No abstract

Elevated aldosterone levels are key effectors for the development and progression of congestive heart failure and myocardial fibrosis. Recently, we proposed inhibition of aldosterone synthase (CYP11B2) as an innovative strategy for the treatment of these diseases. In this study, the synthesis and biological evaluation of E- and Z-(pyridylmethylene)tetrahydronaphthalenes and -indanes (1a,b-38a) is described. The activity of the compounds was determined using human CYP11B2, and the selectivity was evaluated toward the human steroidogenic enzymes CYP11B1, CYP19, and CYP17. The biological results revealed a few rather selective inhibitors of CYP11B1, some compounds inhibiting both CYP11B1 and CYP11B2, and a large number of highly selective inhibitors of CYP11B2. The most active inhibitor was the 3-pyridyl compound 5a (IC(50) = 7 nM). The pyrimidyl-substituted derivative 28a was found to be the most selective CYP11B2 inhibitor (IC(50) = 27 nM) in this series, showing a 120-fold selectivity for CYP11B1 (IC(50) = 3179 nM). Molecular modeling, i.e., examination of the electronic and steric features of selected compounds and homology modeling and docking, was used to understand the structure-activity/-selectivity relationships.

Recently we proposed inhibition of aldosterone synthase (CYP11B2) as a novel strategy for the treatment of congestive heart failure and myocardial fibrosis. In this study the synthesis and biological evaluation of heteroaryl-substituted naphthalenes and quinolines (1-31) is described. Key step for the preparation of the compounds was a Suzuki cross-coupling. Activity of the compounds was determined in vitro using human CYP11B2 and selectivity was evaluated toward the human steroidogenic enzymes CYP11B1, CYP19, and CYP17. A large number of highly active and selective inhibitors of CYP11B2 was identified. The most active inhibitor was the 6-cyano compound 8 (IC50 = 3 nM) showing a competitive type of inhibition (K(i) value = 1.9 nM). The 6-ethoxy derivative 5 was found to be the most selective CYP11B2 inhibitor (IC50 = 12 nM; K(i) value = 8 nM; CYP11B1 IC50 = 5419 nM; selectivity factor = 451), showing no inhibition of human CYP3A4 (50 nM) and CYP2D6 (20 nM). Docking and molecular dynamics studies using our homology modeled CYP11B2 structure with selected compounds were performed. Caco-2 cell experiments revealed a large number of medium and highly permeable compounds and metabolic studies with 2 using rat liver microsomes showed sufficient stability.