Two distinct conformations of GABA locked by embedding in the bicyclo[3.1.0]hexane core structure

The bicyclo[3.1.0] system preferentially adopts a boat-shaped conformation, providing an interesting core for the design of both topological and spatial diversity, thus yielding many possibilities for the embedding of 1,3-disubstituted propylene units in various fixed conformations. This is shown for derivatives with embedded GABA subunits in either trans-trans or trans-gauche conformations, as documented by crystal structures of newly synthesized compounds.