| 摘要 |
<p>A process for making a known 6-methyl, 19-nor-pregna-4, 6-diene, 3.20-dione which begins with formylating a 3-alcoxy, 19-nor-pregna-3,5,17(20)-triene at the 6 position. The 6-formylated derivative is reduced to yield a 6-hydroxy methylated derivative, which is in turn dehydrated to a 3-keto, 6-methylenic derivative. The 3-keto derivative is then isomerized to a 3-keto, 4,6,17-pregnatriene. This latter triene is then coverted to the known product by reaction with a bis-hydroxylating agent and a catalyst based on osmium tetroxide. Optionally, the product can be acylated at the 17-alpha position. The process reduces the cost of producing the known product by allowing it to be manufactured from starting materials less costly than those previously required.</p> |
