Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 3 de 3
Filtrar
Mais filtros

Base de dados
Tipo de documento
País de afiliação
Intervalo de ano de publicação
1.
Sci Justice ; 58(5): 355-365, 2018 09.
Artigo em Inglês | MEDLINE | ID: mdl-30193661

RESUMO

Marijuana, a drug derived from the Cannabis sativa L. plant, is the world's most consumed illicit drug. In this paper, a total of 156 marijuana samples seized in the state of Espírito Santo (ES), Brazil were studied and analysed by proton nuclear magnetic resonance (1H NMR) spectroscopy to identify the major cannabinoids present. A crude extract of all samples was purified using high performance liquid chromatography so that these compounds could serve as reference substances. Nine fractions were obtained and analysed by 1H NMR and gas chromatography-mass spectrometry (GC-MS), with five presented cannabinoids. ∆9-THC (Δ9-trans-tetrahydrocannabinol), ∆9-THCA (∆9-tetrahydrocannabinolic acid), ∆8-THC (∆8-tetrahydrocannabinol), 11-hydroxycannabinol, CBV (cannabivarin), and CBN (cannabinol) were found, and their chemical structures were confirmed by GC-MS. The latter compound was obtained with high purity (≈100%), while the others were obtained as less complex mixtures with purity higher than 75% (except for Δ8-THC). Principal component analysis (PCA) was used on the 1H NMR spectra of the 156 samples, and it was found that the samples were grouped according to the months, differentiating into two groups (from July 2014 to January 2015 and from February 2015 to July 2015), where non-grouping was observed from four macro-regions of the ES state (North, Central, Metropolitan, and South). The chemical profile of the seized samples was correlated to the 1H NMR spectrum of an isolated CBN sub-fraction, in which the group formed by samples seized in the year 2015 presented lower CBN content in the chemical composition. From the PCA score plot, two groups of samples were confirmed using the partial least squares discriminant analysis and orthogonal projections to latent structures classification methods.


Assuntos
Canabinoides/análise , Cannabis/química , Espectroscopia de Prótons por Ressonância Magnética , Canabinoides/química , Cromatografia Líquida de Alta Pressão , Tráfico de Drogas , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Estrutura Molecular
2.
J Phys Chem A ; 113(42): 11161-6, 2009 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-19534497

RESUMO

Titan, the largest satellite of Saturn, has an atmosphere chiefly made up of N(2) and CH(4) and includes traces of many simple organic compounds. This atmosphere also partly consists of haze and aerosol particles which during the last 4.5 gigayears have been processed by electric discharges, ions, and ionizing photons, being slowly deposited over the Titan surface. In this work, we investigate the possible effects produced by soft X-rays (and secondary electrons) on Titan aerosol analogs in an attempt to simulate some prebiotic photochemistry. The experiments have been performed inside a high vacuum chamber coupled to the soft X-ray spectroscopy beamline at the Brazilian Synchrotron Light Source, Campinas, Brazil. In-situ sample analyses were performed by a Fourier transform infrared spectrometer. The infrared spectra have presented several organic molecules, including nitriles and aromatic CN compounds. After the irradiation, the brownish-orange organic residue (tholin) was analyzed ex-situ by gas chromatographic (GC/MS) and nuclear magnetic resonance ((1)H NMR) techniques, revealing the presence of adenine (C(5)H(5)N(5)), one of the constituents of the DNA molecule. This confirms previous results which showed that the organic chemistry on the Titan surface can be very complex and extremely rich in prebiotic compounds. Molecules like these on the early Earth have found a place to allow life (as we know) to flourish.


Assuntos
Adenina/síntese química , Adenina/efeitos da radiação , Meio Ambiente Extraterreno/química , Saturno , Adenina/química , Atmosfera/química , Dióxido de Carbono/síntese química , Dióxido de Carbono/química , Monóxido de Carbono/síntese química , Monóxido de Carbono/química , Cianatos/síntese química , Cianatos/química , Cromatografia Gasosa-Espectrometria de Massas , Hidrocarbonetos Aromáticos/síntese química , Hidrocarbonetos Aromáticos/química , Espectroscopia de Ressonância Magnética , Metano/síntese química , Metano/química , Nitrilas/síntese química , Nitrilas/química , Nitrogênio/química , Espectroscopia de Infravermelho com Transformada de Fourier , Água/química , Raios X
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA