Study On Synthesis Of Finasteride

Finasteride,brand name of which is Proscar, is the achieve- ment of 15 years of research of MSD. It is a kind of 5α-2 reducing enzyme inhibitor and was applied to clinical experience in June 1992 after receiving validation in America. Its chemical name is N-tertbut- yl-3-oxo-4-aza-5α-androst-1-ene-17β-carboxamide.Finasteride belongs to the 4-azasteroid structure class of comp- ounds which can selectively and competively inhibit the activity of 5α- reducing enzyme. The course of testosterone(T) changing into dihydrotestosterone(DHT) needs the participation of this kind of nicotinamide adenine dinucleotide phosphate(NADPH) dependent enzyme. Finasteride can specially inhibit typeⅡisoenzyme of 5α-2 reducing enzyme, and the latter is mainly synthesized in parastata glandulosa. The inhibition of finasteride may cause serum DHT decreasing by 60%-80%, and prostatic DHT decreasing by 90% abo- ve. The serum prostate specific antigen(PSA) of BPH patients treat- ed with finasteride is obviously decreased, but the average ratio of thefree PSA with gross PSA is not affected. Finasteride may induce the contraction of parastata glandulosa by means of atrophy and...