New α-galactosidase-inhibiting aminohydroxycyclopentanes

A set of cyclopentanoid α-galactosidase ligands was prepared from a partially protected ω-eno-aldose <i>via</i> a reliable (2 + 3)-cycloaddition protocol with slightly modified conditions. The obtained <i>N</i>-benzylisoxazolidine ring was selectively opened and the configuration of the hydroxymethylgroup was inverted. Consecutive deprotection provided an aminocyclopentane, which was <i>N</i>-alkylated to furnish a set of potential α-galactosidase inhibitors. Their glycosidase inhibitory activities were screened with a panel of standard glycosidases of biological significance.