ORGANIC CHEMISTRY, 5

Author: BAYÓ PUXAN NÚRIA.
Year: 2006.
University: BARCELONA.
Place of defense: FACULTAD DE QUÍMICA.
Place of preparation: PARC CIENTÍFIC DE BARCELONA.

Summary: Natural products are of great importance in the systems of prevention and healing of ailments and diseases of human beings. So about 50% of current drugs are based on natural products, and 80% of the world's population depends today on traditional medicine. The process of developing a new drug from a natural product is long and complex. The recent improvements and generally at each stage of the process, has led to a renewal in the interest of the pharmaceutical industry for new natural bioactive compounds. The chemical synthesis has a role in the process of developing a new drug: the chemical synthesis product bioactivo ensures the identity of the compound, as well as ensure the large-scale production to allow for the completion of clinical trials and meet the demands the pharmaceutical market. The introduction of the chemical in solid phase has been one of the most significant improvements in the area of chemical synthesis, allowing an exploration synthetic more quickly and efficiently. This change has been widely used by the synthesis of peptides and oligonucleotides, and especially relevant in obtaining depsipéptidos cyclical produced by microorganisms and interesting activity and interest as new drugs. Thus, in this view, has worked on the development of new solid phase synthesis of two depsipéptidos cyclical, sirengotoxina and tiocoralina, with a view to contributing in their therapeutic application. The sirenogotoxina is a lipononadepsipéptido cyclical produced by a pathogenic bacteria of the citrus trees he has shown an interesting activity against the Leishmania parasite. This draft has designed a drug peptide similar to the natural peptide that has the same structural elements and the configuration of the peptide chain. It has been obtained by an approximation in solid phase and through a strategy consistent with the synthesis of a natural product. This synthesis has been resolved obtaining aminoácidono proteinogénico well as its proper insertion into the chain. The tiocoralina is a peptide bicíclico symmetrical produced by a marine microorganism isolated from the soft coral, and that presents a potent antitumor activity as. This project has developed a synthetic analogue of the natural peptide more resistant plasma, azatiocoralina. Finally, it has been obtained by approximating natural product in solid phase. In this case, has also resolved the synthesis of two amino acids not proteà ¯ nogénicos, two N-methyl tanks. Finally, we have isolated new anti-tumor agents from marine sponges collected from the Australian coast in order to obtain new drugs as well as expanding knowledge in the process of developing a new drug.

Author: SALAS VICENTE JOSÉ.
Year: 2006.
University: POLITÉCNICA DE VALENCIA.
Place of defense: Dep. Quimica.
Place of preparation: Universidad Politécnica de Valencia.

Summary: This thesis explores the usefulness of reactions fotoquímicamente initiated in UVV for funcionalización particles. The experiments were conducted with particles smaller than the micron, but they can extend, qualitatively, to larger diameter particles. The chemical changes produced in the particles (insertion of oxygenated groups or chlorinated) have been identified and associated with the modification of some physicochemical property of particles (energy liaison particle / particle or stability in liquid suspensions). The experiments carried out during this thesis will, in future, the development of new areas of industrial application for the photochemistry in the region of the vacuum ultraviolet. Three different aerosol systems have been studied experimentally. For the chemical composition of the spray could classify as:-A spray of organic material with a high vapor pressure that shows a tendency to evaporation (anthracene). The use of radiation in the UVV funcionalización particles with high pressure steam was not feasible. The particles were anthracene evaporadas and partially oxidized. The oxidation of anthracene occurred in vapor phase and was followed by a heterogeneous condensation of the reaction products. The reaction products (more vapor pressure that the anthracene) condensaban on particles original and new condensation nuclei (secondary aerosol). An aerosol - polymeric materials (polystyrene) in an atmosphere "normal" (air). The irradiation of polymer particles in aerosols is a useful system for chemically modify.

Author: ELIAS I PERA XAVIER.
Year: 2006.
University: AUTÓNOMA DE BARCELONA.
Place of defense: FACULTAT DE CIÈNCIES.
Place of preparation: FACULTAT DE CIÈNCIES.

