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Studies in our laboratory are directed at the advancement of synthesis, biology, and medicine. This lecture will focus on new transition metal-catalyzed reactions that have been inspired by biologically potent targets such as phorbol and Taxol® and by the more general interest in producing syntheses that are concise, efficient, cost- and resource-effective, environmentally benign, quick, and simple to conductin essence, ideal. A special emphasis in our program is placed on new transition metal-catalyzed reactions that, in the absence of catalyst, would be forbidden or difficult to achieve. We have thus far reported the first examples of intramolecular metal-catalyzed [4+2], [5+2], and [4+4] cycloadditions, reactions that produce 6-, 7-, and 8-membered rings, respectively. Recent advances in our [5+2] cycloaddition studies will be presented, including new catalysts for relative and absolute stereochemical control. We will also describe recyclable catalysts that can be used in water, thereby minimizing cost and environmental concerns about solvent waste streams. New multicomponent reactions will also be presented. Finally, we will report a new [6+2] cycloaddition that produces an 8-membered ring.

[reaction: see text] An efficient synthetic route to the ABC tricyclic core of 1alpha-alkyldaphnanes has been developed. The conformational bias imparted by the C6-C9 oxo-bridge of BC-ring system 12 was used to elaborate the ABC-ring system precursor including the introduction of the beta-C5 hydroxyl group. A completely diastereoselective palladium-catalyzed enyne cyclization was then employed to establish the A-ring with a C1 appendage.

The emergence and evolution of new immunological cancer therapies has sparked a rapidly growing interest in discovering novel pathways to treat cancer. Toward this aim, a novel series of pyrrolidine derivatives (compound ) were identified as potent inhibitors of ERK1/2 with excellent kinase selectivity and dual mechanism of action but suffered from poor pharmacokinetics (PK). The challenge of PK was overcome by the discovery of a novel 3()-thiomethyl pyrrolidine analog . Lead optimization through focused structure-activity relationship led to the discovery of a clinical candidate suitable for twice daily oral dosing as a potential new cancer therapeutic.