Refining method for high-purity bepotastine besilate

[0057] The refining method of high-purity bepotastine bepotastine in the present embodiment comprises the following steps:

[0058] 1. Add 20 g of crude bepotastine besilate to 200 ml of acetonitrile, heat to 80°C, stir to dissolve and filter, cool the filtrate to 25-30°C, stir and crystallize for 6 hours, filter, and dry the filter cake at 60°C under reduced pressure After 4 hours, 18.3 g of the primary refined product was obtained, with a yield of 91.5% and a purity of 99.89%.

[0059] 2. Add 18g of the primary refined product to 90ml of water, heat to 30-40°C, stir to dissolve, cool to -1-5°C, stir and crystallize for 6h, filter, and dry the filter cake at 40°C for 12h under reduced pressure to obtain benzenesulfonate Bepotastine pure product 16.3g, yield 90.6%, purity 99.99%.

[0061] 1. Add 20 g of crude bepotastine besilate to 300 ml of acetonitrile, heat to 60°C, stir to dissolve and filter, cool the filtrate to 10-20°C, stir and crystallize for 8 hours, filter, and dry the filter cake at 50°C under reduced pressure After 5 hours, 18.4 g of the primary refined product was obtained, with a yield of 92% and a purity of 99.90%.

[0062] 2. Add 18g of the primary refined product to 35ml of water, heat to 70°C, stir to dissolve, cool down to -1-5°C, stir and crystallize for 4h, filter, and dry the filter cake at 50°C for 10h under reduced pressure to obtain bezulbeta The pure product of Sting is 16.4g, the yield is 91.1%, and the purity is 99.96%.

[0064] 1. Add 100g of crude bepotastine besilate to 1000ml of acetonitrile, heat to 90°C, stir to dissolve and filter, cool the filtrate to 20-30°C, stir and crystallize for 6h, filter, and dry the filter cake at 70°C under reduced pressure After 4 hours, 92.8 g of the primary refined product was obtained, with a yield of 92.8% and a purity of 99.88%.

[0065] 2. Add 92g of the primary refined product to 270ml of water, heat to 50°C, stir to dissolve, cool to -1-5°C, stir and crystallize for 5h, filter, and dry the filter cake at 55°C for 10h under reduced pressure to obtain besylate The pure product of Sting is 84.8g, the yield is 92.2%, and the purity is 99.97%.