Reactions of 16-Nitroindolenines of the Vincadifformine Type
摘要:
The reactivity of 16-nitroindolenine (4), a byproduct of the aromatic nitration of vincadifformine (1), has been studied. In TFA 4 yielded 10-nitrovincadifformine (3) whereas acid hydrolytic treatment led to the tetracyclic oxindole structure (8) by cleavage of the 2-16 bond. Reduction of 4 (SnCl2 or hydrogenolysis) allowed recovery of 1 in good yield.