for Canadian male (n = 243) and female (n = 64) offenders at each year between ages 12 and 28. Semi-parametric group based modeling identified four unique trajectories: adolescence-limited (AL) (27.3% of sample), explosive-onset fast desister (EOFD) (30.6%), high-rate slow desister (HRSD) (14.6%), and high frequency chronic (HFC) (27.5%).

Findings

Both a three and a four factor model of psychopathy were tested, and both factor structures were positively and significantly associated with the HRSD and HFC trajectories. Regarding individual factors of psychopathy, the ‘Antisocial’ factor of the PCL:YV was the only individual dimension significantly associated with membership in high-rate compared to moderate-rate offending trajectories.

Conclusions

Psychopathic traits appear more commonly present amongst individuals who follow chronic versus moderate offending trajectories. Implications for early intervention and risk management of offenders are discussed.     

Mind your manners: quality of manner of death certification among medical examiners and coroners in Taiwan

To assess the quality of manner of death (MOD) certification among medical examiners/coroners (ME/Cs) in Taiwan, death certificates issued in 2002 for which the final MOD was suicide or undetermined were extracted for analysis. Indicators of the quality of MOD certification included (1) MOD not given by the ME/Cs; (2) MOD assigned by the ME/Cs was changed by the coder; (3) ratio between undetermined and suicide deaths (U/S ratio). There were 450 death certificates for which the ME/Cs did not assign the MOD in the original certificate. Three fifths (285/450) of them were issued by 4 ME/Cs. The same 4 ME/Cs also had extremely high U/S ratios (1.25-1.84) compared with the average (0.31). The overall quality of MOD certification among ME/Cs in Taiwan was fair; only a small number of ME/Cs had poor quality in MOD certification. The high U/S ratio among the 4 ME/Cs would certainly affect the suicide mortality rates of the counties the 4 ME/Cs were in charge of. Actions should be taken to improve the certification quality of these 4 ME/Cs.     

Chemical identification and optimization of the 4-aminophenol colorimetric test for the differentiation between hemp-type and marijuana-type cannabis plant samples

The 4- Aminophenol (4-AP) colorimetric test is a fast, easy-to-use, and cost-effective presumptive assay of cannabis plant material producing different chromophores with THC-rich cannabis (blue color) and with CBD-rich cannabis (pink color). The main drawback of the 4-AP test is a brief observation window where the color rapidly changes to black, limiting the utility of the test. We now report for the first time, the identification of the product chromophores between 4-AP and CBD/THC as well as propose an explanation and a solution for the color degradation of the chromophores. The identification of the chromophores is provided by spectroscopic (UV–Vis), chromatography, and mass spectrometry (TLC and LC-QToF-MS). Oxidation of excess 4-AP (Reagent A) in the presence of NaOH (Reagent B) produces the black color observed for the previously reported 4-AP tests and reported in the literature. The adjustment of reactants concentrations and volumes of 4-AP:THC/CBD to a 1:1 ratio significantly reduces the black oxidation by-product and increases the observation window up to 2 h instead of the previously reported 5–10 min. For the first time, mass spectrometry and chromatography confirmed that the reaction of THC and CBD with 4-AP produced chromophores with m/z (M + H) = 420, consistent with proposed indophenol structures. The TLC method developed confirmed the separation between CBD and THC chromophores. The specificity of the test is also reported, showing false positive results for the presence of THC (blue color) for samples of thyme and oregano. LDA and SIMCA models showed that the optimized 4-AP procedure performs better than the previously reported 4-AP color test.