rac-10'-ethyl 1'-methyl (2'R,4b'R,7'S,9a'R,10'S)-2'-hydroxy-7'-(methoxymethoxy)-1'-methyl-2',3',4',4b',5',6',7',10'-octahydro-1'H,9'H-spiro[[1,3]dioxolane-2,8'-[7,9a]methanobenzo[a]azulene]-1',10'-dicarboxylate

(+/-)-(1α,2α,4aα,4bβ,10β)-8,8-(Ethylenedioxy)-2,7-dihydroxy-10-(methoxycarbonyl)-1-methylgibbane-1,4a-carbolactone

(+/-)-(1α,2α,4aα,4bβ,10α)-2-(Benzoyloxy)-10-(ethoxycarbonyl)-8,8-(ethylenedioxy)-7-hydroxy-1-methylgibbane-1,4a-carbolactone

(+/-)-(1α,2α,4aα,4bβ,10β)-2-(Benzoyloxy)-10-(ethoxycarbonyl)-8,8-(ethylenedioxy)-7-hydroxy-1-methylgibbane-1,4a-carbolactone

(+/-)-(1α,2α,4bβ,10α)-Ethyl 8,8-(ethylenedioxy)-1-(methoxycarbonyl)-7-<(methoxymethyl)oxy>-1-methyl-2-(4-toluolsulfonyloxy)gibb-4a(10a)-ene-10-carboxylate