Disclosed are indole derivatives of formula (I) represent H or -CH2CH2R; R represents pyridyl or substituted amino of NR1R2; R1 represents H or C1-C6 alkyl; R2 represents 2-(3-indolyl)ethyl or aralkyl; or R1 and R2 together with the nitrogen atom to which they are attached may form an N-containing 5 to 6 membered hetero ring, an N, O-containing hetero ring, which hetero ring may be fused with benzene; n is an integer of 4 to 8; with the proviso that X and Y both do not represent H or piperizinoethyl when n is 4, or pharmaceuticaly acceptable acid addition salts thereof. They are useful as an antiulcer agent.
