19833-47-7 BRN 0655115 Hydroxyaspergillic acid Pyrazinemethanol, alpha-ethyl-6-hydroxy-5-alpha-methyl-5-(2-methylpropyl)-, 1-oxide Pyrazinemethanol, alpha-ethyl-6-hydroxy-5-isobutyl-alpha-methyl-, 1-oxide alpha-Ethyl-6-hydroxy-5-isobutyl-alpha-methylpyrazinemethanol 1-oxide