The invention relates to novel 18-norsteroids (gonatrienes) of general formula (I), wherein R , R , R , R , R , R , R , R , R , R , R , R , R , R and R have the meaning cited in the description, and to the use of said compounds as pharmaceutical active ingredients. Said compounds exhibit a high affinity in vitro for estrogen receptor preparations of rat prostate and in an estrogen receptor preparation of rat uterus. Said compounds exhibit in vivo preferential activity on bones as compared to the uterus and/or significant activity with regard to stimulating the expression of 5HT2a-receptors and transporter molecules. The invention also relates to the production of said compounds, therapeutic use and galenic form of said compounds contained in the novel compounds of invention. The invention also relates to utilization of steroids based on the gonatriene molecular skeleton in order to treat estrogen deficiency-induced diseases and disorders, in addition to the use of said gonatriene structural component in the total structure of compounds which dissociate to produce enhanced estrogen activity in bone as compared to the uterus.