Synthetic studies directed toward the total synthesis of azadirachtin. Development of a computer program facilitating mass spectrometry structure elucidation
Abstract
In the first part of this work, the results of research on a general approach to the total synthesis of Azadirachtin is described. The original pathway uses a Nishiyama-Stork radical cyclization as a key step to obtain the C$\sb4$ quaternary center of Azadirachtin. This strategy allows late functionalization of the B ring. This initial approach met some success, and lead to the investigation of different domains to improve the current methodology: (1) new cyclization reagents, (2) attempts to synthesize new radical propagators without a hydrogen source, (3) different modifications of the substrate. The second part of the dissertation deals with a new computer program named MASStry 2.0 that is designed to facilitate mass spectrometry structure elucidation. Running on Macintosh computer family, this user-friendly program is able to aid to the identification of an unknown from mass spectrometry. It is also able to perform: (1) isotope pattern calculations, (2) interpretation of complex structures to deliver the molecular formula, (3) incorporation of deuteriums and labeled elements, (4) elemental analysis calculation, (5) identification of fragments from parent compounds.
Degree
Ph.D.
Advisors
Fuchs, Purdue University.
Subject Area
Organic chemistry
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