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1.
J Anal Toxicol ; 44(1): 92-102, 2020 Jan 07.
Artigo em Inglês | MEDLINE | ID: mdl-31436798

RESUMO

The production and consumption of new psychoactive substances (NPSs) has been raising a major concern worldwide. Due to easy access and available information, many NPSs continue to be synthesized with an alarming increase of those available to purchase, despite all the control efforts created. A new analytical method was developed and validated to determine a group of phenethylamines and synthetic cathinones: cathinone, flephedrone, buphedrone, 4-MTA, α-PVP, methylone, 2C-P, ethylone, pentylone, MDPV and bromo-dragonFLY in whole blood. A mixed-mode solid phase extraction was applied to 250 µL of sample, and the extracts were derivatized with fast microwave technique before being analyzed by gas chromatography-mass spectrometry (GC-MS). The validation procedure followed the Scientific Working Group for Forensic Toxicology (SWGTOX) guidelines with parameters that included selectivity, linearity, limits of detection and quantification, intra- and inter-day precision and accuracy, recoveries and stability. The method presented linearity between 5 and 500 ng/mL for cathinone, buphedrone, 4-MTA, methylone, 2C-P and bromo-dragonFLY, 10-500 ng/mL for flephedrone, ethylone, pentylone and MDPV, and 40-500 ng/mL for α-PVP, with determination coefficients above 0.99 for all analytes. Recoveries ranged between 70.3% and 116.6%, and regarding intra- and inter-day precision, the relative mean errors were typically lower than 8.6%. The method was successfully applied to over 100 authentic samples from the Laboratory of Chemistry and Forensic Toxicology, Centre Branch, of the National Institute of Legal Medicine and Forensic Sciences, Portugal.


Assuntos
Drogas Desenhadas/metabolismo , Toxicologia Forense , Micro-Ondas , Psicotrópicos/sangue , Detecção do Abuso de Substâncias/métodos , Acetona/análogos & derivados , Acetona/análise , Acetona/sangue , Alcaloides/análise , Alcaloides/sangue , Anfetaminas/análise , Anfetaminas/sangue , Drogas Desenhadas/análise , Etilaminas/análise , Etilaminas/sangue , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Limite de Detecção , Metanfetamina/análogos & derivados , Metanfetamina/análise , Metanfetamina/sangue , Pentanonas/análise , Pentanonas/sangue , Fenetilaminas/análise , Fenetilaminas/sangue , Pirrolidinas/análise , Pirrolidinas/sangue
2.
Eur J Med Chem ; 183: 111689, 2019 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-31541871

RESUMO

A series of ß-azole-phenylacetone derivatives with novel structures were designed and synthesized to combat the increasing incidence of susceptible fungal infections and drug-resistant fungal infections. The antifungal activity of the synthesized compounds was assessed against five susceptible strains and five fluconazole-resistant strains. Antifungal activity tests showed that most of the compounds exhibited excellent antifungal activities against five pathogenic strains with MIC values in the range of 0.03-1 µg/mL. Compounds with R1 = 3-F substituted and 15o and 15ae exhibited moderate antifungal activities against fluconazole-resistant strains 17# and CaR with MIC values in the range of 1-8 µg/mL. Compounds with R1 = H or 2-F (such as 15a, 15o, 15p) displayed moderate to good antifungal activity against fluconazole-resistant strains 632, 901 and 904 with MIC values in the range of 0.125-4 µg/mL. Notably, 15o and 15ae exhibited antifungal activity against five susceptible strains and five fluconazole-resistant strains. Preliminary mechanistic studies showed that the potent antifungal activity of compound 15ae stemmed from inhibition of C. albicans CYP51. Compounds 15o, 15z and 15ae were nearly nontoxic to mammalian A549 cells.


