4-Quinolinones having antihypertensive activity

Quinolone compounds of the general formula ##STR13## wherein n is 0, 1 or 2;

• R.sub.1 is C.sub.1-4 alkyl, R.sub.2 is C.sub.1-4 alkyl and
• (a) R.sub.5 is hydrogen and R.sub.4 is 6-lower alkoxy, 8-lower alkoxy, 5-halo or 6-halo;
• (b) R.sub.4 is hydrogen and R.sub.5 is halo, lower alkyl, lower alkoxy, trifluoromethyl or lower alkylthio;
• or
• (c) R.sub.5 is halo, lower alkoxy or lower alkyl and R.sub.4 is 6-lower alkyl, 6-lower alkoxy or 6-halo of a different value from R.sub.5,
• with the proviso that, when R.sub.4 is hydrogen, R.sub.5 is 7-methyl and R.sub.1 is ethyl, R.sub.2 contains more than one carbon atom.

Therapeutic compositions suitable for antihypertensive use which comprise as an active ingredient an antihypertensive amount of a quinolone compound of the general formula ##STR14## wherein n is 0, 1 or 2;

• R.sub.1 is lower alkyl optionally substituted by hydroxy or C.sub.1-4 alkoxycarbonyl;
• allyl;
• propynyl or phenyl-lower alkyl in which the phenyl ring is optionally substituted by 1 or 2 C.sub.1-4 alkoxy groups;
• R.sub.2 is C.sub.1-4 alkyl with the proviso that when n is 0, R.sub.2 is methyl;
• and R.sub.3, R.sub.4 and R.sub.5, which may be the same or different, are hydrogen, lower alkyl, lower alkoxy, lower alkanoyl, halo, trifluoromethyl or lower alkylthio, together with a pharmaceutically acceptable carrier.

A method of treating hypertension in a hypertensive warm blooded animal which comprises administering to the hypertensive animal a therapeutically effective amount of a quinolone compound of the formula ##STR17## wherein n is 0, 1, or 2;

• R.sub.1 is lower alkyl optionally substituted by hydroxy or C.sub.1-4 alkoxycarbonyl;
• allyl;
• propynyl or phenyl-lower alkyl in which the phenyl ring is optionally substituted by 1 or 2 C.sub.1-4 alkoxy groups;
• R.sub.2 is C.sub.1-4 alkyl with the proviso that when n is 0, R.sub.2 is methyl;
• and R.sub.3, R.sub.4, and R.sub.5, which may be the same or different, are hydrogen, lower alkyl, lower alkoxy, lower alkanoyl, halo, trifluoromethyl, or lower alkylthio.