(2R,3S)-2-Benzyloxycarbonylamino-3-hydroxy-butyric acid 3-methyl-oxetan-3-ylmethyl ester

4-(3,5-Difluoro-benzyloxy)-N-[(1R,2S)-2-hydroxy-1-(4-methyl-2,6,7-trioxa-bicyclo[2.2.2]oct-1-yl)-propyl]-benzenesulfonamide

(2R,3S)-1-[4-(2-Ethyl-benzyloxy)-benzenesulfonyl]-3-methyl-2-(4-methyl-2,6,7-trioxa-bicyclo[2.2.2]oct-1-yl)-piperazine