The ring-opening polymerization, triggered
by a Lewis acid without the presence of the linker, was previously proposed to be terminated
by water at the reducing end. However, in the present study, the results suggest that the
polymerization may also be initiated from the reducing end by the attack of the hydroxyl head
group of a short chain alkyl thiol linker. After that, an elongation of the growing polysaccharide
may be achieved via the propagation to the non-reducing end.