| 摘要 |
<p>By the method according to the invention condensation of 11β,16α,17α,21-tetrahydroxy-1,4-pregnadiene-3,20-dione 21-acetate with n-butyric aldehyde is carried out, in the known way, in the medium of hydrofluoric acid of concentration of 70-80 %. Theisolated crude condensation product is crystallized from ethanol and obtained 21-acetate of budesonide (22R) of at least 95 % content is hydrolyzed, and the product thus obtained is crystallized from ethyl acetate.</p> |
