RESUMEN
A new series of 1,2,4-triazole-5-thione Mannich derivatives containing a naproxen moiety (1a-o) was designed and synthesized to create naproxen analogs, with the aim of developing novel anti-inflammatory/analgesic agents with improved safety profiles. Target compounds were synthesized using classical Mannich reaction (i.e. one-pot three component condensation reaction), by reacting triazole molecule (1), formaldehyde, and diverse secondary amines in ethanol. The synthesized compounds were investigated using FT-IR, 1H NMR, 13C NMR and mass spectroscopies, as well as elemental analysis. Compounds were then evaluated for their potential antinociceptive and anti-inflammatory activities using some validated invivo methods. Data obtained from acetic acid induced-writhing and carrageenan-induced paw edema tests revealed that all compounds induced peripherally-mediated antinociceptive activities, as well as notable anti-inflammatory effects. The results of hot-plate and tail-clip tests indicated that compounds 1a, 1b, 1c, 1d, 1g, and 1j have also centrally-mediated antinociceptive activities in addition to their peripherally-mediated effects. Molecular docking studies were performed to investigate the putative binding modes of the interactions between all compounds and COX-1/COX-2 enzymes using AutoDock Vina software. Docking of the compounds into the COX-2 active site produced binding interactions that are essential for COX-2 inhibitory activity. None of the compounds in the serial, except for 1m and 1j, induced significant gastrointestinal irritation. Overall, the results indicated that triazol Mannich bases bearing a naproxen moiety potentially represent a novel class of antinociceptive and anti-inflammatory agent with an improved gastric safety profile.
