ORGANIC CHEMISTRY, 4

Author: FERRANDO RUANA FRANCESC.
Year: 2005.
University: BARCELONA.
Place of defense: FACULTAD DE FARMACIA.
Place of preparation: FACULTAD DE FARMACIA - UNIVERSIDD DE BARCELONA.

Summary: This Doctoral Thesis is in the context of reactions intramoleculares radicals 2-indolilacilo and is acting in accordance with the original objectives for both sides. The first part focuses on the ciclaciones radicals 2-indolilacilo able reductive using alquenos as aceptores radicalarios for obtaining structures that are part of natural products and other bioactive compounds. In this context has been achieved: 1 - The development of a new procedure for annulment indólica that accesses ketones cyclical 1,2-fusionadas with indole. 2 - The total synthesis of alkaloid (+-)- guatambuina and synthesis of alkaloid olivacina. The second part is in the context of reactions intramoleculares radicals 2-indolilacilo on aromatic systems. The main achievements in this part are: 1 - The ciclación radicals 2-indolilacilo on benzene ring in a position not reductive (n-Bu6Sn2-h) to efficiently indolil feil ceeonas tetracíclicas. 2 - The ciclación regioselectiva radicals 2-indolilacilo on piridinas able not reductive (n-Bu6Sn2-h) to indolil 4-piridil ketones tetracíclicas. The effectiveness of this protocol radicalario allows easy access to elipticina quinones. 3 - The ciclación radicals 3-(3-quinolil9metilo-2-indolilacilo able reductive (TTMSS-AIBN) to pentaciclos related calotrixina, the state of oxidation of which varies depending on the type of replacement nitrogen indólico. important role in the reactions of AIBN replacement homolítica aromatic.

Author: CÓRDOBA GAZÓLAZ RUBÉN.
Year: 2005.
University: COMPLUTENSE DE MADRID.
Place of defense: FACULTAD DE CIENCIAS QUÍMICAS.
Place of preparation: FACULTAD DE CC. QUÍMICAS.

Summary: The dissertation has focused on the following aspects: Looking for compounds with potential activity antiangigénica through the synthesis of structural analogues of aeroplisinina-1. Studies of the reactivity of cyanide ion in 6-espiroespoxiciclohexadienonas. Summaries of OTMS-cianhidrinas using ammonium salts and fosfonio as catalysts in the reaction of TMSCN with compounds carbonílicos. Reactions cianometilsililación catalysed Bu4NCN compounds carbonílicos with a center estereogénico preexisting (alfa-hidroxicetonas and alpha beta-epoxicetonas).

Author: RUIZ GÓMEZ GLORIA.
Year: 2005.
University: ALMERÍA.
Place of defense: UNIVERSIDAD DE ALMERÍA.
Place of preparation: UNIVERSIDAD DE ALMERÍA.

Summary: Reactions desaromatización through ciclación anion intramolecular on aromatic substrates activated groups electrón-atrayentes constitute an interesting methodology to access various systems heterocyclic easily. Clusters fosfinamida and fosfonamida are able to activate functions to a system aromatic front of the desaromatización. The metalación of N-alquil-N-bencildiarilfosfinamidas and arilfosfonamidas acíclicas with s-BuLi to -90 Â ° C in THF promotes desaromatización one of the Rings P-arilo with excellent performance, regional and diasteroselectividad. The capture of the species anionic litiadas with different electrófilos (sources protonación, alkylating agents, agents S-metilantes, aromatic and aliphatic aldehydes, olefins electrófilas) leads to new systems bicíclicos and phosphorus funcionalizados with tricyclic structure azafosfol. This process is equally effective on N-metil-N- (4-metoxibencil) and N - (2-furilmetil) -M-metildifenilfosfinamidas. The optimum reaction involving in some cases competition cosolvent different temperatures and reaction variables. The study of the phase litiación in the case of a dinaftilfosfinamida and fenilfosfonamida through testing and marking isotope deuterium measures magnetic resonance multinuclear solutions, has identified the type of anion precursor compounds azafosfólicos finally obtained. The methodology tuning on diarilfosfinamidas has spread to bisfosfinamidas. The process is more complex than in derivatives monofosforados. In these cases are accessed structures bisazafosfólicas as forms aquirales meso and racemates, and dominated the first on the latter. Changes made on azafosfoles obtained through ciclación anion intramolecular have demonstrated the feasibility of the catalytic hydrogenation reactions and cicloadición of Diels-Alder on fragments ciclohexadiénicos generated in the process of desaromatización. The substructure heterocíclica has been modified by up carboxylic acid oxidation of aromatic substituents on the carbon azafosfol adjacent to the nitrogen, and through the solvólisis liaison fósforo-nitrógeno under acidic conditions. The overall results are summarized in synthetic development of a methodology for the preparation of acids and esters gamma-aminofosfínicos or fosfónicos with different levels of funcionalización and conformational restrictions. Tests carried out on the cytotoxic activity hetero synthesized have shown a good ability to inhibition compared to the growth of various cancer cell lines at micromolar

