Asymmetric resolution and molecular recognition. Part 2. The X-ray crystal structures of ephedrine–N-benzyloxycarbonyl-L-leucine and ephedrine–N-acetyl-L-valine

Abstract

The crystal structures of ephedrine–N-benzyloxycarbonyl-L-leucine (1)(P2₁2₁2₁, a= 14.067, b= 29.982, c= 5.737 Å) and ephedrine–N-acetyl-L-valine monohydrate (2)(P2₁2₁2₁, a= 13.501, b= 19.173, c= 7.694 Å) are reported and the conformations of the ephedrine moieties are compared with those in other structures. Charge–charge interactions, hydrogen bonding, and specific phenyl-phenyl interactions play a part in these stereospecific crystallisations.