|Title:|| 7,6 Dioxo-4H,6H-pyrano[3,2-g]quinoline dicarboxylic acids and anti-allergic use thereof|
|Abstract:||There are described compounds of formula I ##STR1## in which an adjacent pair of R.sub.5, R.sub.6, R.sub.7 and R.sub.8 form a chain --COCH.dbd.CE--O--, and the remainder of R.sub.5, R.sub.6, R.sub.7 and R.sub.8, which may be the same or different, each represent hydrogen, hydroxy, alkyl, halogen, alkenyl, alkoxy, or --NR.sub.1 R.sub.2 in which R.sub.1 and R.sub.2, which are the same or different, are each hydrogen or alkyl, Rg is hydrogen, alkyl, alkenyl or phenyl-alkyl, and E is --COOH, a 5-tetrazolyl group or an (N-tetrazol-5-yl) carboxamido group, and pharmaceutically acceptable derivatives thereof. There are also described processes for making the compounds and pharmaceutical, e.g. anti-allergic, compositions containing the compounds.|
|Inventor(s):|| Cairns; Hugh (Loughborough, GB2), Cox; David (Loughborough, GB2) |
|Assignee:|| Fisons Limited (GB2) |
1. A compound having the formula ##STR16## in which R.sub.6 and R.sub.7 form a chain --COCH.dbd.C(COOH)--O--, R.sub.5 and R.sub.8, which may be the same or different, are sterically
compatible substituents selected from hydrogen and alkyl having up to 8 carbon atoms, and
R.sub.g is hydrogen or alkyl having up to 8 carbon atoms,
and pharmaceutically acceptable salts and ethyl esters thereof.
2. A compound according to claim 1, wherein each of R.sub.5, R.sub.8 and R.sub.g, when they are alkyl, contain up to 4 carbon atoms.
3. A compound according to claim 1, wherein the --COCH.dbd.C(COOH)--O-- chain is bonded with the --O-- end thereof in position R.sub.7.
4. A compound according to claim 1, wherein R.sub.5 and R.sub.8 are selected from hydrogen and propyl.
5. A compound according to claim 1, wherein R.sub.g is ethyl.
6. 4,6-Dioxo-1-ethyl-10-propyl-4H,6H-pyrano[3,2-g]quinoline-2 ,8-dicarboxylic acid or a pharmaceutically acceptable salt thereof.
7. 4,6-Dioxo-10-propyl-4H,6H-pyrano[3,2-g]quinoline-2,8-dicarboxylic acid or a pharmaceutically acceptable salt thereof.
8. A pharmaceutical composition suitable for the treatment of a condition involving an antibody antigen reaction or a reflex pathway comprising an effective amount of a compound according to claim 1 in combination with a pharmmaceutically
acceptable adjuvant, diluent or carrier.
9. A composition according to claim 8 comprising less than 80% by weight of active ingredient.
10. A composition comprising from 0.01 mg to 50 mg of a compound according to claim 1, as active ingredient, in unit dosage form.
11. A method of treatment of a condition involving an antibody antigen reaction or a reflex pathway, which comprises administering an effective amount of a compound according to claim 1 to an animal suffering from such a condition.