(7-methoxycarbonyl-7-methyl-2-oxo-4-phenyl-hexahydro-benzofuran-7a-yl)-acetic acid ethyl ester
(3-methoxycarbonyl-3-methyl-2-oxo-6-phenyl-cyclohexyl)-acetic acid methyl ester
diazomethane
(2-ethoxycarbonylmethylene-3-methoxycarbonyl-3-methyl-6-phenyl-cyclohexyl)-acetic acid