Synthesis of 4-Amino-2(5H)-furanones through Intra- and Intermolecular Nitrile Addition of Ester Enolates. Construction of Carbon Framework of an Antitumor Antibiotic Basidalin

Two new routes to 4-amino-2(5H)-furanones are disclosed. The one is based on the reaction of a magnesium enolate of t-butyl acetate or propionate with O-protected cyanohydrins followed by acid-treatment which effects hydrolysis of the ester group, deprotection, olefin isomerization and lactonization all in a single operation. The other is base-induced ringclosure of α-acyloxy nitriles. The two methods are applied to construction of the carbon framework of an antitumor antibiotic basidalin.