Addition of TMSCN to chiral ketimines derived from isatin. Synthesis of an oxindole-based peptidomimetic and a bioactive spirohydantoin.

We investigated the Strecker-type reaction of isatin derived chiral ketimines with TMSCN in the presence of a Lewis acid. The desired α-amino nitriles have been obtained in good yields with moderate diastereoselectivity. Further elaboration of the cyanide group allowed the preparation of a new oxindole-based peptidomimetic and a pharmaceutically relevant spirohydantoin.