Benzothiophene and naphthalene derived constrained SERMs.

For selective estrogen receptor modulators (SERMs), the orientation of the basic side chain relative to the SERM core has a significant impact on function. The synthesis and biological evaluation of two series of SERMs are disclosed, where the ligand side chain is constrained to adopt a defined orientation. Compounds where the side chain is forced into the plane of the SERM core have a different profile compared to those compounds where the side chain is pseudo-orthogonal, particularly with regard to antagonism of estradiol action on an Ishikawa uterine cell line.