Quinolone derivatives as dopamine D.sub.4 ligands

Drug – bio-affecting and body treating compositions – Designated organic active ingredient containing – Having -c- – wherein x is chalcogen – bonded directly to...

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546157, 544363, 514253, A61K 3147, C07D215227, C07D21512

Patent

active

056079460

DESCRIPTION:

BRIEF SUMMARY
This application is a 371 of PCT/GB 94/00385, filed 25 Feb. 1994.
This invention relates to the use of a particular class of heteroaromatic compounds. More particularly, the invention is concerned with the use of substituted 2(1H)-quinolone derivatives which are antagonists of dopamine receptor subtypes within the brain and are therefore of benefit in the treatment and/or prevention of psychotic disorders such as schizophrenia.
The "dopamine hypothesis" of schizophrenia predicts an increased activity of dopamine neurotransmission in the disease. The hypothesis is supported by early observations that drugs, such as amphetamine, with dopamine agonist or dopamine-releasing properties are capable of eliciting a psychosis indistinguishable from acute paranoid schizophrenia.
Schizophrenia is a disorder which is conventionally treated with drugs known as neuroleptics. In the majority of cases, the symptoms of schizophrenia can be treated successfully with so-called "classical" neuroleptic agents such as haloperidol. Classical neuroleptics generally are antagonists at dopamine D.sub.2 receptors. The fact that classical neuroleptic drugs have an action on dopamine receptors in the brain thus lends credence to the "dopamine hypothesis" of schizophrenia.
Molecular biological techniques have revealed the existence of several subtypes of the dopamine receptor. The dopamine D.sub.1 receptor subtype has been shown to occur in at least two discrete forms. Two forms of the D.sub.2 receptor subtype, and at least one form of the D.sub.3 receptor subtype, have also been discovered. More recently, the D.sub.4 (Van Tol et al., Nature (London), 1991, 350, 610) and D.sub.5 (Sunahara et al., Nature (London), 1991, 350, 614) receptor subtypes have been described.
Notwithstanding their beneficial antipsychotic effects, classical neuroleptic agents such as haloperidol are frequently responsible for eliciting acute extrapyramidal symptoms and neuroendocrine disturbances. These side-effects, which clearly detract from the clinical desirability of classical neuroleptics, are believed to be attributable to D.sub.2 receptor blockade in the striatal region of the brain. It is considered (Van Tol et al., supra) that compounds which can interact selectively with the dopamine D.sub.4 receptor subtype, whilst having a less-pronounced action at the D.sub.2 subtype, might be free from, or at any rate less prone to, the side-effects associated with classical neuroleptics, whilst at the same time maintaining a beneficial level of antipsychotic activity.
The compounds of use in the present invention, being antagonists of dopamine receptor subtypes within the brain, are accordingly of benefit in the treatment and/or prevention of psychotic disorders such as schizophrenia. Moreover, the compounds of use in the invention have a selective affinity for the dopamine D.sub.4 receptor subtype over other dopamine receptor subtypes, in particular the D.sub.2 subtype, and can therefore be expected to manifest fewer side-effects than those associated with classical neuroleptic drugs.
JP-A-64-63518 and HU-A-T/54348 variously describe certain 2(1H)-quinolone derivatives which are stated to have anti-arrhythmic activity. There is, however, no suggestion in either of these publications that the compounds described therein would be of any benefit in the treatment and/or prevention of psychotic disorders such as schizophrenia, still less that in doing so they might be expected to manifest fewer side-effects than those exhibited by classical neuroleptic agents.
The present invention accordingly provides the use of a compound of formula I, or a pharmaceutically acceptable salt thereof or a prodrug thereof: ##STR1## wherein R represents hydrogen or C.sub.1-6 alkyl; ##STR2## in which the broken line represents an optional chemical bond; R.sup.1 represents hydrogen, or an optionally substituted C.sub.1-6 alkyl, C.sub.1-6 alkoxy, C.sub.2-6 alkenyl, C.sub.2-6 alkynyl, aryl, aryl(C.sub.1-6)alkyl, aryl(C.sub.1-6)alkoxy, aryl(C.sub.2-6)alkenyl, aryl(C.sub.2-6)alkynyl, C.sub.3

REFERENCES:
patent: 3514459 (1970-05-01), Ritter
patent: 3799928 (1974-03-01), Sclager
patent: 5064837 (1991-11-01), McCombie
patent: 5318971 (1994-06-01), McCombie
Portlock, J Org Chem, vol. 38, No. 13, pp. 2351-2355, 1973.

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