Asymmetric Total Synthesis of Cylindrocyclophanes A and F through Cyclodimerization and a Ramberg-Bäcklund Reaction and Studies Directed Towards the Total Synthesis of CJ-16, 264 /
- Author(s): Korman, Henry
- et al.
Cylindrocyclophanes A and F are naturally occurring cyclophanes with beautiful molecular architectures and important biological properties that have inspired numerous syntheses. Chapter 1 details the isolation and biological properties of these molecules, our retrosynthetic analysis, and asymmetric total syntheses of these molecules. The highlights of this synthesis includes a "head-to-tail" dimerization reaction and a Ramberg- Bäcklund olefination reaction to generate the [7.7]- paracyclophane found in these molecules. CJ-16,264, UCS1025A, and pyrrolizilactone belong to a unique class of natural products isolated from fungi, each containing a [gamma]-hydroxypyrrolizidinone adjoined to a decalin. Their unique architectures, as well as their amazing biological activities, has inspired several syntheses of UCS1025A. There has been no report, to the best of our knowledge, of a successful synthesis of CJ-16,264 or pyrrolizilactone. Chapter 2 describes the isolation and biological properties of these molecules, our retrosynthetic analysis, the synthesis of (±)-1-epi-CJ-16 ,264 and our significant contributions towards the synthesis CJ-16,264. The highlights of this synthesis include a double exo-selective IMDA (intramolecular Diels- Alder) reaction and a stereoselective Reformatsky-type cross coupling to generate the common scaffold of these molecules