3-(2-Hydroxy-2-methylpropyl)-4-methyl-4-pentanolide

5,6-二氢-2H-吡喃-2-酮

4-(2-hydroxyethyl)-5,5-dimethyldihydrofuran-2(3H)-one

5,5-dimethyltetrahydro-2-oxofuran-4-ylacetic acid,