A series of 5-aminoalkylpyrrolo [3, 2-c] azepine derivatives was synthesized and their serotonin 2 (5-HT 2) receptor antagonist and antiplatelet aggregation activities were evaluated. 5-HT 2 receptor antagonist activity was largely determined by the nature of the substituent at the 8-position as well as aminoalkyl group at the 5-position of the pyrrolo [3, 2- c] azepine ring. Compound 18a, 5-[3-] 4-(4-fluorophenyl) piperazin-1-yl] propyl]-8-hydroxy ...