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Modification of some 8-benzylidene-5,6,7,8-tetrahydroquinolines, which have good antiulcer activity, led to three distinct classes of compounds with good in vivo antiinflammatory activity. Initial efforts led to a series of alkenes derived from 5,6,7,8-tetrahydroquinolines substituted at the 8-position. A second approach concentrated on replacing the CH linkage of these 8-benzylidene-substituted compounds with other spacer groups and increasing the size of the cycloalkyl ring from a six- to seven-membered ring, which provided 6,7,8,9-tetrahydro-5H-cyclohepta[b]pyridine analogues. Finally, the substituent was switched from the cycloalkyl ring to the 2-position of the pyridine ring. Variation of the 2-substituent was also examined. Optimal antiinflammatory activity after oral administration was found in both the rat carrageenan paw edema and rat developing adjuvant arthritis models with 2-substituted 6,7,8,9-tetrahydro-5H-cyclohepta[b]pyridines, and of particular interest was 27 (WY-28342).

WY-47,288 (2-[(1-naphthalenyloxy)methyl]quinoline) demonstrated topical antiinflammatory activity in several animal models of skin inflammation. Application of WY-47,288 to mouse ear surfaces inhibited arachidonic acid (ED50 = 0.3 mg/ear) and tetradecanoylphorbol acetate (TPA)-induced inflammation (40% at 1 mg/ear). Administration of WY-47,288 (1 mg/ear) at 30 min and 5 h after TPA reduced ear edema and epidermal proliferation by 50%. WY-47,288 also inhibited oxazolone-induced contact hypersensitivity in mouse ears (ED50 = 0.4 mg/ear) and UVB-induced guinea pig skin erythema (ED50 approximately 0.25 mg/spot). These antiinflammatory effects may be due to inhibition of 5-lipoxygenase (5-LO) and cyclooxygenase (CO) since the synthesis of 5-LO and CO products by rat neutrophils and mouse macrophages was dose-dependently reduced by WY-47,288. By contrast, WY-47,288 demonstrated no appreciable inhibition of 12-LO (rabbit platelet), 15-LO (soybean) or phospholipase A2 (human platelet). Furthermore, no systemic adverse effects were observed after topical, parenteral or oral administration of WY-47,288, suggesting that WY-47,288 is a safe topical 5-LO/CO inhibitor for treating skin inflammation.

The uxazole, oxaprozin has a spectrum of activity in various in vivo and in vitro, chronic and acute inflammatory models in 3 species indicating that it belongs to the general class of non-steruidal anti-inflammatory agents. Possible advantageous features of oxaprozin over existing nonsteroidal anti-inflammatory agents include relative safety, minimal irritant properties on the gastrointestinal tract, long half-life, and urieosurie properties.

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