21 research outputs found
Análisis de composición de un comprimido azul de nombre desconocido
Get PDFLa contribución describe cómo realizar el análisis de composición parcial de un comprimido de color azul de nombre desconocido pero que podría contener fentanilo. El procedimiento de análisis incluye la lixiviación y purificación de los componentes mayoritarios, la obtención de los espectros de ultravioleta y de infrarrojo de los componentes puros, y la correlación espectro-estructura. Con base en los resultados, se discuten las limitaciones del procedimiento experimental para detectar e identificar a los componentes de muy baja concentración en la muestra inicial.Partial quantitative composition of a blue tablet without commercial name was determined by using conventional separation and purification methods. Isolated organic compounds were analysed by ultraviolet and infrared spectroscopy, and the resulting spectra were correlated with the corresponding molecular structure. The blue color of the tablets suggests they could contain fentanyl; however, the experimental procedure was unsuitable to detect the very small amount of such substance, if present
Síntesis racémica de 1-(10-nitro-9-antril)etanol
Get PDFCon el fin de evaluar el incremento en la acidez relativa del hidrógeno bencílico causada por el grupo nitro en los agentes quirales de solvatación análogos de ariletanol, se realizó la síntesis racémica de 1-(10-nitro-9-antril) etanol en dos pasos. En el primero se efectuó la nitración de 9-acetilantraceno con nitrato de acetilo y se obtuvo 28% de 10-nitro-9-acetilantraceno. En el segundo paso se redujo el grupo carbonilo presente en 10-nitro-9-acetilantraceno con hidruro de boro sodio para obtener 1-(10-nitro-9-antril) etanol. El incremento de la acidez del hidrógeno bencílico, se estimó al comparar los desplazamientos químicos de la señal de dicho hidrógeno bencílico observado en los espectros de RMN de protón de 1-(10-nitro-9-antril) etanol y 9-antriletanol racémicos.In order to evaluate the enhancement in relative acidity of benzylic hydrogen caused by nitro group in arylethanol analogous, the two-step racemic synthesis of 1-(10-nitro-9- anthryl) ethanol was carried out. Commercially available 9-acetylanthacene was treated with acetyl nitrate to give 10-nitro-9- acetylanthracene in 28% yield. This compound was then reduced with sodium borohydride in methanol- THF solution to afford 1-(10-nitro-9-anthryl) ethanol in 32% yield. Acidity enhancement of benzylic hydrogen was estimated by comparison of its chemical shift observed in proton NMR spectra of 1-(10- nitro-9-anthyl) ethanol and 9-anthryletanol, they both in racemic form
Detective fiction in Cuban society and culture.
No full textPhDThe object of this thesis is to reach towards an understanding of Cuban society through a
study of its detective fiction and more particularly contemporary Cuban society through
the novels of the author and critic, Leonardo Padura Fuentes.
The method has been to trace the development of Cuban detective writing and to
read Padura Fuentes in the light of the work of twentieth century Western European
literary critics and philosophers including Raymond Williams, Antonio Gramsci, Terry
Eagleton, Roland Barthes, Jean Paul Sartre, Michel Foucault, Jean François Lyotard and
Jean Baudrillard in order to gain a better understanding of the social and historical
context from which this genre emerged.
By concentrating on the literary texts, I have explored readings which lead out into
an analysis of the broader philosophical, political and historical issues raised by the
Cuban revolution. Since it deals primarily with modes of deviance and notions of legality
and justice within the context of the modern state, detective fiction is particularly well
suited to this type of investigation. The intention is to show how this is as valid in the
Cuban context as it is in advanced capitalist societies where such research has already
been carried out with some success.
The thesis comprises an introduction, ten chapters and a conclusion. The chapters
are divided into three sections. Chapters 1 to 3 attempt a broad theoretical, historical and
socio-political analysis of the cultural reality within which the Cuban revolutionary
detective genre emerged. Chapters 4 to 6 analyse the Cuban detective narrative from its
inception in the early part of the twentieth century until the emergence of Leonardo
Padura Fuentes as the foremost exponent of the genre in Cuba after 1991. Chapters 7-
10 concentrate upon the work of Leonardo Padura Fuentes, offering a reading of his
detective tetralogy informed by the preceding discussion.
The contribution made by the thesis to knowledge of the subject is to build upon the
work of Seymour Menton and Amelia S. Simpson on the development of the Cuban
detective novel and to provide analyses of the pre-Revolutionary Cuban detective
narrative and the work of Leonardo Padura Fuentes for the first time in the English
language. The thesis concludes that the study of this popular genre in Cuba is of crucial
importance to the scholar who wishes to reach as full an understanding of the social
dynamics within that society as possible. In particular, it proves that Cuban detective
fiction provides a useful barometer of social change which records the shifts in the Cuban
Zeitgeist that have taken place over the past century
ChemInform Abstract: Ketenimines as Intermediates in the Hydrolytic Decyanation of α-Cyano-γ-lactones.
