Synthetic Study Towards the Total Synthesis of Neocarzinostatin Chromophore

The chromophores of enediyne chromoprotein anticancer antibiotics have attracted a lot of efforts towards the total synthesis. Very recently, Myers group^1] reported the first synthesis of neocarzinostatin chromophore 1. The key point of our approach for the total synthesis of this compound is to construct the highly strained and unstable bicyclic7.3.0]epoxyenediyne core at the late stage of synthesis using an intramolecular acetylide aldehyde ring closure. The proposed approach is illustrated retrosynthetically as follows (Scheme).