In vivo assessment of newly synthesized achiral copper(II) and zinc(II) complexes of a benzimidazole derived scaffold as a potential analgesic, antipyretic and anti-inflammatory

Two new complexes of copper(II), [CuL2], and zinc(II), [ZnL2], with a tridentate -ONN' -Schiff base ligand (L), a bioactive scaffold derived from 2-aminobenzimidazole and 2-hydroxy-3-methoxybenzaldehyde, were synthesized and characterized using various spectroscopic techniques, viz, IR, H-1 and C-13 NMR, EPR, HRMS, and elemental analysis and purity analysis using UPLC studies. Both the complexes are non-electrolytic by nature. The newly synthesized compounds were screened for acetic acid-induced analgesic and yeast-induced antipyretic activities in mice and carrageenan-induced paw edema in rats (anti-inflammatory). The results showed that the [CuL2] compound (at 100 mg kg(-1) b.w) possessed potent anti-inflammatory activity whereas [ZnL2] (at 50 mg kg(-1) and 100 mg kg(-1) b.w) exhibited significant analgesic activity when compared with standard drugs. Both the complexes have apparently moderate and nearly akin antipyretic activity.