No full text
A expansão financeira do ciclo sistêmico de acumulação Norte-Americano e seu impacto na dívida externa da América Latina: o caso do Brasil
Get PDFTCC (graduação) - Universidade Federal de Santa Catarina. Centro Sócio-Econômico. Economia.0 curto horizonte temporal e espacial da maioria das explicações acerca da crise da divida externa que abateu os países da América Latina no final dos anos setenta é notável. Muitos autores se detêm nos próprios anos desta década com a pretensão de explicar a questão da divida externa. Outros focalizam a economia brasileira e, num segundo plano, a relaciona com as mudanças ocorridas no âmbito mundial. Algumas interpretações, mais raras, identificam a imposição das transformações da economia mundial sobre o território nacional de forma a apresentar o enorme crescimento da divida daquela década e as posteriores políticas destinadas ao seu pagamento como um processo subordinado a um movimento de caráter sistêmico. Apesar do avanço destas últimas, muitas vezes consistência de suas conclusões é tão limitada quanto seu horizonte temporal de estudo. Diante de tais considerações, o presente trabalho recorre ao modelo de análise desenvolvido por Giovanni Arrighi em sua obra "0 Longo Século XX" para propor uma nova interpretação da crise da divida externa latino-americana. A crise da divida externa vivida pelos países latino-americanos a partir da década de 1970 e as conseqüentes políticas macroeconômicas direcionadas ao seu pagamento são entendidas como um processo intrínseco à etapa de expansão financeira do que Arrighi denominou de Ciclo Sistêmico de Acumulação norte-americano. 0 estudo concentra-se no caso do Brasil e, tendo em vista sua própria estrutura social, descreve a conjuntura interna que contribuiu — porém não determinou — para a enorme expansão da divida externa durante a década de setenta
Síntesis de triazoles derivados de galactosa, lactosa y 2-(2-piridil) benzimidazol
Get PDFLos glicoconjugados ejercen funciones importantes en diversos procesos biológicos, así como inhibición frente enfermedades infecciosas y parasitarias. Los glicoconjugados de triazolio poseen moléculas que contienen un triazol unido a un carbohidrato, estos triazoles pueden encontrarse en la posición anomérica o en otra posición del carbohidrato, permitiendo funcionalizar a la estructura del mismo o bien para fungir como unión con otra molécula de carbohidrato. En este trabajo se presenta la síntesis de triazoles derivados de hexosas y 2-(2-piridil) benzimidazol, con el objetivo de emplearlos como sustratos para obtener complejos de cobre.Glycoconjugates exert important functions in several biological processes, as well as inhibition against infectious and parasitic diseases. Triazolium glycoconjugates have molecules containing a triazole attached to a carbohydrate. These triazoles can be found in the anomeric position or in another position of the carbohydrate allowing them to functionalize to the structure of the carbohydrate or to function as a linkage to another carbohydrate molecule. In this work we present the synthesis of triazoles derived from hexoses and 2-(2-pyridyl) benzimidazole with the aim of using them as substrates to obtain copper complexes
Síntesis de etinil estradiol y su aplicación en una reacción de ciclo adición catalizada por Cu(I)
Get PDFEl etinilestradiol es un esteroide común en medicamentos de terapia y regulación hormonal y contiene en su estructura un grupo alquino en el carbono 17 que permite llevar a cabo una reacción de ciclo adición [3+2] para la obtención de 1, 2, 3 triazoles. En este trabajo se describe una metodología alternativa para la obtención del etinilestradiol a partir de estrona mediante una reacción de Grignard empleando como nucleófilo al bromuro de etilinilmagnesio, este derivado se utilizó como sintón para la formación de un triazol hibrido compuesto de un esteroide y un azida derivada de carbohidrato (3-azida-1,2:5,6-diisopropiliden--D-glucofuranosa) bajo condiciones de térmicas clásicas. Los productos de reacción fueron caracterizados mediante espectroscopia de infrarrojo y resonancia magnética nuclear hidrogeno y carbono 13.Ethinylestradiol is a common steroid in therapy and hormone regulation drugs and contains in its structure an alky negro up at carbon 17th at allows to carry out a[3+2] cycloaddition reaction to obtain 1, 2, 3 triazoles. In this work we describe an alternative methodology to obtain ethinylestradiol from estrone by means of a Grignard reaction us ingethylinylmagnesium bromide as nucleophile.This derivative was used as a synthon for the formation of a hybrid triazole composed of a steroid and a carbohydrate-derived azide (3-azide-1,2:5,6-diisopropylidene-α-D-glucofuranose) under classical thermal conditions. The reaction products were characterized by infrared spectroscopy, hydrogen and carbon 13 nuclear magnetic resonance
Preparación de un plausible eje de rotaxano quiral aminoácido-esteroide
Get PDFRotaxanes are compounds that are made up of two submolecular components: a cyclic one (a ring) and a linear one (an axis) that threads the previous one and that, in addition, has bulky groups at their ends in order to keep both components intertwined. Another simple tool to keep this type of macrostructures anchored is through non-covalent bonds such as hydrogen bonds, coordination bonds with metal ions and aromatic π-π interactions, among others. In this work the rapid and quantitative synthesis of a conductive thread (chiral axis) composed of chiral molecules is reported, which give it excellent anchoring properties important for the synthesis of rotaxanes.Rotaxanes are compounds that are made up of two submolecular components: a cyclic one (a ring) and a linear one (an axis) that threads the previous one and that, in addition, has bulky groups at their ends in order to keep both components intertwined. Another simple tool to keep this type of macrostructures anchored is through non-covalent bonds such as hydrogen bonds, coordination bonds with metal ions and aromatic π-π interactions, among others. In this work the rapid and quantitative synthesis of a conductive thread (chiral axis) composed of chiral molecules is reported, which give it excellent anchoring properties important for the synthesis of rotaxanes
