1. ing the S-configuration. The bond lengths ribose and the phenyl group were they in
2. of N(2)-C(3) and C(5)-N(6) are 1.29 (M)A the Z-related positions.
3. .31 (1)A respectively and show that the In the light of the determination of the
4. guanidino groups on both of the 5-mem- structure of AOP-1 it would now appear
5. bered rings exist in the exocyclic imino that all of the other derivatives (ROP-1