Biomimetic total synthesis of bisorbicillinol, bisorbibutenolide, trichodimerol, and designed analogues of the bisorbicillinoids

The bisorbicillinoids are a growing class of novel natural products endowed with unique biological activity and are associated with fascinating hypotheses for their biosynthesis. A full account of our biomimetic explorations toward the bisorbicillinoids including the total syntheses of bisorbicillinol (1), bisortibutenolide (2), and trichodimerol (4) from sorbicillin (3) is disclosed. Utilizing the novel dimerization reactions discovered and fine-tuned en route to 1 and 4, several analogues of these natural products have been synthesized. Furthermore, studies on the scope of these novel cycloaddition reactions and the isolation of a number of unexpected products along with proposed mechanisms for their formation are reported. These findings add to our knowledge of the largely unexplored chemistry of o-quinols and related aromatic systems.