Pharmaceutically useful carbostyril derivatives

A carbostyril derivative represented by the formula, ##STR38## wherein R.sup.1 is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, an alkynyl group having 2 to 4 carbon atoms or a phenyl alkyl group having an alkylene group having 1 to 4 carbon atoms;

• R.sup.2 is an alkyl group having 1 to 4 carbon atoms or a phenyl group;
• R.sup.3 is a hydrogen atom, a hydroxy group, an alkyl group having 1 to 4 carbon atoms, an alkanoyloxy group having 1 to 4 carbon atoms or a 3,4,5-trimethoxybenzoyloxy group;
• R.sup.4 is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms;
• R.sup.5 is a phenyl group which may be substituted by 1 to 3 identical or different groups selected from the group consisting of a halogen atom, an alkyl group having 1 to 4 carbon atoms and an alkoxy group having 1 to 4 carbon atoms;
• X is a halogen atom;
• n is 0 or an integer of 1 to 2;
• Q is an integer of 2, l and m are respectively 0 or an integer of 1 to 6, but the sum of l and m should not exceed 6;
• the carbon-carbon bond at the 3- and 4-positions in the carbostyril skeleton is a single or double bond;
• the substituted position of the side chain of ##STR39## is any one of the 5-, 6-, 7- or 8-positions;
• or an acid addition salt thereof.

A method for producing an antihistaminic effect in a mammal comprising the step of administering to the mammal for producing said antihistaminic effect a pharmaceutical composition containing a suitable amount of a carbostyril derivative represented by the formula, ##STR44## wherein R.sup.1 is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, an alkynyl group having 2 to 4 carbon atoms or a phenyl alkyl group having an alkylene group having 1 to 4 carbon atoms;

• R.sup.2 is a hydrogen atom, an alkyl group having 1 to 4 carbon atoms or a phenyl group;
• R.sup.3 is a hydrogen atom, a hydroxy group, an alkyl group having 1 to 4 carbon atoms, an alkanoyloxy group having 1 to 4 carbon atoms or a 3,4,5-trimethoxybenzoyloxy group;
• R.sup.4 is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms;
• R.sup.5 is a cycloalkyl group having 3 to 8 carbon atoms, a phenyl group which may be substituted by 1 to 3 identical or different groups selected from the group consisting of a halogen atom, an alkyl group having 1 to 4 carbon atoms and an alkoxy group having 1 to 4 carbon atoms, a substituted alkyl group having 1 to 4 carbon atoms, having one hydroxy group, phenyl group or alkanoyloxy group having 1 to 4 carbon atoms as the substituent, an alkanoyl group having 1 to 4 carbon atoms or a benzoyl group;
• X is a halogen atom;
• n is 0 or an integer of 1 or 2;
• Q is an integer of 2;
• l and m are respectively 0 or an integer of 1 to 6, but the sum of l and m should not exceed 6;
• the carbon-carbon bond at the 3- and 4-positions in the carbostyril skeleton is a single or double bond;
• the substituted position of the side chain of ##STR45## is any one of the 4-, 5-, 6-, 7-, or 8-positions;
• or an acid addition salt thereof, with the proviso that when said side chain is substituted at the 4-position and said carbon-carbon bond at the 3- and 4-positions is a double bond, then R.sup.2 does not exist.

A carbostyril derivative represented by the formula, ##STR50## wherein R.sup.1 is a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 4 carbon atoms, an alkynyl group having 2 to 4 carbon atoms or a phenyl alkyl group having an alkylene group having 1 to 4 carbon atoms;

• R.sup.2 is a hydrogen atom, a C.sub.1 -C.sub.4 alkyl group;
• R.sup.3 is a hydrogen atom, a hydroxy group, an alkyl group having 1 to 4 carbon atoms, an alkanoyloxy group having 1 to 4 carbon atoms or a 3,4,5-trimethoxybenzoyloxy group;
• R.sup.4 is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms;
• R.sup.5 is a cycloalkyl group having 3 to 8 carbon atoms, a substituted alkyl group having 1 to 4 carbon atoms, having one phenyl group as the substituent, an alkanoyl group having 1 to 4 carbon atoms or a benzoyl group;
• X is a halogen atom;
• n is 0 or an integer of 1 or 2;
• Q is an integer of 2;
• l and m are respectively 0 or an integer of 1 to 6, but the sum of l and m should not exceed 6;
• the carbon-carbon bond at the 3- and 4-positions in the carbostyril skeleton is a single or double bond;
• the substituted position of the side chain of ##STR51## is any one of the 4-, 5-, 6-, 7-, or 8-positions;
• or an acid addition salt thereof, with the proviso that when said side chain is substituted at the 4-position and said carbon-carbon bond at the 3- and 4-positions is a double bond, then R.sup.2 does not exist.