Recent developments in marine indole alkaloid synthesis.

The manzamine alkaloids such as manzamine A, B, and C belongs to a unique family of cyctotoxic beta-carbline linked azacycles, which have been isolated from several marine sponges. Manzamine A has recently been shown to exhibit in vivo antimalarial activity against parasite Plasmodium berghei. Further progress was added recently by the isolation of the new and closely related members such as nakadomarin A, as well as an ingenious proposal for their biosynthetic pathway. Martefragin A, isolated from the Japan sea alga Martensia fragilis Harvey, has been shown to have a potent inhibitory activity against lipid peroxidation. Our recen, efforts to develop total synthesis entries to manzamine A, manzamine B, manzamine C, nakadomarin A, and martefragin A are presented.