The synthesis of two polyhydroxylatedindolizidines as potenticial glycosidase inhibitors is reported. The piperidine ring was formed by an intramolecular Mannich-type reaction between ethyl trans-4-oxo-2-butenoate and the two β-amino ketones (–)-1-(2-methyl-1,3-dioxan-2-yl)propan-2-amine and(+)-1-(benzyloxymethyl)-2-(2-methyl-1,3-dioxan-2-yl)ethylamine. The synthesis of this amine was performed in