| production method | β-naphthol may be etherified with methanol and subjected to catalytic hydrogenation and oxidation, 6-methoxynaphthalenone is formed, then (keto) is added with vinyl magnesium bromide and with 1-ethyl-2, 5-cyclopentanedione condensation and cyclization of 3-methoxy-18-methylestrene-1, 3,5(10),8,14-penten-17-one, then catalytically hydrogenates (14-position double bond) and reduces to obtain 17-hydroxy-3-methoxy-18-methyl-19-desmethylandrosterin-2, 5(10) Diene, finally by biological oxidation (17-hydroxyl), (17-position) alkynylation, hydrolysis (to 3-position Methoxy), (perbrominated pyridinium bromide) addition and elimination (dehydrobromination to form a 4,9-position double bond), (3-position ketone group with ethylene glycol) ketalization to prepare the product. |
