2,6-Diamino-3,5-diaryl-1,4-pyrazine Derivatives as Novel Antioxidants

Abstract

The coupling of arylboronic acids with 2,6-diamino-3,5-dibromo-1,4-pyrazine (6) gave 2,6-diamino-3,5-diaryl-1,4-pyrazines (7). The reaction of 7 with methyl glyoxal in aqueous EtOH-HCl led to the N,N'-disubstituted products 8, instead of the expected bicyclic imidazolopyrazinones 1. The 2,6-bis[1-(ethoxycarbonyl)ethylamino]-3,5-diaryl-1,4-pyrazines 8 are powerful inhibitors of the AAPH-induced linoleate peroxidation.