Phenylbenzenesulfonates and -sulfonamides as 17β-hydroxysteroid dehydrogenase type 2 inhibitors: Synthesis and SAR-analysis.

17β-Hydroxysteroid dehydrogenase type 2 (17β-HSD2) converts the potent estrogen estradiol into the weakly active keto form estrone. Because of its expression in bone, inhibition of 17β-HSD2 provides an attractive strategy for the treatment of osteoporosis, a condition that is often caused by a decrease of the active sex steroids. Currently, there are no drugs on the market targeting 17β-HSD2, but in multiple studies, synthesis and biological evaluation of promising 17β-HSD2 inhibitors have been reported. Our previous work led to the identification of phenylbenzenesulfonamides and -sulfonates as new 17β-HSD2 inhibitors by ligand-based pharmacophore modeling and virtual screening. In this study, new molecules representing this scaffold were synthesized and tested in vitro for their 17β-HSD2 activity to derive more profound structure-activity relationship rules.