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1.
Neurosci Lett ; 629: 68-72, 2016 08 26.
Artigo em Inglês | MEDLINE | ID: mdl-27369324

RESUMO

The abuse of alkyl nitrites is common among adolescents and young adults worldwide. However, the information regarding the effects of alkyl nitrites on the central nervous system and the associated psychological abuse potential is scarce. The abuse potential of 3 representative alkyl nitrites - isobutyl nitrite, isoamyl nitrite, and butyl nitrite - was evaluated in mice using conditioned place preference tests with an unbiased method. The dopamine levels released by synaptosomes extracted from the striatal region were measured using high performance liquid chromatography. Mice treated with the test substances (50mg/kg, i.p.) exhibited a significantly increased drug-paired place preference. Moreover, greater levels of dopamine were released by striatal region synaptosomes in response to isobutyl nitrite treatment in mice. Thus, our findings suggest that alkyl nitrites could lead to psychological dependence and dopaminergic effects. Furthermore, these results provide scientific evidence to support the regulation of alkyl nitrites as psychoactive substances in the future.


Assuntos
Nitrito de Amila/análogos & derivados , Condicionamento Clássico/efeitos dos fármacos , Corpo Estriado/efeitos dos fármacos , Dopamina/metabolismo , Nitritos/toxicidade , Transtornos Relacionados ao Uso de Substâncias/etiologia , Nitrito de Amila/química , Nitrito de Amila/toxicidade , Animais , Corpo Estriado/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos ICR , Nitritos/química , Receptores de N-Metil-D-Aspartato/metabolismo , Sinaptossomos/efeitos dos fármacos , Sinaptossomos/metabolismo
2.
J Phys Chem A ; 116(24): 6327-40, 2012 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-22530669

RESUMO

The primary products of n-butoxy and 2-pentoxy isomerization in the presence and absence of O(2) have been detected using pulsed laser photolysis-cavity ringdown spectroscopy (PLP-CRDS). Alkoxy radicals n-butoxy and 2-pentoxy were generated by photolysis of alkyl nitrite precursors (n-butyl nitrite or 2-pentyl nitrite, respectively), and the isomerization products with and without O(2) were detected by infrared cavity ringdown spectroscopy 20 µs after the photolysis. We report the mid-IR OH stretch (ν(1)) absorption spectra for δ-HO-1-C(4)H(8)•, δ-HO-1-C(4)H(8)OO•, δ-HO-1-C(5)H(10)•, and δ-HO-1-C(5)H(10)OO•. The observed ν(1) bands are similar in position and shape to the related alcohols (n-butanol and 2-pentanol), although the HOROO• absorption is slightly stronger than the HOR• absorption. We determined the rate of isomerization relative to reaction with O(2) for the n-butoxy and 2-pentoxy radicals by measuring the relative ν(1) absorbance of HOROO• as a function of [O(2)]. At 295 K and 670 Torr of N(2) or N(2)/O(2), we found rate constant ratios of k(isom)/k(O(2)) = 1.7 (±0.1) × 10(19) cm(-3) for n-butoxy and k(isom)/k(O(2)) = 3.4(±0.4) × 10(19) cm(-3) for 2-pentoxy (2σ uncertainty). Using currently known rate constants k(O(2)), we estimate isomerization rates of k(isom) = 2.4 (±1.2) × 10(5) s(-1) and k(isom) ≈ 3 × 10(5) s(-1) for n-butoxy and 2-pentoxy radicals, respectively, where the uncertainties are primarily due to uncertainties in k(O(2)). Because isomerization is predicted to be in the high pressure limit at 670 Torr, these relative rates are expected to be the same at atmospheric pressure. Our results include corrections for prompt isomerization of hot nascent alkoxy radicals as well as reaction with background NO and unimolecular alkoxy decomposition. We estimate prompt isomerization yields under our conditions of 4 ± 2% and 5 ± 2% for n-butoxy and 2-pentoxy formed from photolysis of the alkyl nitrites at 351 nm. Our measured relative rate values are in good agreement with and more precise than previous end-product analysis studies conducted on the n-butoxy and 2-pentoxy systems. We show that reactions typically neglected in the analysis of alkoxy relative kinetics (decomposition, recombination with NO, and prompt isomerization) may need to be included to obtain accurate values of k(isom)/k(O(2)).


