Biologically active tetracyclic compounds and pharmaceutical compositions containing same

摘要

Novel and biologically active tetracyclic compounds are disclosed of the formula: <IMAGE> (I) or a pharmaceutically acceptable non-toxic salt thereof, wherein R1, R2, R3, and R4 are each hydrogen, hydroxy, C1-C6 alkyl, C1-C6 alkoxy, C1-C6 alkylthio, halogen, or trifluoromethyl; R5 is hydrogen or C1-C6 alkyl; and X is oxygen or methylene. Pharmaceutical compositions containing these compounds are disclosed to take advantage of CNS-inhibiting properties thereof, especially sedative and tranquillizing properties.