Abstract
Ansa-compounds have intriguing molecular structures and highly potent bioactivities. One of the ansa-compounds, kendomycin, has an oxa-metacyclophane skeleton with quinone methide core and a fully substituted tetrahydropyran ring. In contrast to a common synthetic strategy for construction of the ansa-skeleton via elongation of an alkyl chain from an aromatic core followed by macrocyclization, we challenged a new method for construction of the ansa-skeleton via simultaneous macrocyclization and benzannulation (using intramolecular Dötz benzannulation). Understanding the reactivity of various Fischer-type ω-alkynyloxy chromium carbene complexes with kendomycin analogs syntheses led to achievement of the total synthesis of kendomycin. Investigations of structure-activity relationships revealed the need for an ansa-skeleton for antimicrobial activity.
