Improvement of Techniques of Synthesis of Finasteride

The document discussed the improved synthesis techniques for Finasteride, a drug used to treat BPH by inhibiting 5α-reductase and reducing DHT levels. The synthesis started with zaixitongsuan, which reacted with thionyl chloride and t-butylamine to form 17β-carboxamide, followed by several chemical processes to produce the target compound. The new method avoided using expensive and toxic reagents, making it more suitable for large-scale production by replacing ammonia with NH4OAc, thus reducing equipment requirements and erosion.