Assuntos
Acetona/análogos & derivados , Antifúngicos/farmacologia , Azóis/farmacologia , Candida albicans/efeitos dos fármacos , Farmacorresistência Fúngica/efeitos dos fármacos , Fluconazol/farmacologia , Células A549 , Acetona/química , Acetona/farmacologia , Antifúngicos/síntese química , Antifúngicos/química , Azóis/química , Relação Dose-Resposta a Droga , Fluconazol/química , Humanos , Testes de Sensibilidade Microbiana , Estrutura Molecular , Relação Estrutura-Atividade
4.
Food Chem ; 287: 265-272, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-30857698

RESUMO

In this study, the degradation of tropane alkaloids in pasta under boiling (100 °C during 10 min) and tea making (100 °C and let cool 5 min) conditions has been evaluated for the first time. Pasta and green tea were contaminated with Datura Stramonium and Brugmansia Arborea seeds (pasta and green tea), whereas coca leaf tea was directly analysed. The compounds were extracted using solid-liquid extraction coupled to a preconcentration stage (only for the cooking water), and the compounds were analysed by liquid chromatography coupled to mass spectrometry (Exactive-Orbitrap analyser). Degradation studies indicate that concentration of tropane alkaloids decreases, and it depends on the compound, observing the highest degradation for tropinone, tropane, cuscohygrine and tropine, as well as it was observed that compounds migrated to the aqueous phase during cooking step. Finally, post-targeted analysis was performed and other tropane alkaloids were found, as scopine, tigloidine or convolvine, showing a similar behaviour under cooking conditions.


Assuntos
Coca , Contaminação de Alimentos , Solanaceae , Chá/química , Tropanos/química , Acetona/análogos & derivados , Acetona/química , Cromatografia Líquida , Datura stramonium , Fagopyrum , Espectrometria de Massas , Folhas de Planta , Pirrolidinas/química , Sementes , Extração em Fase Sólida , Temperatura de Transição
5.
Forensic Sci Int ; 297: 171-176, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30798102

RESUMO

BACKGROUND: Hair analysis is a suitable way to discriminate between coca chewers and consumers of manufactured cocaine using the coca alkaloids hygrine (HYG) and cuscohygrine (CUS) as markers. In the present preliminary study it was examined whether CUS and HYG can be detected in hair of occasional and moderate coca chewers or coca tea drinkers, whether CUS and HYG appear in hair of PACO consumers (smoking coca paste waste), and whether anhydroecgonine methyl ester (AEME) is a useful cocaine smoking marker in this context. METHOD: Three groups were included: 10 volunteers from Buenos Aires with occasional or moderate chewing of coca leaves or drinking coca tea, 20 Argentinean PACO smokers and 8 German cocaine users. The hair samples (1-4 segments) were analyzed by a validated LC-MS/MS method for cocaine (COC), norcocaine (NC), benzoylecgonine (BE), ecgonine methyl ester (EME), cocaethylene (CE), cinnamoylcocaine (CIN), tropacocaine (TRO), AEME, CUS and HYG. For comparison, eight samples of coca leaves or coca tea were analyzed. RESULTS: Only low concentrations of COC were found in hair of seven occasional users of coca leaves or coca tea (0.010-0.051 ng/mg). For three moderate chewers of coca leaves all compounds were detected including AEME but except TRO. The hair samples of PACO smokers contained much higher concentrations of COC (0.027-341 ng/mg, mean 37.4 ng/mg) and its metabolites. CUS was not found in these samples but traces of HYG were seen in 8 of 37 hair segments. AEME as a marker for coca smoking was detected in hair of 15 smokers. In comparison to COC, the concentrations of EME and CIN were higher for PACO smokers than for German cocaine consumers. AEME (56 ± 20 µg/g) was detected in all coca leave and coca tea samples which explains the detection of this substance in hair of coca chewers. Therefore, its use for differentiation between coca chewers and PACO smokers is limited. CONCLUSION: CUS remains to be the most suitable marker in hair for chewing coca leaves or drinking coca tea more frequently than two times per month since it does not appear in hair of Argentinean PACO smokers and German cocaine users. Contrary to a previous proposal, the ratios CIN/COC and EME/COC appeared not to be applicable as criteria for this purpose because of the higher concentration of these alkaloids in hair of PACO smokers. More research is needed to assess the value of AEME in hair of South American coca leave or cocaine users.


