Abstract:
Tilmicosin is a semi-synthetic macrolide antibiotics specially used in animal, which first developed by LiLai company and has a increasing sale at home recently. We use Tylosin phosphate as the primal material, through hydrolyzing, then react with the 3,5- methyl piperidine to synthesize Tilmicosin.
Through this experiment, we find the optimum reaction conditions, and thus increasing the output. The first step of the reaction is acid hydrolyzing, adding proper sulfuric acid to regulate the pH between 1.4-1.7, reacting 1 hour, Temperature 35℃,and the yields is above 98% after hydrolysis. The suitable molar ratio of the Desmycosin and 3,5-Methyl Piperidine and Acid is 1∶1.1∶1.5, the reacting time is 2 hour ,and the suitable reacting tempeture is 70℃.Eventually we get the product in 89% rate in this condition.
In this experiment, we found that the disposing of impurities in the after-treatment process is also very important. Activated Carbon Decolorizing is a direct factor on the precipitation of product; We also discovered that the concentration of NaOH can affect the shape of the crystal in maintaining granular crystal process.
Keywords: Phosphoric acid Tylosin, Tilmicosin, Macrocyclic lactone, Hydrolysis, PLC.