1. Field of the Invention
The subject of the present invention is a method for preparing 19-norsteroid compounds, and the intermediate compounds prepared during the use of this method.
2. Description of the Art
Osteoporosis is a bone disease which affects 50 million people worldwide, more particularly women. Its development is linked to age and begins most often after the menopause. This disease is characterized by a reduction in bone density, causes deformations, vertebral compression and in time spontaneous fractures. Osteoporosis therefore represents a serious challenge for public health. The main treatment consists in taking estrogens regularly, which reduces bone loss but which, nevertheless, may be accompanied by certain side effects (bleeding, hot flushes, risk of breast cancer, and the like). A novel series of molecules called SERM (Selective Estrogen Receptor Modulator) allows the treatment of osteoporosis while avoiding some of the side effects (WO98/45316, WO99/67274, WO98/28324, WO99/25725, EP605193, WO02/100880).
The subject of the present application is the development of a novel method for preparing a key intermediate (compound of formula I) in the synthesis of certain estrogen derivatives having a dissociated activity.
All of the references described herein are incorporated herein by reference in their entirety.