New 1,3,4-oxadiazole/oxime hybrids: Design, synthesis, anti-inflammatory, COX inhibitory activities and ulcerogenic liability.

A series of new 1,3,4-oxadiazole/oxime hybrids were synthesized and designed as potent COX inhibitors. The prepared compounds were evaluated for their anti-inflammatory, antioxidant and ulcerogenic activities. The results indicated that the prepared compounds exhibited remarkable anti-inflammatory activity with (69.60-109.60% of indomethacin activity) after 4h. In vitro COX inhibitory assay showed that compounds 6d and 7h are potent COX inhibitors with IC50 of (1.10-0.94) and (2.30-5.00) µM on both COX-1 and COX-2 respectively. Compound 7h was found to inhibit both COXs non-competitively with Ki values of 73µM and 89µM. Most of the tested compounds showed ulcer-free stomachs compared to indomethacin.

Novel 1,3,4-oxadiazole/oxime hybrids: Synthesis, docking studies and investigation of anti-inflammatory, ulcerogenic liability and analgesic activities.

A novel group of 1,3,4-oxadaiazoles, a group known for their anti-inflammatory activity, is hybridized with nitric oxide (NO) releasing group, oxime, for its gastro-protective action and potential synergistic effect. The synthesized hybrids were evaluated for their anti-inflammatory, analgesic, antioxidant and ulcerogenic activities. Most of the tested compounds showed excellent anti-inflammatory activity with compound 8e being more active than indomethacin. They also showed moderate analgesic activity but no antioxidant one. The ability of the synthesized compounds to inhibit COX-1 and COX-2 is studied and the prepared compounds were able to inhibit both COXs non-selectively with IC50s of 0.75-70.50µM. Docking studies revealed the mode of interaction of the tested compounds into the empty pocket of the isozymes. All of the synthesized compounds interact with COXs active site with energy scores comparable to that of ibuprofen. All compounds showed a safer profile on the stomach tissue integrity compared to conventional NSAIDs. The designed strategy was applied to ibuprofen to introduce ibuprofen/oxadiazole/NO hybrid. The synthesized ibuprofen hybrid is a promising alternative to ibuprofen having similar anti-inflammatory activity but with safer GIT profile.