Enzymatic route to alkyl glycosides having oligomeric head groups

Abstract

Cyclodextrin glycosyl transferase (CGTase) from Bacillus macerans was used to catalyse the coupling of α-cyclodextrin to alkyl β-glycosides. The acceptor substrate dodecyl β-maltoside was thus converted to dodecyl β-D-maltooctaoside. Further coupling steps and disproportionation reactions occurred, but by optimisation of the reaction time, a yield of 50% of the primary coupling product was obtained. The method worked well for a range of acceptors with different length of the carbohydrate part (1–3 glucose residues) and the hydrocarbon chain (10–14 carbon atoms). With respect to the principles of green chemistry, the method is superior to previously used methods involving protection/deprotection reactions.