Stereochemical Requirements for the Mineralocorticoid Receptor Antagonist Activity of Dihydropyridines

A number of known 1,4-dihydropyridine CCBs were identified as having comparable potency to the steroidal MR antagonist eplerenone. Chiral resolution of mebudipine revealed that MR and CCB activity reside in opposite enantiomers. Small molecule X-ray crystal structures showed that the C4 stereochemistry of optimized selective MR analogues, e.g. 5, is consistent with MR-active mebudipine. Molecular modeling supports a binding pose consistent with that previously proposed for DHP diesters.