METHOD FOR PURIFYING ETHYNYLTHYMIDINE COMPOUND

摘要

Disclosed is a method for purifying 2',3'-didehydro-3'-deoxy-4'-ethynylthymidine or a base salt thereof, which is characterized in that a crystal of 2',3'-didehydro-3'-deoxy-4'-ethynylthymidine or a base salt thereof is deposited by bringing a solution containing a base salt of 2',3'-didehydro-3'-deoxy-4'-ethynylthymidine and a base salt of a diastereomer of 2',3'-didehydro-3'-deoxy-4'-ethynylthymidine into contact with a solvent in which base salts of 2',3'-didehydro-3'-deoxy-4'-ethynylthymidine are poorly soluble. The method can efficiently and commercially advantageously purify 2',3'-didehydro-3'-deoxy-4'-ethynylthymidine or a base salt thereof, which is useful as a pharmaceutical product.