Les travaux de cette thèse ont permis de développer de nouvelles réactions de post-condensations associées à la réaction de Ugi dans le domaine de la chimie radicalaire. Dans la littérature, ces post-condensations concernent essentiellement la chimie ionique ou organométallique. Divers types de chimie radicalaire ont été utilisés sans employer de métaux lourds toxiques tels que les dérivés stannylés. Dans un premier temps, nous avons réussi à associer des réactions de cyclisations radicalaires à la réaction de Ugi à partir de xanthates. Nous avons également mis au point un processus de cyclisation radicalaire de xanthates sur des alcynes. Ensuite, nous avons développé une méthodologie d'addition radicalaire-cyclisation sur des hydrazones à partir de substrats de Ugi. Enfin, nous avons réalisé des réactions de cascades radicalaires, additions et cyclisations, à partir d'acétate de Manganèse. Cela a conduit à la formation de molécules complexes via des mécanismes originaux (composés spirocycliques, cyclopropanes migration d'aryle, cyclisations en position ipso, etc.) en une seule étape après la réaction de Ugi.

Pyrazoles have been studied for over a century as an important class of heterocyclic compounds and continue to attract considerable interest due to the broad range of biological activities they possess. The electrophilic cyclization of the acetylenic hydrazones initiated by molecular iodine could provide new ways of synthesizing biologically active 4-iodopyrazole derivatives, which are important precursors for the synthesis of highly substituted pyrazole derivatives. For this reason, we investigated the synthesis of 4-iodopyrazole derivatives, such as 1-aryl- 5-alkyl/aryl-4-iodopyrazoles, starting from phenylhydrazine and ,-acetylenic aldehyde derivatives. Initially, ,-acetylenic aldehydes were synthesized by formylation reaction of corresponding alkynes with DMF. Then, hydrazone derivatives of these aldehydes were prepared by heating them with phenylhydrazine in a neat manner at 55 &deg / C for 5 h. Finally, acetylenic phenyl hydrazone derivatives were subjected to electrophilic cyclization by treating with excess molecular iodine at 80 &deg / C for 3 h. Although electrophilic cyclization is commonly used in organic chemistry, it has not been employed for the cyclization of acetylenic phenyl hydrazones to pyrazole derivatives. Under optimized conditions, these reactions afforded 1-aryl-5-alkyl/aryl-4-iodopyrazole derivatives in moderate to good yields as the single or the major product of the reactions. In some cases, 1-aryl-5-alkyl/arylpyrazole derivatives resulted from these reactions as minor products. In conclusion, 4-iodopyrazole derivatives were synthesized for the first time directly from acyclic starting materials, ,-acetylenic phenylhydrazones and iodine, via electrophilic cyclization.

Gegenstand der vorliegenden Arbeit ist die intensive strukturelle Untersuchung von Arylhydrazonen des Pentan-2,4-dion-Typs. Durch Variation des Molekülgerüstes und der Synthese geeigneter Arylhydrazonderivate sowie der anschließenden strukturellen Charakterisierung mittels Röntgen-Einkristallstrukturuntersuchung sollte versucht werden, die Molekülgeometrien sowie packungsbestimmende Parameter zu ermitteln. Dies dient längerfristig der Erschließung dieser Substanzklasse im Sinne des Crystal Engineering zum Aufbau supramolekularer Netzwerkstrukturen und zur Klärung festkörperbedingter Phänomene. Es lässt sich feststellen, dass die untersuchten Arylhydrazone über ein sehr dominantes, intramolekulares, sechsgliedriges Wasserstoffbrückenbindungsmotiv verfügen, welches anhand von 28 Röntgeneinkristallstrukturanalysen von Arylmono- und Dihydrazonen, Hydrazonkomplexen sowie strategisch relevanten Schlüsselverbindungen im Hinblick auf strukturdominierende Parameter untersucht werden konnte. Neben der Analyse der erhaltenen Festkörperstrukturen und dem Vergleich mit berechneten Geometrien, spielte dabei die eingehende Untersuchung unerwarteter Substitutions- und Komplexierungsreaktionen sowie konformell- und tautomer- geprägter Eigenheiten eine wesentliche Rolle, die die Arylhydrazone in Übereinstimmung mit vorangegangenen Betrachtungen als vielgestaltige Substanzklasse bestätigen konnten.

Techn. Hochsch., Diss., 2001--Aachen.

