| 摘要 |
The invention relates to a new process for the preparation of eburnamonine derivatives of the general Formula I <IMAGE> (I) (wherein R1 is an alkyl group having 1-6 carbon atoms) and optical and geometrical isomers thereof which comprises reacting a hydroxyimino-octahydro-indolo[2,3-a]quinolizine derivative of the general Formula II <IMAGE> (II) (wherein R1 is as stated above and R2 stands for an alkyl group having 1-6 carbon atoms being identical with or different from R1, or a hydrogen atom) or an acid addition salt thereof in an organic protic solvent or solvent mixture with an inorganic base, optionally under the addition of water or an aqueous mineral acid, at a temperature between 60 DEG C. and 200 DEG C. The compounds of the present invention are known drugs having blood pressure decreasing and cerebral vasodilatatory effect. The advantage of the process of the present invention is that it is readily feasible on industrial scale too, provides isomer-free pure products with high yield and requires the use of readily available simple starting materials. |
