Sökning: "Alkaloids"
Visar resultat 21 - 25 av 36 avhandlingar innehållade ordet Alkaloids.
21. Bispidine Derivatives : Synthesis and Interactions with Lewis Acids
Sammanfattning : In this thesis, the improved synthesis and investigations into the properties of some 3,7-diazabicyclo[3.3.1]nonane (bispidine) derivatives are described. LÄS MER
22. Stereoselective Nucleophilic Additions to α-Amino Aldehydes: Application to Natural Product Synthesis
Sammanfattning : This thesis deals with the development and application of new synthetic methodology for stereo- or regioselective construction of carbon-carbon bonds in organic synthesis. The first part of this thesis describes the development of a divergent protocol for stereoselective synthesis of chiral aminodiols by employing Mukaiyama aldol additions to syn- and anti-α-amino-β-silyloxy aldehydes. LÄS MER
23. New Arylation Strategies Based on Organomain Group Reactivity
Sammanfattning : The work in this thesis describes the development of new heteroarylation methodology based on transition metal-catalysed C-H functionalisation and the properties of organomain group compounds. The underlying reaction mechanisms and reactivity patterns of the (hetero)arene substrates are also investigated. LÄS MER
24. Syntheses of some tri- and tetracyclic heterocycles containing an indole moiety
Sammanfattning : This thesis deals with the development of new synthetic methods leading to fused tri- and tetracyclic heterocycles, many of which have interesting biological activity such as antiviral and DNA intercalating properties. The reactions between isatins and 2-aminobenzylamine in acetic acid can give, depending on the conditions, either complex spirooxindoles or indolo[3,2-c]quinolin-6-ones. LÄS MER
25. Novel clean-up, concentration and laser desorption/ionization strategies for mass spectrometry
Sammanfattning : Despite valuable advantages of mass spectrometry (MS) techniques they still have drawbacks that need to be overcome, notably their sensitivity to various kinds of interfering substances and associated difficulties involved in detecting signals from analytes present in trace quantities. Thus, high quality analytical data could be acquired by improving sample pre-treatment techniques and/or ionization methods to increase ionization yields and/or avoid the generation of unwanted ions. LÄS MER