Synthesis, Structure-Activity Relationships, and Pharmacological Evaluation of Pyrrolo[3,2,1-ij]quinoline Derivatives: Potent Histamine and Platelet Activating Factor Antagonism and 5-Lipoxygenase Inhibitory Properties. Potential Therapeutic Application in Asthma

• Published in: Journal of medicinal chemistry 1995-02, Vol.38 (4), p.669-685
• Main Authors: Paris, Dominique, Cottin, Michel, Demonchaux, Patrice, Augert, Guy, Dupassieux, Pierre, Lenoir, Patrick, Peck, Michael J, Jasserand, Daniel
• Format: Article
• Language: English
• Subjects: Animals; Asthma - drug therapy; Biological and medical sciences; Female; Guinea Pigs; Histamine and antagonists. Allergy; Histamine Antagonists - chemistry; Histamine Antagonists - pharmacology; Histamine Antagonists - therapeutic use; In Vitro Techniques; Lipoxygenase Inhibitors; Male; Medical sciences; Pharmacology. Drug treatments; Platelet Activating Factor - antagonists & inhibitors; Platelet Aggregation Inhibitors - pharmacology; Quinolines - chemistry; Quinolines - pharmacology; Quinolines - therapeutic use; Rabbits; Rats; Rats, Sprague-Dawley; Respiratory Function Tests; Skin Tests; Structure-Activity Relationship
• ISSN: 0022-2623; 1520-4804
• DOI: 10.1021/jm00004a013

A series of pyrrolo[3,2,1-ij]quinoline derivatives was synthesized and evaluated for their in vitro and in vivo activities against histamine, platelet activating factor (PAF), and leukotrienes which are recognized to be of importance in asthma. The structure-activity relationship studies have shown that the optimum moiety on the 1-position of the pyrroloquinoline nucleus is a 2-[4-(4-methyl-2-pyridinyl)-1-piperazinyl]ethyl chain in conjunction with a methyl group on the 2-position for potent antagonism of both histamine and PAF. The introduction of substituents on the 8- and 4-positions was also investigated in order to increase the potency of 5-lipoxygenase inhibition while retaining or improving the activities against histamine and PAF. This series is exemplified by 4-n-butyl-5,6-dihydro-8-hydroxy-2-methyl-1- [2-[4-(4-methyl-2-pyridinyl)-1-piperazinyl]ethyl]-4H-pyrrolo[3,2,1- ij]quinoline (24, KC 11404) which was found to be active against all three of the selected mediators. Compound 24 was found to be orally active in guinea pig models against the histaminic phase of antigen-induced bronchospasm and PAF-induced bronchoconstriction (ED50 = 1.9 and 2.1 mumol/kg, respectively). When tested against the leukotriene-dependent phase of the antigen-induced bronchoconstriction, compound 24 showed the same potency as zileuton.