The synthesis of tetracycles of type 1 is described. Both la and lb are converted into the estrogen-like compounds 12a and 12bvia the corresponding a-epoxides. The ß-epoxides yield mixtures of dienes. The stereochemical influence of the base on the alkene precursors for tetracyclic compounds, formed under Wittig-Schlosser conditions, has been established. Finally, evidence is offered for the trans,anti,trans geometry in the tetracyclic molecules under discussion.