Monomethyl auristatin E crystal and preparation method thereof

The invention provides a monomethyl auristatin E crystal form A and a preparation method thereof, a pharmaceutical composition containing the crystal form A, and application of the crystal form A in preparation of pharmaceutical conjugates. The crystal form A is high in purity, good in stability, low in hygroscopicity and especially suitable for industrial application, and the defects that in the prior art, amorphous MMAE is low in purity, poor in stability and not suitable for storage, and when the amorphous MMAE is used for preparing conjugates, the requirement for reaction equipment is high, and operation is complex are overcome; and secondly, the preparation method of the MMAE crystal form A provided by the invention is simple to operate, the prepared crystal form is high in purity and uniform in particle size distribution, the production cost is reduced, and the preparation method is suitable for commercial production amplification. 本发明提供了一种一甲基澳瑞他汀E的晶型A及其制备方法，包含该晶型A的药物组合物，以及这些晶型A在制备药物偶联物中的应用。所述晶型A纯度高，稳定性