Highly Regio- and Stereoselective Synthesis of Tetracyclic Indoleno­isoxazolidines via Intramolecular 1,3-Dipolar Nitrone Cycloadditions

A facile method for the simple synthesis of tetracyclic indoloisoxazolidine­ frameworks from Baylis–Hillman derivatives through formation of nitrones in situ followed by an intramolecular [3+2]-dipolar cycloaddition reaction sequence is described. High regio- and stereoselectivity, excellent yields, together with the creation of two rings and three contiguous stereogenic centers including one all carbon quaternary center, are the salient features of the present method.