Studies on the Synthesis and Bioactivities of 4-Amino Derivatives of Tetramic Acid

In order to study the potential bioactivities of 4-amino tetramic acid derivatives, the 4-amination products of pyrrolidine-2,4-diones (5) and 4-hydroxy-2-oxo-2,5-dihydro-1H-pyrrole-3-carboxylates (4) were prepared. The 4-amination of 5 took place in high yield when catalyzed by acetic acid, whereas the 4-amination of 4 was achieved through a 4-ethoxy intermediate, which was prepared by acidic etherification. Their herbicidal, fungicidal, insecticidal, and antitumor activities were tested. The bioassays showed that two of the compounds exhibited good herbicidal activity against dicot Arabidopsis thaliana at a concentration of 10 mu g/mL, and one compound gave instinct fungicidal activity against Pythium sp. at a concentration of 2 mu g/mL.