Synthesis, trehalase hydrolytic resistance and inhibition properties of 4- and 6-substituted trehalose derivatives

Although trehalose has recently gained interest because of its pharmaceutical potential, its clinical use is hampered due to its low bioavailability. Hence, hydrolysis-resistant trehalose analogues retaining biological activity could be of interest. In this study, 34 4- and 6-O-substituted trehalose derivatives were synthesised using an ether- or carbamate-type linkage. Their hydrolysis susceptibility and inhibitory properties were determined against two trehalases, i.e. porcine kidney and Mycobacterium smegmatis. With the exception of three weakly hydrolysable 6-O-alkyl derivatives, the compounds generally showed to be completely resistant. Moreover, a number of derivatives was shown to be an inhibitor of one or both of these trehalases. For the strongest inhibitors of porcine kidney trehalase IC(50) values of around 10 mM could be determined, whereas several compounds displayed sub-mM IC(50) against M. smegmatis trehalase. Dockings studies were performed to explain the observed influence of the substitution pattern on the inhibitory activity towards porcine kidney trehalase.