Preparation and purification method of neostigmine methylsulfate

The invention relates to a preparation and purification method of neostigmine methylsulfate. The preparation method comprises the following steps of: dissolving a neostigmine methylsulfate crude product in an organic solvent 2, crystallizing at low temperature, filtering and drying to obtain a neostigmine methylsulfate fine product. The method provided by the invention can effectively reduce the ignition residue and sulfate radical content in the neostigmine methylsulfate product, meets the requirements of pharmacopeia, and ensures the drug quality and medication safety. 本发明涉及一种甲硫酸新斯的明的制备和纯化方法。所述制备方法包括如下步骤：所述纯化方法包括将甲硫酸新斯的明粗品经有机溶剂2溶解，低温析晶，过滤、干燥后得到甲硫酸新斯的明精品。所提供方法可有效降低甲硫酸新斯的明产品中炽灼残渣和硫酸根含量，符合药典要求，保证药品质量及用药安全。