Assuntos
Coca , Transtornos Relacionados ao Uso de Cocaína/diagnóstico , Cabelo/química , Detecção do Abuso de Substâncias/métodos , Acetona/análogos & derivados , Acetona/análise , Adolescente , Adulto , Biomarcadores/análise , Cocaína/análogos & derivados , Cocaína/análise , Feminino , Humanos , Masculino , Mastigação , Pessoa de Meia-Idade , Folhas de Planta , Pirrolidinas/análise , Fumar , Chá , Adulto Jovem
6.
ACS Sens ; 4(2): 456-463, 2019 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-30644723

RESUMO

Bioreactors have been used both to develop new, and to improve bioprocess yields for, biopharmaceutical products. However, efforts to miniaturize bioreactors, in order to save costs and accelerate process development times, have been limited by the lack of on-site monitoring capabilities available at such scales. In this study, small volume (3 nL) nonconsumptive holographic sensors were integrated into a glass-PDMS microfluidic chip to monitor via a blue-shift in the resultant holographic replay wavelength, the change in pH during microbial growth of Lactobacillus casei ( L. casei) Shirota. Within the optimal growth pH range of L. casei, the accuracy of the miniaturized pH sensors was comparable to that of a conventional pH meter. Conceivably, this approach could be extrapolated to an array of miniaturized holographic sensors sensitive to different analytes, and thereby paving the way for reliable, real-time, noninvasive monitoring of microorganisms in a nanobioreactor.


Assuntos
Holografia/instrumentação , Dispositivos Lab-On-A-Chip , Lactobacillus casei/crescimento & desenvolvimento , Acetona/análogos & derivados , Acetona/química , Dimetilpolisiloxanos/química , Concentração de Íons de Hidrogênio , Metacrilatos/química , Nylons/química
7.
F1000Res ; 8: 1220, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32148759

RESUMO

Background: To obtain accurate measurements of cortisol (C) and testosterone (T) in Aceh cattle, commercial enzyme-linked immunosorbent assay (ELISA) kits need to be carefully validated. Moreover, repeated freeze-thaw cycles during the storage of the samples may affect the stability of the hormones in the serum. Here, we test the reliability of C and T concentration measurements in the serum of Aceh cattle, obtained using commercial C and T ELISA kits designed to measure human C and T concentrations. Further, we evaluate the effect of repeated freeze-thaw cycles on the stability of C and T concentrations in the serum. Methods: Commercial C (Cat. no. EIA-1887) and T (Cat. no. EIA-1559) ELISA kits from DRG Instruments GmbH were validated through an analytical validation test (i.e., parallelism, accuracy, and precision) and a biological validation test (for C: effect of transportation on the C excretion; for T: the concentrations of T between bulls and cows). To test the effects of freeze-thaw cycles, cattle serum was subjected to the following treatments: (i) remained frozen at -20 OC (control group); (ii) exposed to freeze-thaw cycles for two, four, six, and eight times (test groups).   Results: Parallelism, accuracy, and precision tests showed that both  C and T ELISA kits adequately measured C and T in the serum of Aceh cattle. Concentrations of C post-transportation were significantly higher than pre-transportation (p<0.05). Concentrations of T in bulls were significantly higher than in cows (p<0.05). After four to eight freeze-thaw cycles, C concentrations were significantly lower compared to the control group (all p < 0.05). In contrast, T concentrations remained stable (all p>0.05). Conclusions: Commercial C (EIA-1887) and T (EIA-1559) ELISA kits are reliable assays for measuring serum C and T, respectively, in Aceh cattle. Repeated freeze-thaw cycles significantly affected the stability of serum C, but did not for T.


