Biexcisusin C, (rel)-

(1S,1′S,3S,3′S,4R,4′R,6S,6′S,8S,8′S,9R,9′R,10S,10′S,11S,11′S,13R,13′R,14S)-3,3′,8,8′-Tetrahydroxy-5,5,5′,5′,9,9′-hexamethyl-14′,15,19′-trioxo-18′-oxaspiro[tetracyclo[11.2.1.0~1,10~.0~4,9~]hexadecane-1 4,17′-tetracyclo[11.6.1.0~1,10~.0~4,9~]icosane]-6,6′,11,11′-tetrayl tetraacetate

Biexcisusin C, (rel)-