SYNTHESIS AND PHARMACOLOGICAL PROPERTIES OF )-(2-ETHYL-2,3-DIHYDRO-2-SILAINDEN-2-YL)IMIDAZOLE, A SILICON ANALOG OF ATIPAMEZOLE

5)-(2-Ethyl-2,3-dihydro-2-silainden-2-yl)imidazole 2a, )-(2-methyl-2,3 -dihydro-2-silainden-2-yl)imidazole 2b and yl-2,3-dihydro-2-silainden- 2-yl)-2-methylimidazole 2c, C2 silicon analogues of the commercially a vailable alpha(2)-adrenergic receptor antagonist atipamezole 1, were p repared and their pharmacological properties were evaluated. The resul ts show that 2a retained significant affinity for the receptors, and t he in vivo pharmacokinetic properties of 2a were comparable to those o f 1.