Summary: Reactions metátesis of dienos and eninos catalyzed by species carbénicas of ruthenium are powerful tools widely used by organic chemicals for the synthesis of a wide variety of products. The importance of the reaction of metátesis has been evident in the granting of the Nobel Prize in Chemistry 2005 to Chauvin, Grubbs and Schrock. The quest for more stable and active catalyst and the preparation of catalyst recycling efforts have attracted a large number of groups in recent years. Grubbs and Hoveyda have introduced carbenos N-heterocíclicos (NHC) and ligands estirénicos quelatantes for improved catalytic systems. One of the strategies used for the recovery and recycling of these catalytic systems is the anchor of the species to support homogeneous polymer insoluble organic polymers being the most common. Within the inorganic work are fewer and are anchoring a commercial silica, monolithic systems or silica mesoestructuradas. The more stable thermal, chemical and mechanical inorganic polymers and their high surface areas, making them attractive alternatives for the incorporation of covalent organic ligands and metal complexes. As an alternative to anchoring, the organic portion can join the inorganic matrix through sol-gel process, either by cogelificación a organotrialcoxisilano with tetraetoxisilano or by hydrolysis and polycondensation of organic precursors having two or more functions trialcoxisililo. The hybrids orgánico-inorgánicos derived silica sol-gel derived by experienced a boom in the last decade, with the development of organized systems in the presence of surfactants. Their use in the field of catalysis has been relatively little exploited. In this dissertation were synthesized five monomers different type Hoveyda, presenting groups trietoxisililo. The first is an equivalent of chelating ligand original Hoveyda which includes a chain space with an i carbamate group trietoxisililo. Other monomers are variations where the chain space includes a urea instead of carbamate. One structure contains a nitro group that should enhance their activity as catalitzador, while another is a derivative bisililado, which allows the preparació materials by the sol-gel process is not required for the addition of tetraetoxisilano ( TEOS). Moreover, the presence of a second string must also act by increasing the activity of the catalyst due to effects estéricos. Based on the different monomers produced hybrid materials have been synthesized by several procedures: by the sol-gel process using ammonium fluoride as a catalyst (cogelificación with TEOS in various proportions), in the presence of dodecilamina, serving as structuring agent and catalyst at the same time, in the presence of bromide miristiltrimetilamonio, surfactant which also acts as structuring, and in the case of derivative bisililado, also by sol-gel in the absence of TEOS. These monomers have been anchored to silica mesoestructurada MCM-41 and silica gel commercial. In some cases it has sililado the surface of materials prepared by reaction with hexametildisilazano, thereby eliminating the free hydroxyl groups of this size, and that it was thought that could affect the catalyst. All materials have been characterized through collaboration with the group of CEB Moreau and M. Wong Chi Man in the 'Ecole Nationale Superieure de Chimie de Montpellier' using different techniques: Nuclear Magnetic Resonance carbon-13 i silicon-29 solid-state (which allows check covalent binding between the ligand and the organic matrix silylated) measures adsorción - desorción nitrogen by the BET method (which determines the specific surface of the material as well as the distribution of pore diameter and volume), X-ray diffraction powder (determination of the possible structure of m 8 aterial) ea7, elemental analysis (amount of organic matter incorporated) and transmission electron microscopy (TEM). It is noted that the materials presented specific areas where major structural agents have been used and when the dilution of the organic part in the interior of the material is higher. The treatment of hybrid materials with carbenos of Grubbs of first and / or second generation has led to the appropriate catalysts supported. These have been tested in reactions metátesis intramolecular of dienos to get olefins di-, tri-and tetrasubstituidas, and also in metátesis a enino. We assessed the ability of these catalysts to be recycled in a number of successive cycles. The results obtained indicate that the materials treated with the catalyst of the second generation are the most effective and heterogeneous catalysts from sol-gel are most active and recycled better than those for anchoring to MCM-41 and silica trading . The synthesis of 1-(4-toluensulfonilo) -2.5 -dihidro-1H-pirrol has been made up to five consecutive cycles to most of the catalysts in times from 30 minutes to 8 hours depending on the case and the higher conversion 90% in the fifth cycle for some of the catalysts. Those materials containing monomer more like the chelating ligand original Hoveyda are those that give more capacity for recycling, while the most active are those containing the group electroatrayente nitro. Among the catalysts prepared by the sol-gel process prove to be the most active having a higher specific surface and greater dilution of ligand in its interior. The materials prepared from monomer bisililado without the addition of sol-gel presented, despite having a surface void, an activity comparable to the highly porous. The sililación the surface of certain materials has resulted in more active catalysts in general, but that is recycled worse. The synthesis of 1-(4-toluensulfonilo) -2.5 -dihidro-3-metil-1H-pirrol has been able to make up 5 cycles of catalysis, with times between 1.5 i 7 pm and conversions higher than 90% in the fifth cycle in some cases. These results are best described in the literature with Supported catalysts for this reaction. The synthesis of 3,4-dimetilo-1- (4-toluensulfonilo) -2.5 -dihidro-1H-pirrol has been achieved until 3 cycles with one of the catalysts, and 2 with the majority. These results constitute the first successful example of preparing this olefine tetrasubstituida with a supported catalyst, and the first case in which the catalyst is achieved reused with some success. In metátesis of enino 1-al liloxi-1 ,1-difenilo-2-propino have been achieved up to five cycles with most of the catalysts with higher conversion to 90% in the fifth cycle. The results represent the first example of restoring a catalyst in a reaction metátesis of eninos.

