Specific, uncompetitive inhibition of β-galactosidases by a 5,6-isopropylidenedioxyfuro[2,3-d]isoxazole-3-methanol derivative

(−)-(3aS,5S,6S,6aR)-3a,5,6,6a-Tetrahydro-5,6-isopropylidenedioxyfuro[2,3-d]isoxazole-3-methanol ((−)-5) has been tested toward 25 glycohydrolases and found to inhibit β-galactosidase from Aspergillus niger (Ki = 18 μM) and that from Aspergillus orizae (Ki = 72 μM). Hydrolysis of the acetonide or exchange of CH2OH group for a CHO. CH2OMe or a CH2OMOM group suppresses the inhibitory activity.