[(2R,4S,6S,8S,10S)-4-(tert-Butyl-dimethyl-silanyloxy)-10-methyl-8-((R)-3-methyl-2-methylene-4-triethylsilanyloxy-butyl)-10-triethylsilanyloxy-1,7-dioxa-spiro[5.5]undec-2-yl]-acetic acid tert-butyl ester

(2S,4S,6R,8S,10S)-2,8-Bis-(2-benzyloxy-ethyl)-10-(tert-butyl-dimethyl-silanyloxy)-4-methyl-1,7-dioxa-spiro[5.5]undecan-4-ol

(2S,6R,8S,10S)-2,8-Bis-(2-benzyloxy-ethyl)-10-hydroxy-1,7-dioxa-spiro[5.5]undecan-4-one