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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Understanding the Role of Energy in Chemical Reactions from Mechanics to Photochemistry

McKissic, Kelley S. 16 October 2015 (has links)
No description available.
32

Chemistry of Acyl Nitrenes in the Synthesis of Carbamates and Complex Heterocycles

Afeke, Cephas Ofoe 16 September 2015 (has links)
No description available.
33

Computational Studies of Anti-Tumor Drug Tirapazamine and Reactions and Rearrangements of nitrenes and Carbenes

Liu, Jin 24 August 2005 (has links)
No description available.
34

Computational and Experimental Studies of Excited States of Different Precursors of Carbenes and Nitrenes

Luk, Hoi Ling 16 August 2012 (has links)
No description available.
35

Studies on Chemo- and Site-Selective C-H Amination of Aniline and Phenol Derivatives with Dirhodium Catalysts and Catalytic Asymmetric Synthesis of Inherently Chiral Calixarenes / ロジウム二核錯体によるアニリン及びフェノール誘導体の位置及び化学選択的C-Hアミノ化並びに分子不斉カリックスアレーンの触媒的不斉合成に関する研究

Chen, Gong 23 March 2021 (has links)
京都大学 / 新制・課程博士 / 博士(薬科学) / 甲第23138号 / 薬科博第137号 / 新制||薬科||15(附属図書館) / 京都大学大学院薬学研究科薬科学専攻 / (主査)教授 川端 猛夫, 教授 高須 清誠, 教授 大野 浩章 / 学位規則第4条第1項該当 / Doctor of Pharmaceutical Sciences / Kyoto University / DFAM
36

Development of chemical strategies to prepare multifunctional carbon nanotubes for anticancer therapy / Développement de stratégies chimiques pour préparer des nanotubes multifonctionnels pour la thérapie anticancéreuse

Spinato, Cinzia 28 September 2015 (has links)
L’application de nanotubes de carbone (CNTs) dans le domaine biomédical a été largement explorée grâce à leur propriétés physico-chimiques et à leur biocompatibilité. Par la fonctionnalisation extérieur et/ou intérieur des CNTs c’est possible de préparer des nouveaux conjugués avec différentes propriétés et applications. On a exploré la modification des nanotubes par voie covalente pour leur utilisation comme vecteurs de biomolécules pour achever la thérapie anticancéreuse. Pendant ma thèse, j’ai travaillé sur trois projets: l’application de différentes approches pour la conversion des groupes acides carboxyliques de MWCNTs oxydés en amines, dans le but de préparer des conjugués capables de complexer du siRNA (petits ARN interférents). Dans un second projet, j’ai développé des conjugués à base de nanotubes de carbone couplés avec un fragment d’anticorps thérapeutique via une liaison clivable afin d’en étudier le potentiel antitumoral. Dans le dernier projet, on a achevé la fonctionnalisation de CNTs remplis avec des molécules radioactivables par cycloaddition de nitrene et ensuite conjugué un anticorps de ciblage tumoral. Le but été d’utiliser les nanotubes comme vecteurs pour la délivrance de radioactivité à l'intérieur des cellules tumorales ciblées par l’anticorps. On a aussi conduit des investigations biologique, afin d’évaluer la toxicité et l’efficace de ce conjugué. / The application of carbon nanotubes (CNTs) in the biomedical field has been widely explored thanks to their physico-chemical properties and their biocompatibility. By the external and/or internal functionalization of CNTs it is possible to prepare novel conjugates tailoring different properties and applications. We have investigated the covalent derivatization of CNTs by different chemical strategies to achieve suitable carriers for anticancer therapy. In one project, we have explored the conversion of the carboxylic groups of oxidized CNTs into amino groups, and the ability of these conjugates to complex genetic material, for gene delivery. In another project, CNTs have been functionalized with linkers bearing a cleavable disulfide bond, and further conjugated to a therapeutic nanobody for controlled intracellular drug release. Finally, we have investigated the reactivity of close-ended CNTs filled with radioactivable material toward Bingel and nitrene cycloadditions and the conjugation of a targeting antibody, for the target delivery of radioactivity. By several characterization techniques we have proved that the antibody is covalently grafted to the CNT-carrier and it still possesses its targeting ability. Investigations on the biological profile of these conjugates (cytotoxicity, targeting, uptake, biodistribution) have been also carried out.
37

