Pharmacological action:

Ligustrazine is a bioactive ingredient extracted from ligustrum chuanxiong, a widely used traditional Chinese medicine. It can inhibit platelet aggregation, enhance vasodilation, increase cerebral blood flow, and have neuroprotective effects. Ligustrazine injection has been widely used in the treatment of ischemic stroke, coronary heart disease, diabetic nephropathy and knee osteoarthritis in China. Ligustrazine has also been evaluated clinically for the treatment of pressure ulcers, as a salvage agent for patients with non-Hodgkin's lymphoma, and as a treatment for bronchial asthma and vertebrobasilar dysfunction.

Chemical properties:

white crystal or powder. It has the aroma of beef and pork fat when heated and fermented soy flavor. When diluted to 20mg/kg, it has the flavor of milk chocolate. Boiling point 190℃, melting point 84 ~ 86℃. Soluble in ethanol, most non-volatile oils and propylene glycol, slightly soluble in water. Natural products are found in guava, roast beef, cocoa, coffee, shrimp, etc.

Production method:

butanedione monooxime is formed by condensation of butanone and ethyl nitrite, and then methylmethylpyrazine is obtained by reduction and cyclization. The cyclic reaction products were distilled by steam, and the distillate was cooled, crystallized and filtered to obtain crude tetramethylpyrazine. Water recrystallization and activated carbon decolorization were used for refining. To prepare its hydrochloride, it can be dripped into acetone with an ethanol solution containing 15%-20% hydrogen chloride to form a salt.