Synthesis and Anti-Inflammatory Evaluation of Novel C66 Analogs for the Treatment of LPS-Induced Acute Lung Injury.

We previously reported a symmetric monocarbonyl analog of curcumin (MACs), C66, which demonstrated potential anti-inflammatory activity and low toxicity. In continuation of our ongoing research, we designed and synthesized 34 asymmetric MACs based on C66 as a lead molecule. A majority of the C66 analogs effectively inhibited LPS induction of TNF-α and IL-6 expression. Additionally, a preliminary SAR was conducted. Furthermore, active compounds 4a11 and 4a16 were found to effectively reduce the W/D ratio in the lungs and the protein concentration in the bronchoalveolar lavage fluid (BALF). Meanwhile, a histopathological examination indicated that these two analogs significantly attenuate tissue injury in the lungs with LPS-induced ALI rats. 4a11 and 4a16 also inhibited mRNA expression of several inflammatory cytokines, including TNF-α, IL-6, IL-1β, COX-2, ICAM-1 and VCAM-1, in the Beas-2B cells after LPS challenge. Altogether, the data exhibit a series of new C66 analogs as promising anti-inflammatory agents for the treatment of LPS-induced ALI.