Author: PÉREZ BALDERAS FRANCISCO MANUEL.
Year: 2005.
University: GRANADA.
Place of defense: FACULTAD DE CIENCIAS.
Place of preparation: FACULTAD DE CIENCIAS.

Summary: We have developed three new strategies for the synthesis of neoglicoconjugados which are based on different reactions key to the union of residual sugar to various types of scaffolding. Reactions keys are employed here: Reaction cicloadición 1,3-dipolar between oxide nitrile and a alquino leading to the formation of a isoxazole, reaction cicloadición 1,3-dipolar between an azide and an alquino for obtaining in addition reaction of triazole and Michael type between a vinyl sulfone and an amine. Additionally be used glicopiranosil vinilsulfonas for glicosidación protein chemistry. Cycloaddition 1,3-dipolar oxides nitrile and alquinos: The prelude to carry out such reaction cicloadición is effective synthesis of the corresponding oxides nitrile. As such nitrile are unstable oxides will be obtaining the same situ in the presence of a alquino. We have succeeded in synthesizing both oxides nitrile derived from sugar as scaffolds containing several remnants oxides nitrile from nitro compounds or oximes. The reaction of oxides nitrile with alquinoazúcares or polialquinos can obtain homo-and hetero-neoglicoconjugados divalent and multivalent that contain both O as C-glicósidos. Major conclusions were obtained dela influence of the structure of the same on their properties by inhibiting the study of the binding affinities of these neoglicoconjutados with lectin. Cycloaddition 1,3-dipolar of Azides and alquinos: The reaction between Azides and alquinos in the presence of salts Cu (II) leads so regioselectiva the corresponding triazole 1,4-disustituidos. The use of such reactions can be useful for the synthesis of neogliconjungados, however conditions used at the moment for such synthesis does not allow the collection of such compounds. To achieve these neoglicoconjugados has conducted the study of other alternatives that reaction conditions can be very useful when reagents are not soluble in aqueous solvents. Thus, the use of salts of Cu (II) or soluble organic solvents and possible irradiation with microwave synthesis systems containing several units traioles with high yields and short reaction times which has enabled us to demonstrate that the cicloadiciones 1, 3-dipolar of Azides and alquinos constitute an adequate method for the synthesis of neogliconjugados multivalent. The study of the affinity of these neoglicoconjugados by lectin confirms that the structure of genetic neoglicoconjugados has great influence on the inhibitory properties of these neoglicoconjugados. Moreover, cicloadiciones 1,3-dipolares of Azides and some have also proved very useful in the synthesis of other complex systems such as bis-ciclodextrinas, mixed systems calixareno- (bis-ciclodextrina) and bis (crown ether) . Reaction glicosil vinilsulfonas and amines: vinyl sulfones have often been used for addictions Michael type with amines, alcohols and thiol, however, have never been used for the synthesis of neoglicoconjugados. The prelude to develop this methodology involves the synthesis of the corresponding glicopiranosil vinilsulfonas from sugars what has been done in a simple and efficient manner. It has conducted an exhaustive study of the reactivity of these glicpiranosil vinilsulfonas as aceptores Michael face various amines which shows that it is possible to modulate the reactivity of the primary amines by proper choice of estequimetría of reagent and conditions reaction so that you can get the pure product of addition 1:1 or adding 2:1 vinilsulfona-amina primary. This methodology has yielded homoglicoconjugados and heteroglicoconjugados. Glicosidación protein: It describes for the first time a new procedure for obtaining neoglicoproteínas based on the reactivity of glicopiranosil vinilsulfonas. As enzymes model has been used lysozyme and taumatina l 8 as cuale 40d s have been treated with glucopiranosil vinilsulfona at room temperature and pH 7.7. In the case of lysozyme have been able to isolate a monocrystals lysozyme amended. The results prior diracción X-ray shows that has taken place ligación chemical remnants of four sugar to the protein chain. This reaction presents the advantage over other procedures glicosidación protein that is not necessary the addition of reagent to any part of the glicopiranosil vinyl sulfone and that the conditions of reaction are comaptibles with nature biological proteins.

