Abstract: An acetamide derivative having the general formula (I): ##STR1## or a pharmacologically acceptable salt thereof; a synthetic intermediate of the above-mentioned acetamide derivative; a treating agent for peptic ulcer and for gastritis which comprises the above-mentioned compound having the general formula (I) as an effective ingredient, and a process for treating peptic ulcer and gastritis using the above-mentioned compound having the general formula (I), are disclosed.

Abstract: An acetamide derivative having the general formula (I): ##STR1## or a pharmacologically acceptable salt thereof; a synthetic intermediate of the above-mentioned acetamide derivative; a treating agent for peptic ulcer and for gastritis which comprises the above-mentioned compound having the general formula (I) as an effective ingredient, and a process for treating peptic ulcer and gastritis using the above-mentioned compound having the general formula (I), are disclosed.

Abstract: A bisphosphonic acid derivative of the formula (I) or a pharmaceutically acceptable salt thereof: ##STR1## wherein A is ##STR2## each of R.sup.3 and R.sup.4, which may be the same or different, is (i) a hydrogen atom, (ii) a C.sub.1-6 alkyl group, a C.sub.2-6 alkenyl group, a C.sub.2-6 alkynyl group, a C.sub.1-6 alkyl-carbonyl group, a C.sub.2-6 alkenyl-carbonyl group, a C.sub.2-6 alkynyl-carbonyl group R.sup.5 and R.sup.6, which may be the same or different, is a hydrogen atom, a hydroxyl group, a halogen atom, a cyano group, a carbamoyl group, an aralkyl group, a substituted or unsubstituted phenyl group, a substituted or unsubstituted amino group, a C.sub.1-6 alkyl group, a C.sub.2-6 alkenyl group, a C.sub.2-6 alkynyl group;each of m and n is 0 or a positive integer, provided that (m+n) is from 2 to 5; andR is a hydrogen atom, a C.sub.1-8 alkyl group or a C.sub.7-15 aralkyl group.

Abstract: A [2-hydroxy-3-(4-phenylpiperazinyl)propoxy]benzofuran derivative having the formula (I): ##STR1## wherein X is acetyl, carbamoyl, cyano, a lower alkoxycarbonyl, carboxyl or 1-hydroxyethyl group, R is hydrogen atom, a lower alkoxy group, a lower alkyl group or a halogen atom; R is attached to an arbitrary position of ortho-position, meta-position and para-position to N-phenyl group, and a group having the formula: ##STR2## is attached to an arbitrary position of 4, 5, 6 and 7 positions to benzofuran ring or the salt thereof, a process for preparing the same and an antihypertensive agent containing the same as an effective component. The benzofuran derivative has a strong .alpha.-adrenergic blockade effect and calcium antagonistic effect with a more decreased side-effect.