Method for acylating 21 site of steroid raw material medicine

The invention relates to the technical field of medicine synthesis, in particular to a steroid raw material medicine 21-site acylation method which comprises the following steps: under the action of a catalyst, performing acylation reaction on a steroid raw material medicine and an acylation reagent in an organic solvent to obtain a steroid raw material medicine 21-site acylate; the catalyst is alkali carbonate; the acylation reagent is any one or two of acetic anhydride and propionic anhydride; the organic solvent is any one or two of acetone and tetrahydrofuran. According to the invention, acetone or tetrahydrofuran which does not contain ammonia nitrogen is adopted to replace high-toxicity and high-ammonia-nitrogen pyridine, dimethylformamide, dimethyl sulfoxide and other solvents, so that the production of high-ammonia-nitrogen wastewater is avoided in the whole synthesis process, the environmental pollution is reduced, and the harm to an operator is reduced. In addition, the solvent acetone or tetrahydro