Author: MARTINEZ REDONDO ALEJANDRO.
Year: 2005.
University: COMPLUTENSE DE MADRID.
Place of defense: FACULTAD DE CIENCIAS QUÍMICAS.
Place of preparation: FACULTAD DE CIENCIAS QUÍMICAS.

Summary: This Doctoral thesis focuses on the chemical modification of bitumen, through its reactivity with different functional features. The study concluded the amendment has allowed the most reactive. In a second part has been performed the synthesis of derivatives of furfuraldehyde, within a few steps of synthesis has been studied and their ability to amend certain properties of bitumen.

Author: Suárez Ordóñez Rosa María.
Year: 2005.
University: A CORUÑA.
Place of defense: Facultad de Ciencias.
Place of preparation: Facultade de Ciencias.

Summary: In the first part of this Doctoral Thesis explores the diastereoselectividad a conjugate addition reaction in aqueous media, discovered by Prof.. JL. Fight in 1986 and employs Zn and Cul, and the action of ultrasound. For this study, we used iodides of rent aquirales, primary, secondary and funcionalizados and systems carbonílicos alfa-beta-insaturados cyclical as acyclic. The chiral compounds carbonílicos alfa-beta unsaturated have utlizado both cyclic and acyclic systems. Compounds carbonílicos alfa-beta-insaturados cyclic have allowed us to study the diastereoselectividad at the stage of protonación of enolato intermediate. In addition reactions of conjugated to metilendioxolanonas chiral we found that the diasteroselectividad is high, while for metilenoxazolidinonas chiral the estereoselectividad depends on the group protector of nitrogen. In addition, we used products addition conjugated in the synthesis of alfa-aminoacidos enantioméricamente cigars. Compounds carbonílicos alfa-beta unsaturated acyclic gama-oxigenados tested have enabled us to determine the diastereoselectividad at the stage of adding nucleófila carbon beta. We noticed that diastereoselectividad in this case depends heavily on the geometry of conjugated double bond system. In general, we found that the results obtained in all cases support the mechanism proposed by Prof.. J.-L. Luche. The second part of the thesis is an approximation to the synthesis of Neomarinona, a natural product that provides marine-derived cytotoxic activity and antibiotic. In this work we have synthesized metil-Neomarinona through a synthetic route mixed with a linear portion and the other end converged, in a total of 10 stages and the overall performance of 3%. As key stages, we can highlight the synthesis of the intermediate carrier in the chain terpénica which has a quaternary center, and the reaction of Diels-Alder regioselectiva through which we have built the skeleton naftofuránico compound

Author: REVIRIEGO PICON FELIPE.
Year: 2005.
University: COMPLUTENSE DE MADRID.
Place of defense: FACULTAD DE CC. POLÍTICAS.
Place of preparation: INSTITUTO QUÍMICA MÉDICA C.S.I.C.

Summary: It has synthesized a new series of azaésteres crown 1H-pirazol protón-ionizables of 26-and 39 members funcionalizados groups NR type alquílico, aromatic or groups fluoróforos. The structures have been established on the basis of analytical and spectroscopic data of MS (FAB +), IR, 1HRMN, 13C NMR. In addition, by calculating the minimum energy conformations of taking into account the relative position syn or anti - that can take substituents in the NR macrocyclic cavity. Some diazatetraésteres crown of 26 members asilan as salts internal dipirazolato sodium whose structure has been identified by analytical methods, and spectroscopic techniques diracción X-ray Using these salts as a starting material, have been carried out studies complexation with hidrocloruros or sulphates amines psychotropic structure afetamínica in DMSO solution using NMR techniques and evaluated the stability constants of the complexes dipirazolato ammonium resulting techniques electrochemical. Taking as a model the hydrochloride dextrometanfetamina (speed) (Meth) and a salt pirazolato sodium character ambifílico, and using techniques potenciométricas, has been calculated estequiometría and constant effective aqueous complexation at physiologic pH. On this basis, using mice NIH / Swiss has evaluated the effect of this salt on the neurotoxic effects in vivo induced Meth short - and long-term ambient temperature (20-22Â ° C) and he induced mortality rate Meth temperature more than 22Â ° C.

