Fused pyridine derivativesFused pyridine derivatives R 0450 Cascade Reaction of Imines with Phenylsulfinylallene. X-Ray Structure of the Product and Its Formation Mechanism. -On the basis of theoretical calculations and some further experiments the possible mechanism of this cascade reaction yielding (III) is discussed. The structure of compound (III) is determined by X-ray analysis. -(OISO, S.; YOSHITAKE, Y.; ETO, M.; HARANO*, K.; Chem.