(2R,3R,4R)-2,3-dihydroxy-5-trityloxy-4-pentanolide

(3R,4R,5R)-4-hydroxy-3-[(1S)-1-hydroxy-1-(3,4-methylenedioxyphenyl)methyl]-5-trityloxymethyldihydro-2(3H)-furanone

(2R,3S,4R)-3-hydroxy-2-phenoxythiocarbonyloxy-5-trityloxy-4-pentanolide

(3R,4R,5R)-4-methoxymethoxy-3-[(1S)-1-methoxymethoxy-1-(3,4-methylenedioxyphenyl)methyl]-5-trityloxymethyldihydro-2(3H)-furanone

(3R,4R)-3-hydroxy-5-trityloxy-4-pentanolide