Novel 4,5-seco-estrane-3,5,17-trione derivatives of the formula ##STR1## wherein R.sub.1 is alkyl of 1 to 3 carbon atoms, R.sub.2 is selected from the group consisting of hydrogen and alkyl of 1 to 5 carbon atoms and K and K' are individually blocked ketones in the form of ketals which are intermediates for the preparation of therapeutically active steroids and their preparation and novel intermediates.
