Several 2′- and 2″-O-acylated maltotrioside derivatives have been prepared as substrates for use in fluorescence-quenched assays of α-amylase. These maltotriosides carry a quenching group [2-(4-hydroxy-3-nitrophenyl)ethyl] at the reducing end and a fluorescent donor (2-aminobenzoyl) at either of the non-reducing D-glucose units. The quenching groups were introduced via silver triflate-promoted glycosylation, whilst several methods were investigated for the selective introduction of the fluorescent group. Attempted enzymic acylation of the maltotriosides with subtilisin in neat dimethylformamide gave the 2′- and 2″-O-acylated derivatives as the major products. These were shown to be the products of chemical rather than enzymic acylation, in contrast to the analogous literature reaction with maltotriose. Intramolecular quenching of the compounds was demonstrated by measuring the increase in fluorescence upon hydrolysis.