Recently we have described the antitumor activities of 2-benzoxazolylhydrazones derived from 2-formyl and 2-acetylpyridines. In search of a more efficacious analogue, compounds in which the 2-acetylpyridine moiety has been replaced by 2-acylpyridine and α-(N)- acetyldiazine/quinoline groups have been synthesized. The 2-acylpyridyl hydrazones inhibited in vitro cell proliferation in the nM range, whereas the hydrazones derived from ...