Author: PINACHO CRISOSTOMO FERNANDO RODRIGO.
Year: 2006.
University: LA LAGUNA.
Place of defense: INS. UNIVER. DE BIOORGA. ANTONIO GONZALEZ.
Place of preparation: INSTITUTO DE BIOORGANICA ANTONIO GONZALEZ, UNIVERSIDAD DE LA LAGUNA.

Summary: The marine toxins whose structures presents fused cyclic ethers or isolated, have aroused a great deal of interest in the scientific community not only for its socio-economic impact, but also because of its potent biological activity and structural complexity. Their scarcity in nature requires new synthetic methods for accessing these substances in sufficient quantities to undertake studies that reveal its mechanism of action and / or possible to develop drugs based on the structures of these compounds. Among the marine toxins are those whose most important structural feature is the presence of fused polycyclic ethers (skeleton type "ladder"). As an example we can cite the brevetoxina B, which was the first of its kind composed elucidated, being isolated from the dinoflagellate Gymnodinium breve. This body is responsible for so-called red tides, a phenomenon caused massive mortality of fish. Leveraging biogenesis postulated for this class of compounds, we developed a new methodology based on the reaction of Nicholas, where a convenient way of epoxide positioned in a chain carbon act as nucleofilo intramolecular. By varying the chain length succeed in obtaining good yields ring tetrahidropiranos di-and tri-sustituidos and rings oxepanos di-sustituidos. This approach also allowed us to perform the formal synthesis of (+) -muconina, natural product within the class of compounds known as acetogeninas. This family of products has attracted interest in the scientific community because of their potent anti-tumor activities. The (+) -muconina has been shown to have a significant in vitro activity against human tumor cells in the pancreas and breast. In addition to achieving the synthesis of a precursor advanced for the acquisition of (+) -muconina, conducted a study of structure-activity relationship, where intermediate synthesized were evaluated face of solid tumor cell lines human A2780 and SW1573. The good results obtained in this study allowed us to propose a structural simplification for the intermediate advanced synthesized.

Author: PARDO TALAVERA DAVID.
Year: 2006.
University: VALENCIA.
Place of defense: FACULTAT DE QUÍMICA.
Place of preparation: FACULTAD DE QUÍMICAS.