Assuntos
Ensaio de Imunoadsorção Enzimática , Hidrocortisona , Testosterona , Acetona/análogos & derivados , Animais , Bovinos , Feminino , Hidrazonas , Hidrocortisona/análise , Masculino , Reprodutibilidade dos Testes , Testosterona/análise
8.
J Biol Chem ; 293(51): 19909-19918, 2018 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-30361441

RESUMO

Bacterial microcompartments encapsulate enzymatic pathways that generate small, volatile, aldehyde intermediates. The Rhodococcus and Mycobacterium microcompartment (RMM) operon from Mycobacterium smegmatis encodes four enzymes, including (S)-1-amino-2-propanol dehydrogenase and a likely propionaldehyde dehydrogenase. We show here that a third enzyme (and its nonmicrocompartment-associated paralog) is a moderately specific (S)-1-amino-2-propanol kinase. We determined the structure of apo-aminopropanol kinase at 1.35 Å, revealing that it has structural similarity to hexosamine kinases, choline kinases, and aminoglycoside phosphotransferases. We modeled substrate binding, and tested our model by characterizing key enzyme variants. Bioinformatics analysis established that this enzyme is widespread in Actinobacteria, Proteobacteria, and Firmicutes, and is very commonly associated with a candidate phospholyase. In Rhizobia, aminopropanol kinase is generally associated with aromatic degradation pathways. In the RMM (and the parallel pathway that includes the second paralog), aminopropanol kinase likely degrades aminoacetone through a propanolamine-phosphate phospho-lyase-dependent pathway. These enzymatic activities were originally described in Pseudomonas, but the proteins responsible have not been previously identified. Bacterial microcompartments typically co-encapsulate enzymes which can regenerate required co-factors, but the RMM enzymes require four biochemically distinct co-factors with no overlap. This suggests that either the RMM shell can uniquely transport multiple co-factors in stoichiometric quantities, or that all enzymes except the phospho-lyase reside outside of the shell. In summary, aminopropanol kinase is a novel enzyme found in diverse bacteria and multiple metabolic pathways; its presence in the RMM implies that this microcompartment degrades aminoacetone, using a pathway that appears to violate some established precepts as to how microcompartments function.


Assuntos
Acetona/análogos & derivados , Mycobacterium smegmatis/enzimologia , Acetona/química , Acetona/metabolismo , Sequência de Aminoácidos , Domínio Catalítico , Cinética , Modelos Moleculares
9.
Biochemistry ; 57(26): 3780-3789, 2018 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-29757625

RESUMO

S-(+)-1-Amino-2-propanol dehydrogenase (APDH) is a short-chain dehydrogenase/reductase associated with the incompletely characterized Rhodococcus and Mycobacterium bacterial microcompartment (RMM). We enzymatically characterized the APDH from M. smegmatis and showed it is highly selective, with a low micromolar Km for S-(+)-1-amino-2-propanol and specificity for NADP(H). A paralogous enzyme from a nonmicrocompartment-associated operon in the same organism was also shown to have a similar activity. We determined the structure of APDH in both apo form (at 1.7 Å) and as a ternary enzyme complex with NADP+ and aminoacetone (at 1.9 Å). Recognition of aminoacetone was mediated by strong hydrogen bonds to the amino group by Thr145 and by Glu251 from the C-terminus of an adjacent protomer. The substrate binding site entirely encloses the substrate, with close contacts between the aminoacetone methyl group and Phe95, Trp154, and Leu195. Kinetic characterization of several of these residues confirm their importance in enzyme functioning. Bioinformatics analysis of APDH homologues implies that many nonmicrocompartment APDH orthologues partake in an aminoacetone degradation pathway that proceeds via an aminopropanol O-phosphate phospholyase. RMM microcompartments may mediate a similar pathway, though possibly with differences in the details of the pathway that necessitates encapsulation behind a shell.


Assuntos
Oxirredutases do Álcool/ultraestrutura , Proteínas de Bactérias/ultraestrutura , Mycobacterium smegmatis/enzimologia , Acetona/análogos & derivados , Acetona/metabolismo , Oxirredutases do Álcool/química , Proteínas de Bactérias/química , Cristalografia por Raios X , Humanos , Cinética , Modelos Moleculares , NADP/metabolismo , Propanolaminas/metabolismo , Conformação Proteica , Especificidade por Substrato
10.
Appl Microbiol Biotechnol ; 102(11): 4717-4727, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29627855

RESUMO

Acyloin condensation between benzaldehyde and decarboxylated pyruvate results in the production of R-(-)-phenylacetylcarbinol, a chiral precursor of the drug ephedrine. Huge research efforts have been made to improve the conditions of this reaction and to avoid the generation of by-products. Recently, we reported the advantages of using whole cells of the yeast Debaryomyces etchellsii as biocatalysts for this purpose. In this work, a new strategy, which fulfills green chemistry principles, is proposed and is based on using seawater as a gentle solvent. We demonstrate that, under these conditions, several improvements can be made compared to employing freshwater: (1) the conversion of the starting material in (R)-PAC is higher and with a minimum production of by-products; (2) it is possible to increase at least twofold the benzaldehyde load in the reaction medium; (3) cells can maintain their activity after several recycling rounds, which makes (R)-PAC production an easy and economical process.