Author: CORNEJO IBERGALLARTU ALFONSO.
Year: 2005.
University: PÚBLICA DE NAVARRA.
Place of defense: DEPARTAMENTO DE QUÍMICA APLICADA.
Place of preparation: DEPARTAMENTO DE QUÍMICA APLICADA, UNIVERSIDAD PÚBLICA DE NAVARRA.

Author: MUÑOZ BONILLA ALEXANDRA.
Year: 2005.
University: COMPLUTENSE DE MADRID.
Place of defense: FACULTAD DE QUÍMICAS.
Place of preparation: INSTITUTO DE CIENCIA Y TECNOLOGÍA DE POLÍMEROS (CSIC).

Summary: This memory contains doctoral thesis to study various families of block copolymers. Specifically, have synthesized new copolymers tribloque type ABA through radical polymerization controlled by atom transfer, which has changed both the chemical nature of the blocks, as in the molecular weight and composition. There has been broad structural characterization of the morphology and copolymers, and the study of their properties both in condensed phase as in solution. All this has enabled display viable applications of these new copolymers tribloque, and thus their potential as polymers funcionalizados, nanostructured systems, agents interfaciales mixtures and smart materials.

Author: KARDAK BHARAT.
Year: 2005.
University: PAÍS VASCO.
Place of defense: FACULTAD DE QUÍMICAS DE SAN SEBASTIÁN.
Place of preparation: FACULTAD DE QUÍMICA DE DONOSTIA-SAN SEBASTIAN.

Author: ÁLVARO CARRILES ELSA.
Year: 2005.
University: COMPLUTENSE DE MADRID.
Place of defense: FACULTAD DE CIENCIAS QUÍMICAS.
Place of preparation: FACULTAD DE CIENCIAS QUÍMICAS (UCM).

Summary: In this PhD thesis have addressed the synthesis of natural products through hybrid reactions involving transition metals. This would have developed two approaches through which has been generated structural diversity: Synthesis modular hybrid reaction by Nicholas and synthesis of hybrid separated by a spacer that is generated in situ process. In the first, the chemistry of cations propargílicos stabilized by clusters of dicobalto hexacarbonilo has helped prepare efficiently hybrids in which the two natural products are attached directly through links CC. Thus, it has agreed to various types of hybrids: terpeno-aromático, terpeno-heteroaromático, terpeno-terpeno, terpeno-alcaloide and even hybrid and homo heterodiméricos consisting of two subunits terpénicas and a spacer. Also, the methodology developed has helped develop hybrids of natural products desamente funcionalizados as 19-acetilgnaphalina and reserpine, and has led to a chimera esteroide-terpeno-indol. On the other hand, have been synthesized hybrid macrocíclicos through double reactions Nicholas in starting materials consisting of two subunits monoterpénicas and a spacer. It has prepared macrociclos formed by 2 terpenos and 4 atoms Co. and 4 terpenos and 8 atoms Co,. The first of these has led to dimers and trímeros steroid and monoterpenes in which the spacer is an aromatic ring or a complex with a ligand C-type ciclobutadieno or ciclopentadienona. Also, the metátesis of various derivatives diterpénicos prepared from (R )-(+)- esclareolido has led to homodímeros analogue triterpeno alfa-onoceradieno.

Author: REDONDO PALOMO M. DEL CARMEN.
Year: 2005.
University: COMPLUTENSE DE MADRID.
Place of defense: FACULTAD DE CIENCIAS QUÍMICAS.
Place of preparation: FACULTAD DE CIENCIAS QUÍMICAS.

Summary: The research included in the Doctoral Thesis has focused on two main aspects: the development of new methodologies synthetic structures polycyclic beta-lactámicas and heteroaromatic interest by potential biological reaction cicloadición [2 +2], reaction radicalaria and reaction tandem regroupement / cicloadición Diles-Alder of alfa-alenoles. Moreover, it has done the synthesis of various nitrogen products of biological interest such as pirroles funcionarizados through a process tandem of openness and ciclación intramolecular of alenos beta-lactámicos derivatives alfa-hidroxiácidos by reaction of aldehydes beta lactámicos with 2-trimetilsililtiazol and finally synthesizing indolizidinonas through a sequence of reactions involving primarily a hidroxihomologación of aldheído beta-lactámico of departure, followed by cicloadición 1,3-dipolar on iluros of azometino derivatives alfa-alcoxiacetaldehídos beta-lactámicos and alfa-aminoésteres, and finally a process of opening and regrouping in basic means of adults obtained.

