Propionic acid (1S,2R,7R,9R,11R)-2-hydroxymethyl-1,5-dimethyl-12-methylene-8-oxa-tricyclo[7.2.1.02,7]dodec-5-en-11-yl ester

(1S,2R,7R,9R,11R)-2-(tert-Butyl-dimethyl-silanyloxymethyl)-1,5-dimethyl-12-methylene-8-oxa-tricyclo[7.2.1.02,7]dodec-5-en-11-ol