Assuntos
Acetona/análogos & derivados , Ascomicetos/metabolismo , Pró-Fármacos/metabolismo , Tecnologia Farmacêutica/métodos , Acetona/química , Acetona/metabolismo , Biotransformação , Pró-Fármacos/química , Água do Mar/química
11.
J Environ Sci (China) ; 66: 1-11, 2018 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-29628075

RESUMO

Methacrolein (MACR) is an abundant multifunctional carbonyl compound with high reactivity in the atmosphere. In this study, we investigated the hydroxyl radical initiated oxidation of MACR at various NO/MACR ratios (0 to 4.04) and relative humidities (<3% to 80%) using a flow tube. Meanwhile, a box model based on the Master Chemical Mechanism was performed to test our current understanding of the mechanism. In contrast to the reasonable predictions for hydroxyacetone production, the modeled yields of formaldehyde (HCHO) were twice higher than the experimental results. The discrepancy was ascribed to the existence of unconsidered non-HCHO forming channels in the chemistry of CH3C(CH2)OO, which account for approx. 50%. In addition, the production of hydroxyacetone and HCHO were affected by water vapor as well as the initial NO/MACR ratio. The yields of HCHO were higher under humid conditions than that under dry condition. The yields of hydroxyacetone were higher under humid conditions at low-NOx level, while lower at high-NOx level. The reasonable explanation for the lower hydroxyacetone yield under humid conditions at high-NOx level is that water vapor promotes the production of methacrolein nitrate in the reaction of HOCH2C(CH3)(OO)CHO with NO due to the peroxy radical-water complex formation, which was evidenced by calculational results. And the minimum equilibrium constant of this water complex formation was estimated to be 1.89×10-18cm3/molecule. These results provide new insights into the MACR oxidation mechanism and the effects of water vapor.


Assuntos
Acetona/análogos & derivados , Acroleína/análogos & derivados , Poluentes Atmosféricos/química , Formaldeído/química , Modelos Químicos , Acetona/química , Acroleína/química , Atmosfera/química , Radical Hidroxila/química , Óxidos de Nitrogênio/química , Processos Fotoquímicos
12.
Phys Chem Chem Phys ; 20(4): 2558-2570, 2018 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-29318252

RESUMO

Phenylacetone monooxygenase is the most stable and thermo-tolerant member of the Baeyer-Villiger monooxygenases family, and therefore it is an ideal candidate for the synthesis of industrially relevant ester or lactone compounds. However, its limited substrate scope has largely limited its industrial applications. Linear substrates are interesting from an industrial point of view, it is thus necessary to identify the essential spatial requirement for achieving high conversions for non-native linear substrates. Here using molecular dynamics simulations, we compared the conversion of a non-native linear substrate 2-octanone and the native substrate phenylacetone, catalyzed by the WT enzyme and a quadruple variant P253F/G254A/R258M/L443F that exhibits significantly improved activity towards 2-octanone. We uncovered that a remarkable movement of L289 is crucial for a reshaping of the active site of the quadruple variant so as to prevent the aliphatic substrate from moving away from the C4a-peroxyflavin, thus enabling it to keep a catalytically relevant pose during the oxygenation process. By performing steady-state kinetic analysis of two single-mutation variants at position 258, we further validated that the L289 reposition is attributed to the combined effect of quadruple mutations. In order to further explore the substrate scope of PAMO we also studied the binding of cyclopentanone and 2-phenylcyclohexanone, which are the typical substrates of CPMO in group I and CHMO in group III, respectively. Our study provides fundamental atomic-level insights in rational engineering of PAMO for wide applications in industrial biocatalysis, in particular, in the biotransformation of long-chain aliphatic oils into potential biodiesels.


