Scheme 1From: Ligustrazinyl amides: a novel class of ligustrazine-phenolic acid derivatives with neuroprotective effects Synthetic routes to ligustrazine intermediate L. Reagents and Conditions: (i) CCl4, NBS, hv, reflux, 2 h, 65%; (ii) CH3CN, phthalimide potassium, reflux, 2 h, 64%; (iii) CH3CH2OH, N2H4 · H2O, reflux, 5 h, 88%.Back to article page