((4aR,5R,7R,8aS)-7-Benzyloxymethyl-2,2,4a-trimethyl-hexahydro-1,6-dioxa-2-sila-naphthalen-5-yl)-acetic acid ethyl ester

(1S,9R,11R,12R,13R,21R,23R,24R)-11-(tert-butyldimethylsilanyloxy)-24-(tert-butyldimethylsilanyloxymethyl)-23-(2-hydroxyethyl)-12,15,24-trimethyl-2,22,26-trioxatricyclo[19.3.1.19,13]-(4E,6E,14Z,16E,19E)-hexacosapentaen-3-one

2,2-Dimethyl-propionic acid 2-((4aR,5R,7R,8aS)-7-hydroxymethyl-2,2,4a-trimethyl-tetrahydro-pyrano[4,3-d][1,3]dioxin-5-yl)-ethyl ester