Spiro(12H-6,13a-epoxybenzo(4,5)cyclodeca(1,2-b)furan-12,2'-oxiran)-2(1H)-one, 7,8,9,13-tetrakis(acetyloxy)-4-chlorododecahydro-1,8a-dimethyl-5-methylene-, (1alpha,3abeta,4alpha,6alpha,7alpha,8beta,8abeta,9alpha,12alpha,12aalpha,13.beta)