2,7-Dioxabicyclo[3.2.1]octan-6-ol,8-(decahydro-4,4,7a-trimethyl-1aH-cyclopropa[a]naphthalen-1a-yl)-, acetate, [1a,5a,6a,8R*(1aS*,3aS*,7aS*,7bR*)]-