(3R,3aS,7S,8R,9R,9aR)-8-Bromo-3,9-dimethyl-octahydro-3a,7-methano-cyclopentacycloocten-6-one

(E)-3-((3R,3aS,7S,7aR)-3,7-Dimethyl-1,2,3,4,7,7a-hexahydro-inden-3a-yl)-acrylic acid ethyl ester

(3R,3aR,7R,7aR)-3,7-Dimethyl-6-oxo-octahydro-indene-3a-carboxylic acid methyl ester