4-Methylphenylglyoxal pyrazinamido-hemiacetal 42177-48-0 BRN 0811231 N-(1-Hydroxy-2-(4-methylphenyl)-2-oxoethyl)pyrazinecarboxamide Pyrazinecarboxamide, N-(1-hydroxy-2-(4-methylphenyl)-2-oxoethyl)-