THE SYNTHESIS OF A NUMBER OF ETHOXYQUIN ANALOGS AND THEIR EVALUATION AS ANTIOXIDANTS IN FISH OIL

The synthesis, physical characteristics and spectral data of six alkoxy derivatives of 1,2-dihydro-2,2,4-trimethylquinoline are described. The compounds which are analogues of the antioxidant ethoxyquin (1,2-dihydro-6-ethoxy-2,2,4-trimethylquinoline) were tested for antioxidant activity. It was found that the compounds which had a methoxy, n-propoxy or isopropoxy group in the 6-position of the molecule showed activity comparable to that of ethoxyquin, while compounds with a methoxy or ethoxy group in the 8-position had virtually no antioxidant activity. The substance with methoxy groups in both 6 and 8 positions showed a diminished antioxidant activity compared to ethoxyquin.