An approach toward the total synthesis of cylindrospermopsin

Cylindrospermopsin (1) is a naturally occurring marine alkaloid that has been of great biological and synthetic interest over the past decade. The structure of 1 contains a tricyclic guanidinium core that is linked to a uracil ring by a hydroxymethyl bridge. The six stereocenters embedded within its backbone and its high degree of functionality within a compact area renders cylindrospermopsin a challenging synthetic target. This thesis describes efforts directed toward a total synthesis of 1. In the key step of our approach, the urea moeity of substrate 2 undergoes a base-mediated intramolecular conjugate addition onto the alkynyl pyrimidine to provide cylindrospermopsin substructure 3 .*; *Please refer to dissertation for diagrams.