Summary: The present work has been undertaken the preparation of various terpenos bicíclicos with skeleton drimano, where the hydrogen H-9 is replaced with a fluorine atom. The synthesis of these drimanos fluoride has been carried out from ionona used as intermediate common to all of them a decalona fluoridated prepared from a -cetoéster through a fluorination reaction stereoselective with NFSi. This decalona fluoride has been used as sintón of the Rings AB for obtaining the various systems drimano fluoride that have been prepared. Beginning with the same number have developed synthetic routes for the preparation of similar fluorinated several drimanos natural biologically active. In particular, it has successfully completed the acquisition of 9 F drimenina, 9 F albicanol, acetate 9 F albicanilo and 9 F albicanal. There have also been examined various approaches to obtain similar fluorinated drimanos where this is a grouping 12 carbonílica, -insaturada present in a large group of drimanos natural relevant biological properties, such as compounds poligodial and cinamólido. Unfortunately, this goal has not been able to achieve in a completely satisfactory due to reactivity unexpected problems which have arisen in the last stages of the synthesis and can be attributed to the presence of fluorine atom. During the exploration of these approaches have yielded various systems drimano fluorinated related, also observed interesting aspects of the reactivity of fluorine, some of them with no known history, and that confirm the difficulty of predicting the reactivity of organic molecules fluoride. In order to assess the influence of fluorine atom in the reactivity, biological activity and structural features of these systems drimano fluoride has been carried out also preparing systems drimano not fluorinated for using, wherever possible, synthetic same strategy followed for the preparation of fluorinated system. Some of the differences in reactivity observed between systems fluorinated and non-fluorinated consistent with the predictable electronic and structural change occurring in the different reactive positions by the presence of fluorine atom in the position shown, such as, for example, the slowdown that can be seen in the epoxidación a double bond exometilénico or in the process of oxidation of a group hidroximetileno. However, the behavior observed in the reactivity of any of the schemes fluorinated is not readily explicable. Perhaps the most striking examples in this respect are the inertia of a hydroxy -butirolactona to experience the reaction of dehydration or opening a grouping oxiránica to corresponding alcohols alílicos, transformations that occur without difficulty in non-fluorinated similar systems. It has been observed for the first time the reaction replacement rate SN2Â 'fluorine alílico catalysed Pd (0), via formation of a complex of palladium 3 alílico. We have carried out various tests of biological activity with a substantial number of products prepared to assess the change in activity that produces the presence of a fluorine atom in its structure, and have also conducted trials of anti-tumor activity . Although so far has not been able to complete a study Crystallographic to evaluate the influence of fluorine atom on the crystalline structure of the compounds prepared, the preliminary data that are available show that in the absence of strong interactions, such as bridges hydrogen produced by the presence of clusters hidroxílicas, fluorine atoms determine the crystalline state of organization of these substances.

Author: ATIENZAR CORVILLO PEDRO ENRIQUE.
Year: 2006.
University: POLITÉCNICA DE VALENCIA.
Place of defense: Universidad Politécnica de Valencia.
Place of preparation: Universidad Politécnica de Valencia.

Summary: The wall carbon nanotubes only (SWNT) presents a series of properties (nano diameter, length until centimeters high and variable conductivity in the range driver / semiconductor, high resistance to breakage, etc.). Materials that make them very promising for applications in nanotechnology. In order to introduce in response to stimuli photochemical nanotubes front, our thesis has been to prepare a series of derivatives of single wall nanotubes that have been funcionalizados through covalent bonds, either at the tips of nanotubes (groups n pentil, pirenil, viológeno) or on the walls (groups piridil) carbon nanotube. Given the high absorbance of the SWNT in the first chapter demonstrated that it is possible to apply diffuse reflectance techniques for solid materials based on carbon nanotubes when these are incorporated into silica mesoporosas. By diffuse reflectance properties identified fotofísicas mixtures of SWNT funcionalizados with pyrene derivatives dispersed in silica. This inorganic oxide serves to increase the reflectance of the whole. Alternatively by introducing groups n-pentilo have been prepared based materials SWNT to be properly dispersed in organic solvents, particularly in acetonitrile, which allows her study by transmission techniques. It was also studying carbon nanotubes funcionalizados units viológeno that are heavily aceptoras electron. The funcionalización on the walls was carried out through an addendum [3 +2] to give rise to pirazolinas groups piridilo that are capable of forming complex with zinc porphyrin and produce a transfer of energy between two or electronic components. Finally, we have developed prototypes of functional solar cells based SWNT funcionalizados with viológeno observed that the activity of this photovoltaic cell is higher than that presents a cell similar swnt without funcionalizar.

Author: PEÑA GONZALEZ CARMEN.
Year: 2006.
University: OVIEDO.
Place of defense: FACULTAD DE QUIMICA.
Place of preparation: FACULTAD DE QUIMICA.

