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

(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

(2S,6S,8S)-2,8-Bis-(2-benzyloxy-ethyl)-10-triisopropylsilanyloxy-1,7-dioxa-spiro[5.5]undec-10-en-4-one

(2S,4S,6R,8S)-2,8-Bis-(2-benzyloxy-ethyl)-10-triisopropylsilanyloxy-1,7-dioxa-spiro[5.5]undec-10-en-4-ol