Twenty-four derivatives of N, N-dimethylbarbituric acid 1-24 were screened for their DPPH radical scavenging activity. These compounds showed an excellent antioxidant activity. A structure-activity relationship has been discussed, while all the synthetic compounds were characterized by spectroscopic techniques and elemental analysis.
![5-[(3,4-dihydroxyphenyl)methylidene]-1,3-dimethyl-1,3-diazinane-2,4,6-trione Structure](https://image.chemsrc.com/caspic/139/300589-01-9.png)
![1,3-dimethyl-5-[(3-nitrophenyl)methylidene]-1,3-diazinane-2,4,6-trione Structure](https://image.chemsrc.com/caspic/053/57270-90-3.png)