Total Synthesis of Bulgarein

Here we report an efficient and short total synthesis of bulgarein (1), a natural compound from Bulgaria inquinans with cytotoxic activity. Key steps in the total synthesis are a SUZUKI-MIYAURA coupling reaction of two substituted naphthalene derivates followed by a polyphosphoric acid (PPA) mediated condensation reaction to form the benzo[j]fluoranthene skeleton. Bulgarein (1) was achieved over 4 steps with an overall yield of 25%.

Automated summary

In this study, an efficient and short total synthesis method of bulgarein (1), a natural compound with cytotoxic activity in Bulgaria inquinans, was reported. The key steps in the synthesis include a SUZUKI-MIYAURA coupling reaction of two substituted naphthalene derivatives and a polyphosphoric acid (PPA) mediated condensation reaction to form the benzo[j]fluoranthene skeleton. Bulgarein (1) was synthesized in 4 steps with an overall yield of 25%.