Unprecedented One-Pot Chemocontrolled Entry to Thioxoimidazolidinones and Aminoimidazolones: Synthesis of Kinase Inhibitor Leucettamine B

A novel and highly chemoselective
protocol for the construction
of thioxoimidazolidinone and aminoimidazolone frameworks was explored,
and the influence of the reaction conditions on product formation
was studied to establish two distinct approaches for their selective
formation. In this one-pot reaction, ambient temperature generally
resulted in the formation of thioxoimidazolidinones, whereas microwave
irradiation provided aminoimidazolones exclusively. An attempt to
elucidate the observed chemoselectivity is described, and the products
were confirmed by X-ray studies. One-pot synthesis toward Leucettamine
B, a marine alkaloid, was achieved on the basis of this protocol.