Synthesis, Antioxidant, and Anti-inflammatory Activity of Morpholine Mannich base of AMACs ((2E, 6E)-2-((4-hydroxy-3- [morpholin-4-yl-)methyl]phenyl)methylidene)-6-(phenylmethylidene) cyclohexan-1-one) and Its Analogs

A series of asymmetrical mono-carbonyl analogs of curcumin (AMACs) containing morpholine Mannich base ((2E, 6E)-2-((4-hydroxy-3-[morpholin-4-yl-)methyl]phenyl)methylidene)-6-(phenylmethylidene)cyclohexan- 1-one) was synthesized. The title compounds and the parent compounds were evaluated for antioxidant and antiinflammatory activity using 2,2-diphenyl-2-picrylhydrazyl (DPPH) free radical-scavenger method and protein denaturation method, respectively. Among the tested compounds, only compound 3d showed potent antioxidant activity which was comparable to cyclovalone. All the AMACs exhibited lower anti-inflammatory activity than that of cyclovalone. However, compounds 4c and 4d exhibited a potent anti-inflammatory activity which was almost comparable to cyclovalone and the standard diclofenac sodium.