Author: MARTÍNEZ CLAVIJO BEATRIZ.
Year: 2005.
University: LA RIOJA.
Place of defense: UNIVERSIDAD DE LA RIOJA.
Place of preparation: UNIVERSIDAD DE LA RIOJA.

Summary: The first objective achieved in this thesis has been acquiring experience both personal and laboratory capable of dealing with any problems that may arise in future developments in the company Metal Rubber Products SL, using the Quimiometría as an essential tool in the search for those formulations that meet specific requirements. After addressing the first study in search of heat resistant rubber based on natural rubber (NR) or synthetic (ER) were obtained formulations quite significant. Applying several designs of experiments and electing different influences, it was determined that the factorial design of 24 was the most appropriate. Even getting a model capable of predicting behavior only to a qualitatively new level, it has been used by the company for particular cases of new developments. In other words, it was noted the influence of two kinds of rubber and sulfur and accelerators, as the main factors which affect the heat resistance. In the second study were sought jointly gums resistant to fatigue and heat, based either in natural rubber (NR) or mixtures of natural and polybutadiene rubber (NR / BR). The study was divided in turn into two parts, differentiated by the type of acceleration used, (FAT designated as gums, with a high level of sulfur and as a FAC, low sulfur). By applying in this case the multiple linear regression model interactions with the results obtained with formulations performed, obtaining enough predictive models and a set of equations for each property, which will serve us in the future to be able to know in advance what formulation the laboratory will be needed in order to obtain a value of the property sought by the company, taking into account customer requirements. In an effort to optimize all the results obtained in the preceding paragraphs (FAT and formulations FAC), and in order to get to meet all the requirements requested by our clients, were used functions can be optimized for desirability three or more properties once, as were the breaking load, elongation at rupture, Desgarro and Permanent September. We designed, in addition, a user-friendly software, which allows the calculation of such functions for different properties, if in the future the company interested in taking other properties of departure. Finally, a case study is presented to reveal the actual use of the functions of desirability, and power closer to a future in which more valuable to the company. If you have clear goals to achieve, that is what values a certain properties you need, using the contours for all possibilities, and only superponiéndolas, we will know the best to consider or to put it another way, what variables being involved in the area of optimal said.

Author: Ardá Freire Ana.
Year: 2005.
University: A CORUÑA.
Place of defense: Facultade de Ciencias.
Place of preparation: Facultad de Ciencias.

Summary: This thesis describes the synthesis of different structures enantioméricamente pure? -metil Aminoacídicas as models for the implementation of structural analysis configuracional based on coupling constants (NMR) in order to study its applicability to the determination of their relative configurations. The ultimate goal is the application of this analysis to the determination of estereoquímica the new compound dipeptídico polychlorinated Dysitiazolamida, isolated in our group's research espnja Dysidea sp. The synthesis of these structures was carried out through different synthetic strategies: Alquilación electrófila of acid derivatives L-glutámico and aÂ'cido L-piroglutámico. The latter allows the introduction of the methyl group at the position? So diasteroespecífica from exometileno (2S) -N- (terc-butoxicarbonil) -4-metilenpiroglutamato of terc-butilo by catalytic reduction. However, the introduction by 1,3-inducción asymmetric's dianión of acid derivative L-glutámico leads to improved yields. Through these two strategies were synthesized (2S, 4S) -2 - (terc-butoxicarbonil) amino-5-bromo-4-metilpentanoato of terc-butilo and (2S, 4S) -2-[bis (terc-butoxicarbonil) amino] -5.5 - dicloro-4-metilpentanoato of terc-butilo in the latter group gem-dicloruro was introduced from an aldehyde which was transformed into a hidrazona, which is made to react with CuCl2 and trietilamina. The intonation electrófila derivatives derivatives carboximidas chiral, which allowed the obtaining of (2S, 4R) -2-[bis (terc-butoxicarbonil) amino] -5.5 -dicloro-4-metipentanoato of terc-butilo Analysis configuracional applied addition to these compounds applied to the structures: (2S, 4R) and (2S, 4R) -2-[bix (terc-butoxicarbonil) amino] -5 - (terc-butildifenilsililoxi) -4 metilpentanoato of terc-butilo (2S, 4S) - N, N-bis (terc-butoxicarbonil) -4-metilglutamato Dimethyl, and (2S, 4R) -4 - (N-terc-butoxicarbonil-N-metilamino) -1-terc-butoximetil -2-methyl-4 (tiazol-2-il) butane, and two different ways: Based on the coupling constants and experimental identified through espetros NMR: 1 H PECOSY, HETLOC, ps-HMBC and J-HMBC, mainly. Based on the comparison of experimental constants with the theoretical obtained from the minimization using geometric theory of functional density (DFT) and subsequent theoretical calculation also using DFT. Finally it was determined the configuration relative Dysitiazolamida through constant coupling homonucleares, heteronucleares and NOE correlations, and it was proposed as the absolute (2S, 4S, 6S, 8S) Finally attempted to corroborate this configuration by total synthesis for what which were synthesized compounds (2S, 4S) -1 - (N-terc-butoxicarbonil-N-metilamino) -4.4 -dicloro-3-metil-1- (tiazol-2-il) butane, and (2S, 4 S) -5.5 -dicloro-4-metil-2-propionilamino-pentaoato methyl.

