Alkaloids from Mackinlaya species and synthetic mackinazolinone derivatives: An overview.

Mackinazolinone is the main alkaloid isolated from plants of the genus Mackinlaya, essentially distributed in tropical Asia and Australia. There are five Mackinlaya species all containing bioactive alkaloids with a tetrahydropyridoquinazolinone core such as mackinazoline (1) and mackinazolinone (2). The present review retraces the origin of mackinazolinone and compares the different chemical routes to synthesize the natural product, through different methods including classical batch synthesis, solid-phase supported synthesis, microwaved irradiation and photochemistry.