Succinic anhydride Estriol succinate

A mixture consisting of 8 grams of estriol, 20 grams of succinic acid anhydride and 60 ml of pyridine is heated at 90 C for 4 hours, after which the reaction mixture is poured into water. The aqueous solution is extracted with ether, the ether layer is separated, washed with diluted sulfuric acid and after that with water until neutral, then evaporated to dryness to obtain 14 grams of an amorphous substance. Melting point 82° to 86°C. This drying residue proves to consist of a mixture of estriol disuccinate and estriol monosuccinate, which are separated by repeated crystallization from a mixture of methanol and water. 

A mixture consisting of 8 grams of estriol, 20 grams of succinic acid anhydride... 

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