Author: ALONSO HERNANDEZ DULCE Ma..
Year: 2005.
University: SALAMANCA.
Place of defense: DEPARTAMENTO QUIMICA FARMACEUTICA.
Place of preparation: FACULTAD DE FARMACIA.

Summary: The work described in the Doctoral Thesis is aimed at preparing new trialquilsiloxi-1 ,3-butadienos, to study its reactivity in reactions Diels-Alder and its application in the synthesis of new compounds with potential biological activity. In previous work of the research group had described the synthesis of analogs open alkaloids indolocarbazólicos, alkaloid Arciriaflavina Woe to similar alkaloid that is not symmetrical.

Author: MATEO MATEOS CARMEN.
Year: 2005.
University: SALAMANCA.
Place of defense: UNIVERSIDAD DE SALAMANCA.
Place of preparation: DEPARTAMENTO QUIMICA FARMACEUTICA.

Summary: The main objective of this work is the synthesis and testing of new chemotherapeutic agents and studying their interaction with protein called tubulin. The combretastatina is a small molecule found in the bark of an African shrub, Combretatum Caffrum. Produces inhibition of tubulin polymerization, exerts its effect antimitótico through the despolimerización of microtubules and stops the cell cycle in cancer cells. The combretastatina A-4 is the most powerful compound and the reference in this investigation. A new family of estilbenofamos polioxigenados have been synthesized as analogues combretastatinas antimitóticas conformacionalmente restricted. We extracted compounds derived from diethylene glycol and 1,6-hexanodiol through the process of olefinación of McMurry, while the catalysis of Grubbs ruled in the proceeding metátesis locking ring with such products macrocíclicos. The intermediate compounds are synthesized by the reaction of Mitsunobu with high yields. The study of the structure of these compounds was just through methods espectrocópicos (NMR, Espectrometrías mass, HPLC, fluorescence, â |) Once these compounds were prepared, tried for their activity antimitótica, test whether the structure activity relationship among these compounds and combretastatina A-4 is also reflected in their biological properties. The study of the effect of its particular shape and biological activity are very interesting in the search for new bioactive compounds. There is a decrease in activity antimitótica, which could be attributed to the restriction imposed on the rings fenílicos by the bridge.

Author: SILVA LÓPEZ CARLOS.
Year: 2005.
University: VIGO.
Place of defense: FACULTAD DE QUÍMICA.
Place of preparation: UNIVERSIDAD DE VIGO.

