From seeds of Conium maculatum L., Umbelliferae. Isoln: Sp"ath, Adler, Monatsh. Chem. 63, 127 (1933). Stereochemistry: Hill, J. Am. Chem. Soc. 80, 1609 (1958); Sicher, Ticky, Collect. Czech. Chem. Commun. 23, 2081 (1958).