METHOD AND APPARATUS FOR THE SYNTHESIS OF DIHYDROARTEMISININ AND ARTEMISININ DERIVATIVES

摘要

The present invention is directed to a method for continuous production of dihydroartemisinin and also artemisinin derivatives derived from dihydroartemisinin by using artemisinin or dihydroartemisinic acid (DHAA) as starting material as well as to a continuous flow reactor for producing dihydroartemisinin as well as the artemisinin derivatives. It was found that the reduction of artemisinin to dihydroartemisinin in a continuous process requires a special kind of reactor and a special combination of reagents comprising a hydride reducing agent, at least one activator such as an inorganic activator, at least one solid base, at least one aprotic solvent and at least one C1-C5 alcohol.

主权项

1. A method for reducing artemisinin in a continuous manner comprising the following steps:
1) providing a column containing a hydride reducing agent, at least one activator and at least one solid base or providing a first column containing at least one solid base and a second column containing a hydride reducing agent and at least one activator, 2) providing a continuous flow of a solution of artemisinin in at least one aprotic solvent containing at least one C1-C5 alcohol through the column containing the hydride reducing agent, the at least one activator and the at least one solid base or through the first column containing the at least one solid base and the second column containing the hydride reducing agent and the at least one activator, 3) thereby reducing artemisinin in a continuous manner to dihydroartemisinin of the following formula