The three chiral building blocks ethyl 4,5-O-isopropylidene-(E)-(S)-4, 5-dihydroxy-2-pentenoate [1,3-dioxolane derivative (E)-(S)-1a], (S)-5-hydroxy-4-pentanolide [(S)-2a], and (S)-5-hydroxy-2-penten-4-olide [(S)-3a] are conveniently prepared from 1,2;5,6-di-O-isopropylidene-D-mannitol (4) via a glycol cleavage and Horner-Emmons reaction sequence.