Assuntos
Oxigenases de Função Mista/metabolismo , Acetona/análogos & derivados , Acetona/química , Acetona/metabolismo , Actinobacteria/enzimologia , Sequência de Aminoácidos , Sítios de Ligação , Biocatálise , Domínio Catalítico , Cetonas/química , Cetonas/metabolismo , Cinética , Oxigenases de Função Mista/química , Oxigenases de Função Mista/genética , Simulação de Dinâmica Molecular , Mutagênese Sítio-Dirigida , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Alinhamento de Sequência , Especificidade por Substrato
13.
J Integr Plant Biol ; 60(3): 190-194, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29058786

RESUMO

Flowers are required for the Darwinian fitness of flowering plants, but flowers' advertisements for pollination services can attract florivores. Previous glasshouse work with Nicotiana attenuata revealed the role of jasmonate (JA) signaling in flower development, advertisement and defense. However, whether JA signaling mediates flowers' filtering of floral visitors in nature remained unknown. This field study revealed that silencing JA signaling resulted in flowers that produce less nectar and benzyl acetone, two pollinator-attractive traits. Meanwhile, flowers of defenseless plants were highly attacked by a suite of native herbivores, and damage to buds in native plants correlated negatively with their JA-Ile levels.


Assuntos
Ciclopentanos/metabolismo , Flores/metabolismo , Herbivoria/fisiologia , Insetos/fisiologia , Oxilipinas/metabolismo , Polinização/fisiologia , Transdução de Sinais , Acetona/análogos & derivados , Acetona/metabolismo , Animais , Inativação Gênica , Néctar de Plantas , Tabaco/imunologia , Tabaco/metabolismo
14.
J Steroid Biochem Mol Biol ; 177: 250-254, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28716761

RESUMO

Among numerous studies on synthetic approaches to and the biological activities of vitamin D analogues, we herein focused on falecalcitriol, an analogue of calcitriol (1α,25-dihydroxyvitamin D3), in which a 26,26,26,27,27,27-hexafluoroisopropanol unit has been introduced into the side chain. Falecalcitriol was designed to escape from the metabolism of CYP24A1 and has been used as a drug to treat secondary hyperparathyroidism since 2001. Its metabolite, the 23-hydroxy form, retains biological activity and resistants to further metabolism. Recent developments in synthetic methodologies for introducing the hexafluoroisopropanol unit into the vitamin D CD-ring side chain were described herein.


Assuntos
Calcitriol/análogos & derivados , Propanóis/química , Acetona/análogos & derivados , Acetona/química , Calcitriol/química , Fluorcarbonetos/química
15.
ChemSusChem ; 10(15): 3105-3110, 2017 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-28643864

RESUMO

Here, we propose the use of hydroxyacetone, a dehydration product of glycerol, as a platform for the electrocatalytic synthesis of acetone, 1,2-propanediol, and 2-propanol. 11 non-noble metals were investigated as electrode materials in combination with three different electrolyte compositions toward the selectivity, Coulombic efficiency (CE), and reaction rates of the electrocatalytic hydrogenation (formation of 1,2-propanediol) and hydrodeoxygenation (formation of acetone and propanol) of hydroxyacetone. With a selectivity of 84.5 %, a reaction rate of 782 mmol h-1 m-2 and a CE of 32 % (for 0.09 m hydroxyacetone), iron electrodes, in a chloride electrolyte, yielded the best 1,2 propanediol formation. A further enhancement of the performance can be achieved upon increasing the educt concentration to 0.5 m, yielding a reaction rate of 2248.1 mmol h-1 m-2 and a CE of 64.5 %. Acetone formation was optimal at copper and lead electrodes in chloride solution, with lead showing the lowest tendency of side product formation. 2-propanol formation can be achieved using a consecutive oxidation of the formed acetone (at iron electrodes). 1-propanol formation was observed only in traces.


