Synthesis of 10- and 9-membered dilactams derived from aspartic and glutamic acids.

:  9- and 10-membered bridged dipeptides derived from l-aspartic acid and l- or d-glutamic acid were synthesized using aminoacyl incorporation reaction. Key intermediates containing internal pyroglutamyl moiety were prepared via side chain to backbone cyclization of related protected dipeptide derivatives of glutamic acid.