trichorabdal A

(1S,2R,4'aβ,7'R,9'aS)-4'a,5',6',7',8',9'-Hexahydro-5'α-hydroxy-3,3-dimethyl-8'-methylene-1',9'-dioxospiro[cyclohexane-1,4'(3'H)-[1H-7,9a]-methanocyclohepta[c]pyran]-2α-carbaldehyde