Synthesis of tenuazonic acid analogues

The synthesis of two 1.5-diaryltetramic acids, aryl analogues of tenuazonic acid, is described. The reactivity of position 4 of these tetramic acids towards primary and secondary amines, and o-methylation led to the synthesis of 4-substituted-delta3-pyrroline-2-one. Further, reactivity of position 3 has been indicated by the formation of 3-arylidenepyrrolidine-2.4-diones and by diazo-coupling. The structures assigned to the new compounds are substantiated by IR and NMR data.