The invention discloses a
cholinesterase inhibitor preparation method, and belongs to the technical field of separation and purification of natural medicines. The preparation method comprises: soakinga macroporous cation exchange resin by using an acid solution, completely removing the acid liquid, rinsing with water, soaking with an alkali liquid, rinsing with water, soaking with an acid liquid,rinsing with deionized water, and replacing with lower
alcohol; adding
glycerol phosphate to the lower
alcohol, adding an alkali, carrying out a reaction, carrying out suction
filtration, washing with lower
alcohol, adjusting the pH value to a weakly alkaline state, carrying out pressure reducing concentrating, cooling, transferring into a
separatory funnel, standing, and separating to obtain a lower layer lower alcohol phase; loading
glycerol phosphate and a
phenol formaldehyde resin onto a column, loading the alcoholysis mixing liquid onto the column, adsorbing, washing the resin with loweralcohol to remove impurities, and eluting the resin with pure water; and decolorizing with a decolorizing agent, and carrying out pressure reducing concentrating to obtain the finished product. According to the present invention, the process steps are short, the requirements of industrial production are met, the resources are saved, the cost is reduced, the total yield of the finished products is65.47-86.08%, the external standard content is over 99%, and the optical purity is 99%.