Assuntos
Nitrito de Amila/química , Nitritos/química , Oxigênio/química , Cinética , Lasers , Fotólise , Análise Espectral , Estereoisomerismo
3.
J Phys Chem A ; 116(2): 810-9, 2012 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-22175717

RESUMO

We have investigated the deep-UV photoinduced, homolytic bond cleavage of amyl nitrite to form NO and pentoxy radicals. One-color multiphoton ionization with ultrashort laser pulses through the S(2) state resonance gives rise to photoelectron spectra that reflect ionization from the S(1) state. Time-resolved pump-probe photoionization measurements show that upon excitation at 207 nm, the generation of NO in the v = 2 state is delayed, with a rise time of 283 (16) fs. The time-resolved mass spectrum shows the NO to be expelled with a kinetic energy of 1.0 eV, which is consistent with dissociation on the S(1) state potential energy surface. Combined, these observations show that the first step of the dissociation reaction involves an internal conversion from the S(2) to the S(1) state, which is followed by the ejection of the NO radical on the predissociative S(1) state potential energy surface.


Assuntos
Nitrito de Amila/química , Fotólise , Raios Ultravioleta , Radicais Livres/química , Cinética , Espectrometria de Massas , Óxido Nítrico/química , Pentoxil (Uracila)/química , Espectroscopia Fotoeletrônica , Teoria Quântica , Propriedades de Superfície
5.
Ultrason Sonochem ; 15(4): 279-282, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17959410

RESUMO

The reaction of 6-acylmethylphenanthridines with isoamyl nitrite results alpha-oximino-6-acylmethylphenanthridines in 73-95% yields in DMF under ultrasound irradiation. Compared with conventional methods, the main advantages of the present procedure are milder conditions, shorter reaction time and higher yields.


Assuntos
Oximas/síntese química , Fenantridinas/síntese química , Nitrito de Amila/análogos & derivados , Nitrito de Amila/química , Nitrito de Amila/efeitos da radiação , Indicadores e Reagentes , Espectroscopia de Ressonância Magnética , Nitrosação/efeitos da radiação , Fenantridinas/química , Fenantridinas/efeitos da radiação , Espectrofotometria Infravermelho , Sulfatos/química , Ultrassom
6.
Anal Biochem ; 354(2): 165-8, 2006 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-16750156

RESUMO

A method for the synthesis of peroxynitrite is described. It involves nitrosation of H2O2 at pH> or = 12.5 by isoamyl or butyl nitrite in mixed solvents of isopropyl alcohol (IPA) and water at 25+/-1 degrees C. Maximum yields of peroxynitrite are obtained after 15 min of incubation at IPA concentrations of 30-70% (v/v). The solutions of peroxynitrite are processed for removal of IPA and isoamyl alcohol by solvent extraction. Unreacted H2O2 is removed by catalytic decomposition on granular MnO(2). The post processed solutions of peroxynitrite are useful in several chemical and biochemical investigations where bolus additions are required. The method as reported is amenable for large scale synthesis as it involves sequential mixing of solvents (water and IPA) to alkali followed by the addition of H2O2 and alkyl nitrite.


Assuntos
Ácido Peroxinitroso/síntese química , 2-Propanol , Nitrito de Amila/análogos & derivados , Nitrito de Amila/química , Peróxido de Hidrogênio/química , Indicadores e Reagentes , Ácido Peroxinitroso/química , Solventes , Espectrofotometria
7.
Anal Biochem ; 236(2): 242-9, 1996 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-8723544

RESUMO

A new method for the preparation of high concentrations of peroxynitrite (up to 1 M) is described. The synthesis uses a two-phase system and involves a displacement reaction by the hydroperoxide anion (in the aqueous phase) on isoamyl nitrite (in the organic phase). The product peroxynitrite remains in the aqueous phase, whereas isoamyl alcohol forms a new organic phase along with the unreacted isoamyl nitrite. The aqueous phase contains some 0.15 M isoamyl alcohol and the unreacted hydrogen peroxide, but no isoamyl nitrite. Removal of isoamyl alcohol or traces of isoamyl nitrite is accomplished by washing the aqueous phase with dichloromethane, chloroform, or hexane. A near total removal of hydrogen peroxide is then achieved by passing the solutions through a short column of manganese dioxide. The peroxynitrite in these postprocessed solutions has broad absorption spectrum with a maximum around 302 nm, follows a characteristic first-order decomposition at pH 7.2 and 25 degrees C (k = 0.34 +/- 0.1 s-1), and reacts with organic compounds to give either nitrated or one-electron transfer products. When stored frozen at -20 degrees C, these peroxynitrite solutions decompose at a rate of about 1.7 % per day and should be used within 2-4 weeks. For short-term storage of about 1 week or less, these solutions can be stored at refrigerator temperatures (approximately 5 degrees C) where peroxynitrite has a half-life of about 7 days.


Assuntos
Nitrito de Amila/análogos & derivados , Peróxido de Hidrogênio/química , Nitratos/síntese química , Nitrito de Amila/química , Fenômenos Químicos , Físico-Química , Cinética , Nitratos/análise , Oxirredução , Estereoisomerismo
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