is enantiomer of (S)-mevalonolactone (+)-(S)-mevalonolactone (4S)-4-hydroxy-4-methyltetrahydro-2H-pyran-2-one A 4-hydroxy-4-methyloxan-2-one that has (<i>S</i>)-configuration. (4S)-4-hydroxy-4-methyloxan-2-one L-mevalonolactone (4S)-4-hydroxy-4-methyltetrahydro-2H-pyran-2-one S-mevalonolactone (S)-(+)-mevalolactone (+)-mevalolactone (+)-(S)-mevalonic acid lactone (+)-mevalonolactone (4S)-tetrahydro-4-hydroxy-4-methyl-2H-pyran-2-one (R)-mevalonolactone 4-hydroxy-4-methyloxan-2-one