Synthesis and anticancer activity of asparagine analogs.

A series of 11 asparagines substituted on N4 was prepared and evaluated for their ability to inhibit the growth of L5178Y leukemia cell cultures. These cells require an exogenous source of L-asparagine and should be sensitive to an asparagine antimetabolite. The compounds were prepared by reaction of phthalylaspartic anhydride with a primary or secondary amine, followed by removal of the phthalyl group with hydrazine. One compound, N,N-dibenzylasparagine, showed significant activity. Additional study of asparagine derivatives bearing large, lipophilic groups at N4 is warranted.