(2''S,3aR,6S,7aR)-3''-acetyl-3a,7a-dihydro-2,2,2'-2',-tetramethyl-5'-(4-bromophenyl)-spiro(spiro(1,3-dioxolo(4,5-D)-pyrane-6(7H),5'(4'H)-1',3'-dioxolo)-7(6H),2''(3''H)-(1,3,4)-oxadiazole)
(2''s,3ar,6s,7ar)-3''-acetyl-3a,7a-dihydro-2,2,2'-2',-tetramethyl-5'-(4-bromophenyl)-spiro(spiro(1,3-dioxolo(4,5-d)-pyrane-6(7h),5'(4'h)-1',3'-dioxolo)-7(6h),2''(3''h)-(1,3,4)-oxadiazole)