Semisynthesis and antiplasmodial activity of the quinoline alkaloid aurachin E.

A one-step synthesis of the rare aurachin E (1) from the easily accessible aurachin C (2) and cyanogen bromide is described. 3-Bromocarbamoylquinoline (5) is formed in a side reaction with concomitant loss of the 3-farnesyl residue. In an alternative approach, aurachin D (3) was reacted with phosgene and sodium azide to form the imidazolone ring of 1 via N-acylation.