Isolation, structure elucidation and analytical methodologies for natural products

Abstract

Several chemically diverse natural products were isolated from cyanobacterial media and cell mass from both marine and terrestrial sources. The media investigations led to the discovery of six new stereochemically rich sesquiterpenoids from two structural classes. Their full characterization was a challenging effort that led to development of a comprehensive approach to the structure elucidation of each class of compound utilizing common spectroscopic analyses heavily supported with computational NMR and ECD prediction. A series of studies involving the cyanobacterial consortium HT-58-2 were conducted. The first study has assessed tolyporphin production in various growth conditions and searched for tolyporphin production in other cyanobacterial strains. The second, a cell mass extraction, led to two new tolypodiol analogs and the final project, a time-course study, used molecular networking to provide insights into secondary metabolite production over time and identify potential targets for future natural product projects. Two other cell mass extraction projects of Moorea producens 11-Kauai-92 and Calothrix sp. R-3-1, led to the isolation and partial characterization of a potentially new malyngamide and a new glycoside, respectively. Finally, a series of projects focused on analytical method development and data analysis are presented starting with a targeted method development for LCMS analysis of carotenoids, followed by a second method development utilizing an LCMS Omics approach and its data analysis, and a final section with a series of projects highlighting the integral nature of computational prediction on the interpretation of ECD spectra.