(3S,6S,6aS,7S,9aS)-7-[(2R,3R)-4-(benzyloxy)-3-{[tert-butyl(dimethyl)silyl]oxy}-2-methylbutyl]-3-tert-butyl-6a-hydroxy-6-methyldihydrofuro[3',4':2,3]pyrrolo[1,2-c][1,3]oxazole-5,9(6H)-dione

(3S,6R,6aS,7S,9aS)-7-[(2R,3R)-4-(benzyloxy)-3-{[tert-butyl(dimethyl)silyl]oxy}-2-methylbutyl]-3-tert-butyl-6a-hydroxy-6-methyldihydrofuro[3',4':2,3]pyrrolo[1,2-c][1,3]oxazole-5,9(6H)-dione

(3R,3aS,4S,6aS)-4-{(2R,3R)-4-(benzyloxy)-2-methyl-3-[triethylsilyloxy]butyl}-3a-hydroxy-3-methyl-6a{triethylsilyloxymethyl}dihydro-1H-furo[3,4-b]pyrrole-2,6(3H,4H)-dione

(3R,3aS,4S,6aS)-4-{(2R,3R)-4-benzyloxy-2-methyl-3-[triethylsilyloxy]butyl}-3-methyl-6a-{[triethylsilyloxy]methyl}-3a-[trimethylsilyloxy]dihydro-1H-furo[3,4-b]pyrrole-2,6(3H,4H)-dione

(3R,3aS,4S,6aS)-4-((2R,3R)-4-(benzyloxy)-2-methyl-3-((trimethylsilyl)oxy)butyl)-3-methyl-6a-(((triethylsilyl)oxy)methyl)-3a-((trimethylsilyl)oxy)tetrahydro-6H-furo[3,4-b]pyrrole-2,6(3H)-dione