HRID918384

反应详情

EQUATION

反应方程式

HRID 918384 的结构方程式

AUXILIARIES

试剂、催化剂与溶剂

1

PROCEDURE

实验过程

A solution of 2-(tetrahydropyran-2-yl)oxy-1-diazoethane (prepared from 69.1 g of N-[2-(tetrahydropyran-2-yl-oxy)ethyl]urea by the procedure described in Example 18) in 600 ml of 3:1 ether-pentane is stirred with 200 ml each of ether and methanol at 0°C. 14 g of 11β,16α,17,21-tetrahydroxypregna-1,4-diene-3,20-dione, 16,17-cycloborate is added in portions. After nitrogen evolution ceases the solvents are removed in vacuo and the residue is dissolved in chloroform and chromatographed on a 150 g-silica gel column. Elution with chloroform and then 1:1 chloroform-ethyl acetate gives 4.0 g of TLC pure 16α-[2-(tetrahydropyran-2-yloxy)ethoxy]11β,17,21-trihydroxypregna-1,4-diene-3,20-dione.

WORKUP

后处理

  1. customare removed in vacuo
  2. dissolutionthe residue is dissolved in chloroform
  3. customchromatographed on a 150 g-silica gel column
  4. washElution with chloroform