2,5-Dihydroxy-.alpha.-toluic acid 2,5-Dihydroxyphenylacetic acid 451-13-8 Acetic acid, (2,5-dihydroxyphenyl)- Alcapton Benzeneacetic acid, 2,5-dihydroxy- Homogentisate acid Homogentisic acid Homogentisinic acid NSC88940