Extraction of Cytisine from Laburnum anagyroides (Golden chain tree) Seeds

To a reflux apparatus with a stirrer add 54g of coarsely powdered laburnum anagyroides seeds, 300ml of 60% ethanol and 30ml of glacial acetic acid, reflux with stirring for 12h. Cool the mixture down and filter, pour the solution into a distillation apparatus and distill the ethanol off. Filter and pour the solution into a beaker, add as much of saturated lead acetate solution until no more brown precipitate precipitates out. Filter and pour the solution into a beaker and pass hydrogen sulfide gas through the solution to precipitate the rest of the dyes and impurities. Filter and make the solution alkaline with sodium hydroxide, filter again. Extract the crude product multiple times with chloroform. Distil the chloroform off and add as much of petroleum ether until no more cytisine precipitates. Filter and recrystallize the cytisine in hot acetone.



The seeds ready to be crushed

index (1)

The ethanolic acetic acid seed mixture

index (2)

The filtered solution

index (3)

Distilling the ethanol off and filtering the mixture

index (4)

The filtered mixture

index (5)

Precipitation of the impurities with lead acetate

index (6)

Precipitation with hydrogen sulfide

index (7)

Filtered solution

index (8)

The solution was alkalized and filtered

index (9)

The crude cytisine

index (10)


index (11)

The pure product

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