Summary: Compounds polinitrogenados are a very important group in the field of supramolecular chemistry. The ability to modulate their properties through pH leads to many applications such as complexation of anions and cations, and catalysis processes of molecular recognition. In this report, structured into three chapters, describes the synthesis of new receivers polinitrogenados enantiopuros different in nature and their application in different areas of molecular recognition. The first chapter has a methodology that allows selective alkylation of trans-ciclohexano-1 ,2-bis (sulphonamide). Likewise, have studied the factors that influence the selectivity of the process. The second chapter has used the methodology developed in the first chapter to carry out the preparation of a azamacrociclo optically active as well as various polyamines enantiopuras chain open. In addition, it has assessed the ability of these polyamines stereoselective manner to interact with DNA. The third chapter has been carried out the design and synthesis of a new receptor type piridindi (carboxamide) via a method quimioenzimático. It has evaluated its ability to act as an agent of chiral solvatación for determining the purity enantiomeric carboxylic acids by nuclear magnetic resonance. Likewise, it has made a thorough study of the structure of the receptor in solution and interaction with the substrates. Thus, it has proposed a model that explains the complexion of the different types of acids. Moreover, there had been a series of similar receptor initial study the influence of the structural characteristics in the process of solvatación chirality of carboxylic acids racémicos. Some of the results that constitute this report are listed in the bibliography following: "Solvent dependent alkylation of a bis (sulfonamide) for the synthesis of a DNA-binding chiral polyamine. C. Pena, I Alfonso, NH Voelcker, and V. Gotor, Tetrahedron Lett. 2005, 46, 2783. "Conformationally biased selective alkylation of trans-Cyclohexane-1 ,2-bis (sulfonamide) assisted by solvent-tuned protecting groups: Applications to the synthesis of a large optically active polyazamacrocycle." C. Pena, I Alfonso and V. Gotor, Eur. J. Org. Chem., 2006, 3887. "Synthesis and stereoselective DNA binding abilities of new optically open chain polyamines. C. Pena, I Alfonso B. Tooth, NH Voelcker, and V. Gotor, J. Org. Chem., 2007, in press, DOI: 10.1021/jo0619837

Author: ANDINA MENENDEZ FACUNDO.
Year: 2006.
University: OVIEDO.
Place of defense: FACULTAD DE QUIMICA.
Place of preparation: FACULTAD DE QUIMICA.

Summary: This report, which comes within the scope of Chemical Organometálica, deals with the study of the reactivity of different carbenos Fischer, a b-insaturados. The contents of the same has been divided into two chapters reflect the type of complex used and the reaction to which they are subjected. The first chapter has developed an experimental protocol that allows easy access to 4-aril-3 ,4-dihidrocumarinas through the reaction between alquenilcarbenos Fischer and acetals of cetena. This process has been optimized to obtain these interesting compounds at multigramo. It also describes the transformation of vinilidenos chromium (0) in alquinos, done that, as of this writing, is unprecedented for group metals 6. The second chapter investigates the behavior of different types of alquinilcarbenos Fischer previously designed when they are subjected to various reactions cicloadición. As a result obtained several sequential processes dependent on the structure of the original complex. From the point of view synthetic reactions described in this chapter provide derivatives of naphthalene, fenantreno and benzoisoxazol and policíclos of high structural complexity and inaccessible by other methods.

Author: TORRE GONZALEZ OLIVER.
Year: 2006.
University: OVIEDO.
Place of defense: FACULTAD DE QUIMICA.
Place of preparation: FACULTAD DE QUIMICA.

Summary: In recent years there has been a spectacular growth in the use of methods biocatalíticos for the preparation of compounds with high added value, and the biotransformations have allowed access to compounds of interest from the point of view of the industrial sector through selective processes, low cost and produce lower levels of pollution that chemical methods to date. In this report, esructurada in four chapters, was conducted by the synthesis quimioenzimática of different organic compounds using lipases as biocatalysts, enzymes that have shown great selectivity of conventional processes and in turn a high catalytic promiscuity that has been studied in detail. The first chapter has conducted a study of the parameters that affect the reaction of aminólisis catalysed by Candida antarctica lipase B from methyl acrylate and the N, N-dimetil-1 ,3-propanodiamina, optimizing the conditions for to obtain the corresponding acrylamide, sintón important in the preparation of polymers. The results are reflected in the publication: O. Torre, V. Gotor-Fernández, I. Alfonso L. F. García-Allés, V. Gotor, "Study of the chemoselectivity in the aminolysis reaction of methyl acrylate catalysed by lipase B from Candida antarctica", Adv. Synth. Catal. 2005, 347, 1007-1014. The second chapter has studied the catalytic power of some lipases, particularly Candida antarctica lipase B, in addition reactions Michael type between different primary or secondary amines and acrylonitrile or metacrilonitrilo. Some of the results obtained in this aparatado have been published in: O. Torre, I. Alfonso V. Gotor, "Lipase catalysed Michael addition of secondary amines to acrilonitrile" Chem. Commun. 2004, 1724-1725. The third chapter has been carried out enzymatic resolution derivatives 3-amino-3-fenil-propanol in order to obtain precursors suitable for the preparation with good yields and high wealth optical (S) -Dapoxetina composed used as therapeutic agent in the treatment of various diseases. Some of the results obtained in this chapter seem reflected in the publication: O. Torre, V. Gotor-Fernández, V. Gotor, "Lipase-catalyzed Resolution of chiral 1,3-aminoalcohols. Application in the asymmetric synthesis of (S) -Dapoxetine" Tetrahedron: Asymmetry 2006, 17, 880-886. Finally, the fourth chapter of this report have synthesized a large number of 4-cloro-aminopiridinas enantiomericamente pure through a method quuimioenzimático using biocatalysts as Candida antarctica lipase from Pseudomonas cepacia or .. The results have been submitted for possible publication: O. Torre, E. Bust, V. Gotor-Fernández, V. Gotor, "Enzymatic preparation of novel aminopyridines using lipases in organic solvents," Adv. Synth. Catal. Envoy.