Techn. Universiẗat, Diss., 2003--Darmstadt.

abstract: ABSTRACT Manipulation of biological targets using synthetic or naturally occurring organic compounds has been the focal point of medicinal chemistry. The work described herein centers on the synthesis of organic small molecules that are targeted either to cell surface receptors, to the ribosomal catalytic center or to human immunodeficiency virus reverse transcriptase. Bleomycins (BLMs) are a family of naturally occurring glycopeptidic antitumor agents with an inherent selectivity towards cancer cells. DeglycoBLM, which lacks the sugar moiety of bleomycin, has much lower cytotoxicity in cellular assays. A recent study using microbbuble conjugates of BLM and deglycoBLM showed that BLM was able to selectively bind to breast cancer cells, whereas the deglyco analogue was unable to target either the cancer or normal cells. This prompted us to further investigate the role of the carbohydrate moiety in bleomycin. Fluorescent conjugates of BLM, deglycoBLM and the BLM carbohydrate were studied for their ability to target cancer cells. Work presented here describes the synthesis of the fluorescent carbohydrate conjugate. Cell culture assays showed that the sugar moiety was able to selectively target various cancer cells. A second conjugate was prepared to study the importance of the C-3 carbamoyl group present on the mannose residue of the carbohydrate. Three additional fluorescent probes were prepared to improve the uptake of this carbohydrate moiety into cancer cells. Encouraged by the results from the fluorescence experiments, the sugar moiety was conjugated to a cytotoxic molecule to selectively deliver this drug into cancer cells. The nonsense codon suppression technique has enabled researchers to site specifically incorporate noncanonical amino acids into proteins. The amino acids successfully incorporated this way are mostly α-L-amino acids. The non-α-L-amino acids are not utilized as substrates by ribosome catalytic center. Hoping that mutations near the ribosome peptidyltransferase site might alleviate its bias towards α-L-amino acids, a library of modified ribosomes was generated. Analogues of the naturally occurring antibiotic puromycin were used to select promising candidates that would allow incorporation of non-α-L-amino acids into proteins. Syntheses of three different puromycin analogues are described here. The reverse transcriptase enzyme from HIV-1 (HIV-1 RT) has been a popular target of HIV therapeutic agents due to its crucial role in viral replication. The 4-chlorophenyl hydrazone of mesoxalic acid (CPHM) was identified in a screen designed to find inhibitors of strand transfer reactions catalyzed by HIV-1 RT. Our collaborators designed several analogues of CPHM with different substituents on the aromatic ring using molecular docking simulations. Work presented here describes the synthesis of eight different analogues of CPHM. / Dissertation/Thesis / Ph.D. Chemistry 2013

Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-07-13T20:07:47Z No. of bitstreams: 1 patriciaramosgomes.pdf: 2798907 bytes, checksum: 7ef017bb527cb14c4d8c3f85fab63686 (MD5) / Approved for entry into archive by Diamantino Mayra (mayra.diamantino@ufjf.edu.br) on 2016-07-14T10:38:54Z (GMT) No. of bitstreams: 1 patriciaramosgomes.pdf: 2798907 bytes, checksum: 7ef017bb527cb14c4d8c3f85fab63686 (MD5) / Made available in DSpace on 2016-07-14T10:38:54Z (GMT). No. of bitstreams: 1 patriciaramosgomes.pdf: 2798907 bytes, checksum: 7ef017bb527cb14c4d8c3f85fab63686 (MD5) Previous issue date: 2011-04-29 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Diversos análogos de curcumina monocarbonilados são descritos na literatura, apresentando inúmeras e pronunciadas atividades biológicas, a saber: atividades antitumoral, antioxidante, anti-inflamatória, antiangiogênese, entre outros. A partir destes análogos obtêm-se compostos contendo a funcionalidade hidrazona, que apresentam também uma variedade de atividades biológicas, tais como: antiinflamatória, antitumoral, analgésica, dentre outros. Com o objetivo de desenvolver novas moléculas que possam atuar como agentes antioxidante, antitumoral, antiinflamatório, antituberculose, antimalária e esquistossomicida, este trabalho visou à síntese e caracterização de análogos de curcumina monocarbonilados e suas respectivas fenilhidrazonas contendo em suas estruturas grupos doadores e retiradores de elétrons, além de cadeias alifáticas alquiladas de 8, 9, 10 e 12 carbonos na posição para dos anéis aromáticos para posterior avaliação biológica dos mesmos. Foram obtidos treze análogos de curcumina monocarbonilados via reações de condensação aldólica em meios básico e ácido utilizando como reagentes a acetona e diferentes aldeídos aromáticos, heteroaromáticos e alquilados. Para a obtenção dos análogos de curcumina alquilados utilizou-se como material de partida o p-hidroxibenzaldeído, o qual foi submetido à reação de alquilação usando os haletos de alquila comerciais 1-clorooctano, 1-bromononano, 1-clorodecano e 1-clorododecano como agentes alquilantes. Foram obtidas quinze fenilhidrazonas a partir dos derivados de curcumina previamente preparadas por meio de reações de adição nucleofílica em meio ácido utilizando como reagentes a 2,4-dinitrofenilhidrazina e a 4-nitrofenilhidrazina. As estruturas dos produtos obtidos foram elucidadas pelos seus espectros no infravermelho, UV-visível, RMN de 1H e de 13C. Alguns análogos de curcumina e fenilhidrazonas foram submetidos a testes de atividades antioxidante, antitumoral, antibacteriana, anti-inflamatória, antimalária e esquistossomicida. / Several mono-carbonyl curcumin analogues are described in the literature, presenting numerous and pronounced biological activities, namely: antitumor, antioxidant, anti-inflammatory, anti-angiogenesis, among others. From these analogues are derived compounds containing the functionality hydrazone, which also present a variety of biological activities such as: anti-inflammatory, antitumor, analgesic, among others. In order to develop new molecules that can act as antioxidant, anticancer, anti-inflammatory, antitubercular, antimalarial and schistosomicidal agents, this work aimed at the synthesis and characterization of mono-carbonyl curcumin analogues and their phenylhydrazones containing in their structures donor groups, withdrawing electron and alkylated aliphatic chains of 8, 9, 10 and 12 carbons in the para position of the aromatic rings for further biological evaluation of them. We obtained thirteen mono-carbonyl curcumin analogues by aldol condensation reactions in basic and acidic media using acetone as reagents and different aromatic aldehydes, alkyl and heteroaromatic. To obtain of the alkylated curcumin analogues, were used as the starting material p-hydroxybenzaldehyde, which was submitted to the alkylation reaction using alkyl halides 1-chlorooctane, 1-bromononane, 1-chlorodecane and 1-chlorododecane as alkylating agents. We obtained from fifteen phenylhydrazones curcumin derivatives previously prepared by nucleophilic addition reactions in acidic media using reagents such as 2,4- dinitrophenylhydrazine and 4-nitrophenylhydrazine. The structures of the products obtained were elucidated by their infrared, UV-visible, 1H and 13C NMR spectra. Some analogues of curcumin and phenylhydrazones were submitted to antioxidant, anticancer, antibacterial, anti-inflammatory, antimalarial and schistosomicidal assays.

