toluene-4-sulfonic acid 2-(5-tert-butoxycarbonylamino-2,2-dimethyl-[1,3]dioxan-4-yl)-propyl ester

3-hydroxy-2-hydroxymethyl-4-methyl-pyrrolidine-1-carboxylic acid tert-butyl ester

2,2,7-trimethyl-tetrahydro-[1,3]dioxino[5,4-b]pyrrole-5-carboxylic acid tert-butyl ester

2-(tert-butyl-dimethyl-silanyloxymethyl)-3-hydroxy-4-methyl-pyrrolidine-1-carboxylic acid tert-butyl ester

[4-(2-hydroxy-1-methyl-ethyl)-2,2-dimethyl-[1,3]dioxan-5-yl]-carbamic acid tert-butyl ester