Design and synthesis of ibuprofen-quinoline conjugates as potential anti-inflammatory and analgesic drug candidates

[Display omitted] •A set of ibuprofen conjugates was designed and synthesized.•Some conjugates show promising anti-inflammatory and analgesic properties.•Some of the potential conjugates show selectivity towards COX-2.•Most of the conjugates significantly reduce the release and production of nitric oxide in the LPS-stimulated macrophages.•The developed QSAR model could be a useful tool for new drug development.•Potential conjugates could be further explored for the development of potential antiviral drug candidates. A new set of ibuprofen-quinoline conjugates comprising quinolinyl heterocycle and ibuprofen moieties linked by an alkyl chain were synthesized in good yields utilizing an optimized reaction procedure in a molecular hybridization approach to overcome the drawbacks of the current non-steroidal anti-inflammatory drugs. The synthesized conjugates were screened for their anti-inflammatory, and ulcerogenic properties. Several conjugates were found to have significant anti-inflammatory properties in the carrageenan-induced rat paw edema test without showing any ulcerogenic liability. In addition, most conjugates showed promising peripheral analgesic activity in the acetic acid-induced writhing test as well as central analgesic properties in the in vivo hot plate test. The most promising conjugates were the unsubstituted and 6-substituted fluoro- and chloro-derivatives of 2-(trifluoromethyl)quinoline linked to ibuprofen by a propyl chain. Their anti-inflammatory activity was evaluated against LPS-stimulated inflammatory reactions in RAW264.7 mouse macrophages. In this regard, it was found that most of the conjugates were able to significantly reduce the release and production of nitric oxide in the LPS-stimulated macrophages. The secretion and expression of the pro-inflammatory cytokines IL-6, TNF-α, and inducible nitric oxide synthase (iNOS) were also significantly suppressed.