Author: BOULIFI NOUREDDIN EL.
Year: 2006.
University: COMPLUTENSE DE MADRID.
Place of defense: FACULTAD DE CIENCIAS QUÍMICAS.
Place of preparation: FACULTAD DE CIENCIAS QUÍMIAS.

Summary: Studies conducted by D. Norueddin El-Boulifi in his Doctoral Thesis have identified the structural factors that control the competition between the reaction oxa-di- *- methane and processes Norrish Type I, irradiation triplete compounds carbonílicos beta, gamma ,*,*- unsaturated. The lack of reactivity differ *- methane from any of the compounds studied can be overcome by transforming them into their corresponding oxime acetates. The products obtained are precursors components ciclopropánicos in pyrethrins and pyrethroids. However, the most important result has been demonstrating for the first time the influence of the energy of sensitizer hat trick on the course of the reaction. The study shows that compounds previously desactivos as compared with non-reactive processes differ *- methane experiencing this reaction when used with sensitizing energies close to the hat-trick of alqueno acceptor. This result radically modifies some of the concepts that seemed firmly on Organic Photochemistry and open new lines of research in this field. A preliminary communication of the same has been published in Angew. Chem Int. Edit.

Author: FERNANDEZ BACHILLER M. ISABEL.
Year: 2006.
University: COMPLUTENSE DE MADRID.
Place of defense: FACULTAD DE CIENCIAS QUÍMICAS.
Place of preparation: FACULTAD DE CIENCIAS QUÍMICAS, UNVIERSIDAD COMPLUTENSE DE MADRID.

Summary: During the development of this Doctoral Thesis has carried out the design, synthesis and evaluation of new biological products multifunctional able to act on several targets of therapeutic interest in Alzheimer's disease, such as inhibition of AChE, the antioxidant capacity and inhibition of Aggregation of beta-amiloide. There have been different families of hybrid molecules, combining in a single structure several biological properties of interest to Alzheimer's, being a good prototype for the development of new drugs not only be able to alleviate the symptoms of the disease, but they can stop the process neurodegnerativo.

Author: PÉREZ IBÁÑEZ PALOMA.
Year: 2006.
University: COMPLUTENSE DE MADRID.
Place of defense: FACULTAD DE CIENCIAS QUÍMICAS.
Place of preparation: INSTITUTO DE CIENCIA Y TECNOLOGÍA DE POLÍMEROS, CSIC.

Summary: The dissertation deals with the synthesis and characterization of a new entrecruzante formed by amino acids and hydrogels termosensibles of pNIPA entrecruzados with him. We have also prepared systems macropororsos by criopolimerización using these monomers. There has been an evaluation of systems hydrogels for implementation as biomaterials. This has been characterized properties termosensibles of these systems and submitted for possible application systems through various experiments on cells and the process degradativo since the entrecruzante synthesized is biodegradable. This has been used capillary electrophoresis coupled to a detector masses identified all degradation products as well as the formation mechanism of each of them.

Author: ORTEGA MARTÍNEZ JOSE ANTONIO.
Year: 2006.
University: BARCELONA.
Place of defense: FACULTAD DE QUÍMICA.
Place of preparation: FACULTAD DE QUÍMICA (UNIVERSIDAD DE BARCELONA).

