Neuroprotection by new ligustrazine-cinnamon acid derivatives on CoCl-induced apoptosis in differentiated PC12 cells.

A new series of ligustrazine-cinnamon acid derivatives had been designed and synthesized as potential neuro-protective agents. Among the derivatives, 3a exhibited the promising neuroprotective activity (EC = 3.68 μM). Moreover, with the deep research of the drug pathway, it (the further mechanism researches) suggested compound 3a could inhibit the apoptosis of injured PC12 cells via blocking the mitochondria apoptosis pathway including up-regulation the ratio of Bcl-2/Bax, down-regulation the expression of cytochrome-c (Cyt-c) and inhibition of the activity of caspase-9 and -3. In addition, the structure-activity relationships (SARs) of novel compounds were also discussed.