Assuntos
Acetona/análogos & derivados , Glicerol/química , Oxigênio/química , Acetona/química , Catálise , Eletroquímica , Eletrodos , Hidrogenação , Oxirredução
16.
Drug Test Anal ; 9(7): 966-976, 2017 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-28332334

RESUMO

This perspective examines amphetamine importations into Ireland. Some novel by-products were detected and linked to a change in the method of production of P2P from APAAN. These by-products remained present during subsequent Leuckart reaction conditions. Novel by-products from substituted cathinone synthesis reactions were also isolated and characterized.


Assuntos
Acetona/análogos & derivados , Acetonitrilos/química , Anfetamina/química , Estimulantes do Sistema Nervoso Central/química , Contaminação de Medicamentos , Drogas Ilícitas/química , Acetona/síntese química , Acetona/química , Acetonitrilos/síntese química , Anfetamina/síntese química , Estimulantes do Sistema Nervoso Central/síntese química , Cromatografia Gasosa-Espectrometria de Massas , Hidrólise , Drogas Ilícitas/síntese química , Irlanda , Farmácia
17.
Huan Jing Ke Xue ; 38(3): 1038-1045, 2017 Mar 08.
Artigo em Chinês | MEDLINE | ID: mdl-29965574

RESUMO

Formation characteristics and transferring feature of nitrogenous/carbonaceous disinfection by-products have been observed under different ozone dosages and pH conditions, and essential nature conversion of Algae organic matters has been also studied concurrently, based on high algae-laden water. The results showed as follows:reduction of Microcystis aeruginosa could reach 36% at the ozonation concentration of 28.92 mg·L-1. Humic acid-like compounds first increased and then decreased with continuing addition of ozone dosage, whereas soluble microbial products, fulvic acids and aromatic protein substance all diminished. Low dosage of ozone had certain effect on control of dichloroacetonitrile(DCAN) and trichloroacetonitrile (TCAN) formation potential, yet augmented the yield of trichloronitromethane (TCNM) and 1,1,1-trichloroacetone(1,1,1-TCP) precursors, and N-DBPs formation potential was promoted with the increase of ozone dosage. Algae removal efficiency was relatively the best under the acidic condition, meanwhile, UV254 and DOC increased with the rise of pH, though the change was not outstanding. Humic acid-like compounds decreased with the rise of pH; ozonation could degrade the soluble microbial products and the consequence was affected little by the change of pH. DCAN and TCAN formation potential decreased with the rise of pH; TCNM formation potential appeared to be the highest when the pH was 10, whereas the highest 1,1,1-TCP formation potential was found at pH 7.


Assuntos
Desinfecção , Microcystis , Ozônio/química , Poluentes Químicos da Água/análise , Purificação da Água , Acetona/análogos & derivados , Acetona/análise , Acetonitrilos/análise , Hidrocarbonetos Clorados/análise , Concentração de Íons de Hidrogênio , Água
18.
Drug Test Anal ; 9(3): 446-452, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26768537

RESUMO

1-Phenyl-2-propanone (P2P) is an internationally monitored precursor that has become increasingly difficult for illicit amphetamine producers to source, which means that alternative routes to its preparation have become increasingly important. One such approach includes the hydrolysis of alpha-phenylacetoacetonitrile (APAAN) with sulfuric acid. Previously, we reported the identification of 4,6-dimethyl-3,5-diphenylpryid-2-one following implementation of hydrolysis conditions and it was proposed that this compound might serve as one route specific by-product in the APAAN to P2P conversion. This study continued to explore the presence of impurities formed during this conversion and expanded also into a second route of P2P synthesis starting from alpha-methylstyrene (AMS). All P2P products underwent the Leuckart procedure to probe the presence of P2P-related impurities that might have carried through to the final product. Two by-products associated with the APAAN hydrolysis route to P2P were identified as 2,3-diacetyl-2,3-diphenylsuccinonitrile (1) and 2-methyl-1-phenyl-1,3-dicarbonitrile-1H-indene (2), respectively. Two by-products associated with the AMS route to P2P and subsequent Leuckart reaction were 1,1,3-trimethyl-3-phenyl-2,3-dihydro-1H-indene (3) and 1-phenyl-N-(phenylethyl)propan-2-amine (4), respectively. The two indenes (2 and 3) identified in synthesized amphetamine originating from P2P suggested that it might be possible to differentiate between the two synthetic routes regarding the use of APAAN and AMS. Furthermore, the association of these compounds with amphetamine production appears to have been reported for the first time. The presence of compounds 1 - 4 in seized amphetamine samples and waste products could facilitate the suggestion whether APAAN or AMS were employed in the synthesis route to the P2P. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Acetona/análogos & derivados , Anfetamina/síntese química , Estimulantes do Sistema Nervoso Central/síntese química , Contaminação de Medicamentos , Indenos/análise , Acetona/síntese química , Acetona/química , Anfetamina/química , Estimulantes do Sistema Nervoso Central/química , Cromatografia Líquida , Cristalografia por Raios X , Cromatografia Gasosa-Espectrometria de Massas , Drogas Ilícitas/síntese química , Drogas Ilícitas/química , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Estirenos/síntese química , Estirenos/química
19.
Drug Test Anal ; 9(2): 323-326, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27004438

