Design Synthesis and Investigation of Protein Kinase C Inhibitors: Total Syntheses of (+)-Calphostin D (+)- Phleichrome Cercosporin and New Photoactive Perylenequinones

摘要

The total syntheses of the PKC inhibitors (+)-calphostin D, (+)-phleichrome, cercosporin, and 10 novel perylenequinones are detailed. The highly convergent and flexible strategy developed employed an enantioselective oxidative biaryl coupling and a double cuprate epoxide opening, allowing the selective syntheses of all the possible stereoisomers in pure form. In addition, this strategy permitted rapid access to a broad range of analogs, including those not accessible from the natural products. These compounds provided a powerful means for evaluation of the perylenequinones structural features necessary to PKC activity. Simpler analogs were discovered with superior PKC inhibitory properties and superior photopotentiation in cancer cell lines relative to the more complex natural products.