Studies on the chemical constituents of rutaceous plants. Part 62. Efficient synthesis of fagaronine, a phenolic benzo[c]phenanthridine alkaloid with antileukaemic activity

Fagaronine (2), an antileukaemic hydroxybenzo[c]phenanthridine alkaloid, has been synthesized from the chalcone (4a) according to the synthetic sequence (Schemes 1–4). During the synthesis, the hydroxy group was protected in the form of its isopropoxy derivative.