(4RS)-1-(5-Cyclopropyl-1, 2, 4-oxadiazol-3-y1)-12, 12a-dihydroimidazo [1, 5-a] pyrrolo [2, 1- c] quinoxalin-lO (llH)-one (la), 5-benzoyl-3-(5-cyclopropyl-1, 2, 4-oxadiazol-3-yl)-4, 5- dihydroimidazo [1, 5-alquinoxaline (13b), and tert-butyl (4S)-12, 12a-dihydroimidazo [l, 5- alpyrrolo [2, 1-clquinoxaline-1-carboxylate (le), as well as other imidazo [1, 5-alquinoxaline amides and carbamates, represent a new series of compounds which bind with high ...