Flavonoids, chemistry isoflavones

Fig 2.1 Early contributions to the flavonoid chemistry of the Leguminosae. The isoflavone glucoside, ononin (1), first obtained from the roots of Ononis spinosa (spiny restharrow) by Reinsch in 1842. Robinin (2), a flavonol 3,7-O-glycoside from the flowers of Robinia pseudoacacia (black locust tree), first mentioned in the literature by Zwenger and Dronke in 1861. 

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