Summary: It has perfected the synthesis of nucleoside analogues cytidine Fenoxazina and Clamp amino - guanine and their incorporation into chains oligonucleotídicas. At dissolution, these chains are unstable compared to the light but can be kept in solid state and low temperature for prolonged periods. The duplex DNA oligonucleotides formed by incorporating fenoxazina with a nucleus base pirimidínica at position 5 'contiguous are more stable than the natural, while in the duplex where nucleobase shown by 5' is a purínico the increase is null or nonsignificant. On the contrary, all duplexes formed by ligonucleótidos with bracket G are considerably more stable than natural ones, with a strong dependence on the degree of sequential stabilization that produces the modification. Overall, the stabilization is greater when the nucleobase shown at 5 'is a pyrimidine. It seems that the nucleobases modified B alter the conformation of DNA or interactions occurring ammonium group of the bracket with the groups opposing phosphate chains. The duplex PNA-DNA that chain NAPA contains a bracket G show, in the cases reviewed, a behavior similar to that of the duplex DNA.

Author: TORRENT PALOMERAS ANNA.
Year: 2006.
University: GIRONA.
Place of defense: FACULTAD DE CIENCIAS.
Place of preparation: UNIVERSITAT DE GIRONA.

Summary: This thesis has focused on the synthesis and structural characterization of new types of macrociclos nitrogen fifteen, twenty and twenty five members, which contain triple and double bonds and different units arílicas in its structure. All these macrociclos have been prepared from arilsulfonamidas and corresponding 1,4-dihalobuteno or 1,4-dihalobutino compounds commercially available or easily prepared. The optimization of the preparation of the intermediates has opened a way for the efficient synthesis of a wide variety of macrociclos nitrogen polyunsaturated. They also have developed a new type of complex palladium (0) chiral, stable air and moisture, with macrocicles nitrogen polyunsaturated fifteen members. These complexes of palladium (0) have been prepared by an exchange of ligands using as a source of palladium Pd (PPh3) 4 or Pd2 (dba) 3 in the presence of corresponding macrocycle. It has conducted full characterization by NMR spectroscopy and X-ray diffraction. These complexes are the first complex paladio-alquino described in the literature with a cyclical ligand. Finally, we have studied the reactivity of different macrociclos synthesized. It has conducted a study of the reaction of cicloisomerización of macrociclos fifteen members. The reaction was carried out with different catalysts observed that the catalyst of Wilkinson of rhodium (I) is the one who has given more successful. The same reaction has been studied with macrociclos higher order of twenty and twenty five members. There has also been an introduction to the study of the mechanism of such reactions through a mass spectrometer with electrospray ionization, and how it has also been an initial study of the reaction of cicloisomerización enantioselectiva.

Author: FORMOSA MÁRQUEZ XAVIER.
Year: 2006.
University: BARCELONA.
Place of defense: FACULTAD DE FARMACIA.
Place of preparation: FACULTAD DE FARMACIA.

Summary: It has conducted the synthesis and pharmacological evaluation of two new families of acetylcholinesterase inhibitors of dual-binding site, heterodímeros huprina-tacrina and heterodímeros donepezilo-tacrina. The pharmacological tests have shown that these compounds possess an affinity inhibitory potency and remarkably enhanced respect to the model compounds, which presents them as interesting candidates for drugs anti-Alzheimer. In parallel, as a result of some resutlados unexpected obtained in the synthesis of heterodímeros donepezilo-tacrina, have been carried out some additional studies based on the synthesis, purification and characterization of various compounds espiropolicíclicos complexes esteroquímica on clearly defined, obtained reaction by multi indanona and aldehydes as product line, designed to deepen the effect of substitution in the course of reacicón, and incidentally, with the help of methods químico-teóricos, aimed at proposing a definitive mechanism for this interesting reaction .

Author: MORMENEO JULIÁN DAVID.
Year: 2006.
University: BARCELONA.
Place of defense: FACULTAD DE QUÍMICA.
Place of preparation: INSTITUTO DE INVESTIGACIONES QUÍMICAS Y AMBIENTALES DE BARCELONA (CID-CSIC).

