Process for obtaining the carbethoxy-siringoyl-methyl-reserpate, characterized in that 100 ml. Of anhydrous pyridine contained in a balloon and two necks are added 12 g of methyl ester and of resºrpico acid. The balloon is immersed in a cooling bath of -40º c. For about 15 minutes, after which syringoyl chloride (10 g), which is dissolved after a short time, is quickly added. The bath temperature is allowed to rise to 0º and then the reaction mass is allowed to stand at about 15ºC for about 12 hours. The solution obtained is poured into 1000 ml of hexane: a substance is filtered off and washed with small amounts of hexane. The product obtained is dissolved in methylene chloride and the solution is washed first with water and then with dilute sodium hydrate solution and finally with water again. The dehydrated solution is concentrated and chromatographed on florisil, using methylene chloride as eluent. The eluation product provides, by distillation of the solvent, a straw-white product. By crystallization from a mixture of acetone-hexane, 14 g of carbethoxy-siringoyl-methyl-reserpate are obtained. (Machine-translation by Google Translate, not legally binding)
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