Spiro dibenzosuberane derivatives.

摘要

The compounds of the present invention relates to spiro dibenzosuberane derivatives represented by the formula (I): wherein R<1> is hydrogen, alkyl, alkenyl, or aralkyl: R<2> is hydrogen or alkyl; R<3> and R<4> which are the same or different are hydrogen, alkyl, alkoxy, or halogen; m is 0 or 1; n is an integer of 1-4, or a pharmaceutically acceptable acid addition salt thereof, with antineurodegenerative activities and are non-compeptitive antagonist against NMDA receptor, whereby these are thought effective for the prevention or treatment of the ischemic encephalopathy and Alzheimer's disease.