位置選択的α-hydroxyalkylationによるインドールアルカロイドの合成研究

抄録

Ortho-selective α-hydroxyalkylation was one of versatile C-C bond forming reactions and its aromatic version is the most useful method for the preparation of 2-(α-hydroxyalkyl)phenols. Although the low regioselective insertion of carbon unit is usually encountered by phenol derivatives used as the substrates, 5-hydroxyindole derivatives exhibit high selectivity at C-4 position on the indole. Therefore, we attempted to synthesize decursivine analogues, including decursivine, serotobenine, moschaminindolol and flavumindole, from 5-hydroxyindole. Although serotobenine and decursivine have already been synthesized, total synthesis of moschaminindolol and flavumindole have not been achieved. We succeeded in inserting benzylaldehyde at C-4 position on 5-hydroxyindole by α-hydroxyalkylation. At present, modification of C-3 on indole and construction of eight-membered ring are under consideration.