An efficient approach toward virantmycin: stereospecific construction of tetrahydroquinoline ring system employing intramolecular nitrene-addition reaction
An efficient and stereospecific synthesis of the tetrahydroquinoline ring system of the structurally unique alkaloid, virantmycin (1), has been achieved using intramolecular addition reaction of nitrene to olefin as a key step.
a ring inversion occurs in their piperidine ring system and determined the relative stereochemistry by capturing each half-chair conformer as cyclic carbamates 26 and 27, respectively. Utilizing this protocol total syntheses of (±)-1 and its diastereomer (±)-2 have been accomplished and the relative stereochemistry of virantmycin has been established as shown in 1.