Summary: There has been a theoretical study on the electronic structure and reactivity of two structural reasons ubícuos in metabolic processes vital to living organisms, polinenales and vinil-alenos. In a first approximation mainly theoretical, but in relevant cases has been implemented, has done an exhaustive study of the process pseudo (pericíclicos) can be more important than go into these compounds. It has been described processes electrociclación, transposition sigmatrópica, adding quelotrópica and cicloisomerización. This section has paid special attention to the processes of isomerization thermal 11-cis-retinal. This important polienal undergoes a process of fotoisomerización delicately estereocontrolado by the receiver (rodopsina). In the absence of protein and thermal conditions, however, this molecule undergoes at least two competitive isomerization processes that lead to todo-trans-retinal and 13-cis-retinal respectively. It has been proven experimentally that the isomerization mechanism must be different and independently for each of the two products. We know what the process isomerization 11-cis-retinal to todo-trans-retinal, but has never described the process leading to 13-cis-retinal. We have studied computationally alternatives mecanísticas compatible with the product and found it has been concluded that the most likely candidate mechanistic comprises an intricate path of reaction that begins with a double prototropía followed by a closing and opening electrocíclica with preserving the direction of rotation in these two last processes. This proposal has since been proven experimentally using isotopic substitution. Moreover, it has assisted in the design of ligands polienal of bacteriorodopsina with optical properties modulated through a theoretical study of the electronic excitation frequencies through a systematic exploration of the most current methodological tools available. Finally, it has described the mechanism ciclación catalysed by Lewis acids of heptatrienoatos, synthetic precursors (-) -crispateno. It has been found that the process of double ciclación suffering the precursor is completely decoupled. The mechanisms could interreptar as a ciclación type Nazarov of a cation pentadienilo leading to a system that is cation cyclopentenyl captured intramolecularmente through a mechanism without barrier for a replacement enol to lead the skeleton bicíclico present in the natural product. The key to this mechanism is that the evolution of cation cyclopentenyl occurs through a process without activation barrier, which allows an unusual esterocontrol along the reaction coordinate.

Author: ALONSO GÓMEZ JOSÉ LORENZO.
Year: 2005.
University: VIGO.
Place of preparation: FACULTAD DE QUÍMICAS.

Author: GARCÍA APARICIO CARLOS.
Year: 2005.
University: COMPLUTENSE DE MADRID.
Place of defense: FACULTAD DE FARMACIA.
Place of preparation: FACULTAD DE FARMACIA.

Summary: The thesis deals with two innovative approaches in the field of Química-Médica, such as the study of a new method of inhibiting the transcriptasas reverse (Tl) of human immunodeficiency virus type 1 (HIV-1), including interference in the process dimerización of the enzyme, and the development of a new approach pro-fármaco. This has been used as a common tool to derivatives TSAO, a family unique inhbidores specific HIV-1, developed in our working group. Derivatives TSAO is the first and so far the only example of a molecule not peptísica able to interfere with the process of dimerización of the enzyme, interaciconando in handles Beta7-beta8 of subunit p51 of Tl. The first part of the thesis is aimed at the design, synthesis and biological evaluation of short peptides mimicking interactions of a key part of the sequence handles beta7-beta8 of enzina where interact derivatives TSAO. The synthesis of these inhibitors are attempts to explore the process dimerización as a new alternative mechanism of inhibition of the enzyme, which could lead to new families of potent inhibitors and perhaps less likely to develop resistance. Similarly, a study addresses structural and conformacional using NMR techniques that handles beta7-beta8, which can provide useful information in the design of new potential inhibitors of the above process dimerización. In the second part of the thesis deals with a new approach pro-fármaco consisting of the union of sequences differ and tetrapeptídicas, very specific drug that unfavorable pharmacological profiles. These sequences are specifically recognized by the enzyme endogenous dippeptidil-peptidasa IV (DPP IV or CD26), leading to the release of the drug. This approach has been applied to antiviral compounds, anticancersoso and fluorescent substrates or cromogénicos structure, nature and properties fisicoquímias very different.

Author: FERNÁNDEZ BLÁZQUEZ JUAN PEDRO.
Year: 2005.
University: COMPLUTENSE DE MADRID.
Place of defense: FACULTAD DE CIENCIAS QUÍMICAS.
Place of preparation: FACULTAD DE CIENCIAS QUÍMICAS.

Summary: This thesis shows the synthesis of polymer liquid crystals either as main chain of side chain. In both cases, using the group biphenyl as mesógeno united through espaciodores metilénicos odd. We carried out the structural elucidation of these polymer by NMR and its molecular weight by GPC. Its thermal transitions were studied by various techniques such as DSC, both conventional and modulated by X-ray equivos conventional as well as synchrotron radiation experiments that were conducted at the synchrotron in Hamburg (Hasylab). In a final chapter shows the mechanical properties of the polymer main chain, in the various stages that may present. As a study of the orientation of the stages esmércticas experiments traction uniazial when the temperature varies, and the speed of that experiment.