benzyl rel(3S,4R)-4-ethoxycarbonylmethyl-3-(2-hydroxyethyl)-piperidine-1-carboxylate

ethyl 3-(2-ethylenedioxyethyl)-4-hydroxypiperidine-1-carboxylate

ethyl 5-((1,3-dioxolan-2-yl)methyl)-7-oxa-3-azabicyclo[4.1.0]heptane-3-carboxylate

benzyl 5-(1,3-dioxolan-2-ylmethyl)-3,4-epoxypiperidine-1-carboxylate

benzyl 3-(1,3-dioxolan-2-ylmethyl)-1,2,3,6-tetrahydropyridine-1-carboxylate