Synthesis and structural study of cyclic 5-aminovaleric acid-linked beta-Ala-beta-Ala dipeptides.

5-Aminovaleric acid and ornithine were evaluated as linkers for the cyclization of beta-dipeptides. Two linked examples of beta-Ala-beta-Ala were prepared by standard coupling methods and their conformations probed by NMR, CD, and computational means. The data suggest that these non- or monosubstituted versions of the target compounds are flexible in solution.