Found in seeds of Anagyris foetida L., Leguminosae and in gorse (Ulex europaeus L., Leguminosae). Isoln: Ing, J. Chem. Soc. 1933, 504; Orekhov et al., Ber. 67, 1394 (1934); Couch, J. Am. Chem. Soc. 61, 3327 (1939); Briggs, Russell, J. Chem. Soc. 1942, 507; Galinsky, Stern, Ber. 77, 132 (1944); Faugeras, Ann. Pharm. Fr. 29, 241 (1971). Absolute configuration: Okuda et al., Chem. Ind. (London) 1961, 1116; Okuda et al., Chem. Pharm. Bull. 13, 491 (1965). Synthesis: van Tamelen, Baran, J. Am. Chem. Soc. 80, 4659 (1958); Goldberg, Lipkin, J. Org. Chem. 37, 1823 (1972).