Gegenstand der vorliegenden Arbeit ist die intensive strukturelle Untersuchung von Arylhydrazonen des Pentan-2,4-dion-Typs. Durch Variation des Molekülgerüstes und der Synthese geeigneter Arylhydrazonderivate sowie der anschließenden strukturellen Charakterisierung mittels Röntgen-Einkristallstrukturuntersuchung sollte versucht werden, die Molekülgeometrien sowie packungsbestimmende Parameter zu ermitteln. Dies dient längerfristig der Erschließung dieser Substanzklasse im Sinne des Crystal Engineering zum Aufbau supramolekularer Netzwerkstrukturen und zur Klärung festkörperbedingter Phänomene. Es lässt sich feststellen, dass die untersuchten Arylhydrazone über ein sehr dominantes, intramolekulares, sechsgliedriges Wasserstoffbrückenbindungsmotiv verfügen, welches anhand von 28 Röntgeneinkristallstrukturanalysen von Arylmono- und Dihydrazonen, Hydrazonkomplexen sowie strategisch relevanten Schlüsselverbindungen im Hinblick auf strukturdominierende Parameter untersucht werden konnte. Neben der Analyse der erhaltenen Festkörperstrukturen und dem Vergleich mit berechneten Geometrien, spielte dabei die eingehende Untersuchung unerwarteter Substitutions- und Komplexierungsreaktionen sowie konformell- und tautomer- geprägter Eigenheiten eine wesentliche Rolle, die die Arylhydrazone in Übereinstimmung mit vorangegangenen Betrachtungen als vielgestaltige Substanzklasse bestätigen konnten.

Le motif spiroacétal est une structure présente dans le squelette de nombreuses molécules naturelles possédant des activités biologiques variées et pour laquelle il existe de nombreuses voies de synthèse. En revanche, son analogue azoté, le motif spiroaminal a été beaucoup moins étudié. Le premier de nos objectifs a consisté à développer une voie de synthèse énantiosélective, la plus générale possible, de ce motif. La stratégie retenue repose sur une étape clé de spirocyclisation acido-catalysée d'aminohydroxycétones issues de l'alkylation séquentielle de l'acétone N,N-diméthylhydrazone par divers synthons iodés. Si les spiroaminals attendus n'ont pas pu être obtenus, ces cétones polyfonctionnalisées ont permis d'accéder efficacement à des spiroacétals originaux : les 1,6-dioxaspiro [4.6] undécanes et les 1,7-dioxaspiro [5.6] dodécanes. Dans une deuxième partie de notre travail, nous nous sommes intéressés à la synthèse totale de la broussonétine H, spiroacétal naturel possédant une très forte activité inhibitrice vis-à-vis de β-glycosidases. Son élaboration a été envisagée par couplage entre deux fragments clé : le 2-éthynyl-1,7-dioxaspiro [5.5] undécane et un iminocyclitol porteur d'un époxyde. La synthèse de ces deux composés a été réalisée en peu d'étapes et avec d'excellents rendements. Leur couplage a permis l'obtention d'un précurseur directe de la broussonétine H. L'étape finale de déprotection reste à optimiser afin de permettre l'isolement du produit naturel.

No description available.