An efficient total synthesis of optically active tetrodotoxin from levoglucosenone.

Tetrodotoxin, a toxic principal of puffer-fish poisoning, is one of the most famous marine natural products, and has been known as a formidable synthetic target in synthesis owing to its multifunctional structure and unusual chemical properties. From the perspective of supplying tetrodotoxin derivatives such as labeled molecules for biochemical research, we have completed our second total synthesis of tetrodotoxin from a synthetic intermediate for 11-deoxytetrodotoxin, which was previously prepared from levoglucosenone as a chiral starting material in this laboratory. This paper discloses the details of the total synthesis with special reference to significant influences on the neighboring functional groups found in the installation of guanidine. The established route should allow us to prepare the tetrodotoxin-related compounds required for biochemical studies.