Aplysiasecosterol A, a 9,11-secosterol compound, has a unique tricyclic γ-diketone skeleton including a hemiacetal. The novel tricyclic core of aplysiasecosterol A is constructed by using intramolecular radical cyclization as a key step.

The concise total synthesis of an unusual alkaloid, aplaminal, has been accomplished.

The total synthesis of aplaminal having a unique triazabicyclo[3.2.1]octane skeleton was accomplished using biomimetic oxidative cyclization as a key reaction. This total synthesis enabled us to prepare aplaminal analogs with a variety of substituents at the para-position in the aromatic ring. We found that an electron-donating group at the para-position enhances cytotoxicity and a hydrogen bond donor at the para-position is suitable for cytotoxicity.