| abstract |
The invention relates to the preparation of novel acyl-g-butyrolactones, which are valuable intermediates for the preparation of pharmacologically active Tetrahydropyridazinonderivate. Invention task is the provision of a manufacturing process for the new compounds. According to the invention, the compounds of the formula II are prepared by reacting 4-substituted-4-keto-butyric acid with formaldehyde with addition of catalyst and subsequent acidification at elevated temperature. The tetrahydropyridazinone derivatives which can be prepared with the new intermediates can be used in medicine, in particular, as cardiovascular agents. |