The Design and Synthesis of Functionalized Porphyrins and Their Applications in Group Transfer Reactions, Medicine, and Materials

Fields, Kimberly Bliss 20 October 2010 (has links)
Porphyrins and their analogs are a class of chemically and biologically important compounds that have found a variety of applications in different fields such as catalysis, medicine, and materials. The physical, chemical, and biological dependence of the peripheral substituents of porphyrins on their properties has prompted great effort towards the synthesis of new porphyrins with different electronic, steric, and conformational environments. To this end, porphyrins have been prepared using a modular approach from bromo- and triflate synthons. These synthons underwent palladium-catalyzed cross-coupling with chiral amines, amides, alcohols, and boronic esters to create products that were tested for biological activity. Metalloporphyrins were screened as catalysts for cyclopropanation and C-H amination, yielding excellent results. By changing the porphyrin catalysts’ chiral groups, all four enantiomers could be produced in the cyclopropanation of styrene derivatives with ethyl diazoacetate (or t-butyl diazoacetate). Similarly, a variety of sultams were produced from benzenesulfonyl azides in high yields and high enantioselectivities using chiral cobalt porphyrins as catalysts. Porphyrins, metalloporphyrins, and the catalytic products generated were tested for activity in a variety of medicinal collaborations, namely as therapeutics for methicillin-resistant Staphylococcus aureus, Alzheimer’s disease, malaria, viral infections that include influenza and herpes, and cancer, as well as biological studies with ferrochelatase. They were also used in materials experiments with two different polymer groups.
38

Development of 3d Transition Metal Complexes of Hydrotris(pyrazolyl)borates (Tp) asRedox Catalysts

Aboelenen, Ahmed January 2019 (has links)
No description available.
39

Characterizing triplet azo biradical and corannulene- halogen complexes by laser flash photolysis

Li, Qian January 2012 (has links)
No description available.
40

Sultam Synthesis Via Intramolecular C-H Amination of Hydroxylamines

Quartus, Jasper Adam May 22 November 2021 (has links)
Nitrogen is a vital element for the existence of life, as shown by its frequent presence in essential biomolecules, and inclusion into valuable drugs. Sulfonamides and their heterocycle counterpart, sultams, are N-containing functional groups and metabolically stable amide isosteres. Sulfa drugs, which contain these moieties, have a broad spectrum of medical applications. The industrial value of sultams has prompted the development of novel methods for their synthesis, and metal-catalyzed C-H amination reactions with nitrene precursors have recently shown promise. The current thesis presents a survey of conditions for benzo[d]sultam synthesis via intramolecular C-H amination of N-acyloxysulfonamides. Initially, using Ru(Bpy)3(PF6)2 as a photocatalyst and Et3N as a base enabled benzo[d]sultam formation by tertiary C-H amidation. The photoredox conditions were optimized to accommodate other 2,6-disubstituted-N-acyloxysulfonamides upon omission of the base, which consistently gave sulfonamide byproducts. Control reactions indicated that a thermal base-induced reaction was simultaneously occurring, both enabling productive C-H amidation and byproduct formation. Systematic optimization of base-induced conditions enabled sultam synthesis from 2,6-dialkyl- and tertiary ortho-monoalkyl-precursors in moderate yield, but sulfonamide formation still impeded the reaction.   An additional control reaction indicated that a thermal Ruthenium-catalyzed C-H amidation reaction was possible. Indeed, heating N-acyloxysulfonamides in the presence of Ru(Bpy)3(PF6)2 and in the absence of light and base enabled efficient C-H amidation, particularly with DCE as a solvent. A representative scope of 12 benzo[d]sultams was then synthesized including entries derived from ortho-monoalkyl-N-acyloxyarylsulfonamides. Aside from optimizing an efficient reaction for the synthesis of benzo[d]sultams through the cyclization of N-acyloxyarylsulfonamides, including the challenging primary C-H amidation of orthomonomethyl-substrates, the unique reaction conditions developed in this thesis set precedent for future investigation of hydroxylamine derived nitrene precursors. The optimization and design of superior ruthenium catalysts could allow for more challenging C-H amination reactions with hydroxysulfonamide derivatives and similar N-oxy nitrene precursors.

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