A 1,3-dipolar cycloaddition-annulation protocol for the expedient regio-, stereo- and product-selective construction of novel hybrid heterocycles comprising seven rings and seven contiguous stereocentres

A facile, one-pot, three-component, [3+2]-cycloaddition/annulation domino protocol for the synthesis of a series of hexacyclic cage systems in good to excellent yields, and their subsequent acid-mediated reactions with paraformaldehyde affording an unusual, rare class of pyrrolo[1,2-c]oxazolidine fused heptacyclic cage systems is described.