Summary: The esfingolípidos compounds are widely distributed in eukaryotic cells main part of biological membranes. Although initially considered purely structural components membrane, currently known their involvement in different functions such as regulating cell growth and death. In this sense, these compounds are being investigated in diseases with high significance, such as cancer or AIDS. The work done in this dissertation is based on the synthesis of analogues esfingolípidos, focusing on the development of new antifungal agents given the high importance that these drugs are also in the present context. Families have been prepared compounds similar to fitoesfingolípidos present mostly in minority fungi and mammals. These compounds have a basic structure of (2S, 3S, 4R) -2-amino-octadecan-1 ,3,4-triol. The analogues synthesized differ from the naturally occurring compounds in the functional groups in position C1 (hydroxyl amine or Azides), in groups acilo employees for the training of amides in position C2 as well as the tereoquímica of centers estereogénicos in C3 and C4. The synthesis used to obtain these compounds was based on the reacicón of dihidroxilación asymmetric Sharpless on olefins prepared from a sinton chiral derived from L-serina. In addition, it was studied reactions ciclación intramolecular, preparing two new similar to the Jaspina B, an alkaloid isolated from marine sponges with high cytotoxic activity versus human carcinoma cells. All compounds were initially tested as inhibitors of the growth of Saccharomyces cerevisiae and a later stage, in front of other filamentous fungi and yeast, including species of the genus Aspergillus and Penicillium. In the case of a group with similar amide in a position C2, generally known as fitoceramidas, the survey looked at in vitro inhibitory activity of the enzyme ionositolfosfoceramida synthase, which is essential for cell viability in fungi and not present in humans. In parallel, assessed cytotoxic activity of all molecules obtained versus human cells A549 carcinoma. The results have identified two new compounds of these families can completely inhibit the growth of all species of fungi studied concentrations in the range of low micromolar. This effect was selective in the structure and estereoquímica of these compounds. In addition, it has been observed that the cytotoxic activity of the Jaspina B is a necrotic. In this group of molecules, it is worth noting that chemical change in the configuration in C3 and C4 dropping to ten times their activity, which could involve specific effects of Jaspina B on cellular structures.

Author: MONGE FERNÁNDEZ DAVID.
Year: 2006.
University: SEVILLA.
Place of defense: UNIVERSIDAD DE SEVILLA.
Place of preparation: FACULTAD DE QUÍMICA.

Summary: In this dissertation have addressed different aspects of asymmetric catalysis. On the one hand the short, the study of the structural and catalytic activity of new metal complex [Pd (II) and Rh (I)] with mixed ligands C / S chiral based carbenos N-heterocíclicos and tioéteres.Los complexes of cationic Pd (II) have submitted activity as a catalyst for the reaction of replacement alílica, reaching enantioselectividades of 91%. Moreover, we have developed catalytic systems for formilación / cianación enantioselectiva equivalent enoato based on the concept of "umpolung. The catalytic activation of hidroxienonas through Zn (OTf) 2/t-BuBox has allowed the conjugate addition of 1-metilenaminopirrolidina with good performance and enantioselectividad (up to 84% ee). Evidence supports an experimental model based on a share key contraión triflato to exercise control over the geometry of complex catalizador-sustrato through a bridge hydrogen OH-OTf. The activation organocatalítica of alquilidén glioxilatos through tioureas chiral from aminoindanol (aminoalcohol commercially available in two forms enantioméricas) has enabled the conjugate addition of 1-metilenaminopirrolidina with good performance and enantioselectividad (up to 80% ee). Experimental evidence suggests a course of action bifuncional catalyst, through participation of the NH acids and free hydroxyl group. La simplicidad operacional de este procedimiento y la alta versatilidad de los aductos confieren a esta aproximación una gran utilidad para la síntesis de compuestos ópticamente activos. The potential of the methodology is illustrated by the synthesis of (R) -2-metilsuccinato Dimethyl composed with insulinotropic activity.

Author: CORDEIRO MACHADO ALESSANDRA.
Year: 2006.
University: COMPLUTENSE DE MADRID.
Place of defense: FACULTAD DE FARMACIA.
Place of preparation: FACULTAD DE FARMACIA.

Summary: She discussed the particular reactivity introducing a new enamina cyclical derived from 1,2-O-Isopropilidén-alfa-D-xilofuranosa synthesized in our laboratory. This work has been reflected in three scientific publications in high impact in the field of medical and organic chemistry and be part of other publications that are currently under preparation. The resutlados obtained are divided into five chapters. Destacándose: 1-generation molecular diversity from a enamina cyclical derived from 1,2-O-isopropilidén-alfa-D-xilofuranosa. 2-Discovering the particular reactivity of a hidroxitríciclo nucleoside synthesized in our laboratory that lead to condensation aldólida acetone. 3-Summaries of policiclonucleósidos and tiofenilglicósidos by reaction glicosidación from a common precursor. 4-Summaries of new 5'-aminoribonucleósidos Tangled in position 3 'sugar. 5, - Assessment of the compounds obtained for different biological targets.