RESUMO

Hygrine (HYG) and cuscohygrine (CUS) are natural alkaloids of coca leaves but are not found in illicit cocaine seizures. Therefore, they were proposed as markers for coca chewing in contrast to cocaine abuse in urine and hair testing. In order to examine at which step of the illegal cocaine production these compounds are lost, coca leaves were processed according to an authentic procedure by extraction with lime and kerosene, re-extraction with sulphuric acid, and precipitation of coca paste with ammonia. Non-extracted and extracted coca leaves, acidic extract and coca paste were analyzed by gas chromatography-mass spectrometry (GC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) for cocaine, ecgonine methyl ester (EME), cinnamoylcocaine (CIN), HYG, and CUS. It follows from the results that under these conditions, HYG and CUS are extracted only to a minor extent by kerosene and are not precipitated from the acidic re-extract in the coca paste. Due to this behaviour in illegal cocaine production, they fulfil the conditions as markers for coca chewing in an optimal way. However, for unambiguous discrimination between coca chewing and cocaine abuse in human samples, additional markers of manufactured cocaine are required. Copyright © 2016 John Wiley & Sons, Ltd.


Assuntos
Acetona/análogos & derivados , Coca/química , Cocaína/análise , Folhas de Planta/química , Pirrolidinas/análise , Acetona/análise , Cromatografia Líquida , Cocaína/análogos & derivados , Transtornos Relacionados ao Uso de Cocaína/diagnóstico , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Drogas Ilícitas/análise , Mastigação
20.
Drug Test Anal ; 9(3): 453-461, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26033896

RESUMO

A trace processing impurity found in certain methamphetamine exhibits was isolated and identified as trans-N-methyl-4-methyl-5-phenyl-4-penten-2-amine hydrochloride (1). It was determined that this impurity was produced via reductive amination of trans-4-methyl-5-phenyl-4-penten-2-one (4), which was one of a cluster of related ketones generated during the synthesis of 1-phenyl-2-propanone (P2P) from phenylacetic acid and lead (II) acetate. This two-step sequence resulted in methamphetamine containing elevated levels of 1. In contrast, methamphetamine produced from P2P made by other methods produced insignificant (ultra-trace or undetectable) amounts of 1. These results confirm that 1 is a synthetic marker compound for the phenylacetic acid and lead (II) acetate method. Analytical data for 1 and 4, and a postulated mechanism for the production of 4, are presented. Copyright © 2015 John Wiley & Sons, Ltd.


Assuntos
Acetona/análogos & derivados , Estimulantes do Sistema Nervoso Central/síntese química , Contaminação de Medicamentos , Drogas Ilícitas/síntese química , Metanfetamina/síntese química , Compostos Organometálicos/química , Fenilacetatos/química , Acetona/síntese química , Acetona/química , Aminação , Estimulantes do Sistema Nervoso Central/química , Drogas Ilícitas/química , Metanfetamina/química , Compostos Organometálicos/síntese química , Oxirredução , Fenilacetatos/síntese química
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