Lipophilic 4-Isoxazolyl-1,4-dihydropyridines:  Synthesis and Structure−Activity Relationships

A series of 4-isoxazolyl-1,4-dihydropyridines bearing lipophilic side chains at the C-5 position of the isoxazole ring have been prepared. The calcium channel antagonistic activity of these compounds has been evaluated. A hypothetical model for binding of these compounds in the calcium channel is proposed, and the validity of this model is evaluated based on the SAR of this series of calcium binding, especially for the two most active derivatives, 1a,g. The solid-state structure for the most active compound, 1a, has also been determined, and its important features are reported.