(4-Hydroxy-2,5,7-trimethyl-2H-pyrido(3,2-e)-1,2-thiazin-3-yl)phenylmethanone S,S-dioxide 108586-76-1 Methanone, (4-hydroxy-2,5,7-trimethyl-2H-pyrido(3,2-e)-1,2-thiazin-3-yl)phenyl-, S,S-dioxide