Hydroxyaspergillic acid

1-Hydroxy-3-isobutyl-6-(1-hydroxy-1-methylpropyl)pyrazine-2(1H)-one

1-hydroxy-6-(1-hydroxy-1-methylpropyl)-3-(2-methylpropyl)-2(1H)-pyrazinone

1-Hydroxy-3-(2-methylpropyl)-6-(1-methyl-1-hydroxypropyl)pyrazine-2(1H)-one