Expeditious total syntheses of camptothecin and 10-hydroxycamptothecin.

New expeditious total syntheses of (S)-camptothecin (16% overall yield, 95% ee) and (S)-10-hydroxycamptothecin (14% overall yield, 99% ee) have been accomplished, respectively, starting from readily available and inexpensive materials. Development, optimization, and successful application of the cascade reaction consisting of a pyrrolidine-catalyzed Michael addition, an intramolecular aldol condensation, and an oxidative aromatization, the intramolecular oxa Diels-Alder cycloaddition, and the Sharpless asymmetric dihydroxylation make these two new syntheses more efficient and straightforward.