(2R,3S)-3-(tert-Butyl-dimethyl-silanyloxy)-4-[(2S,3S,4S,5S,6R,9S,11S)-4-(tert-butyl-dimethyl-silanyloxy)-9-ethyl-3,5,11-trimethyl-8-oxo-1-oxa-7-aza-spiro[5.5]undec-2-yl]-2-methyl-butyraldehyde

(2S,4S,6S)-6-[(4S,5S,6S)-6-(2-Benzyloxy-ethyl)-2,2,5-trimethyl-[1,3]dioxan-4-yl]-2-ethyl-4-methyl-5-oxo-heptanoic acid amide