From Chondodendron tomentosum Ruiz and Pav., Menispermaceae: Faltis, Monatsh. Chem. 33, 873 (1912); Faltis, Neumann, ibid. 42, 311 (1921); Dutcher, J. Am. Chem. Soc. 68, 419 (1946); from the drug Radix pareirae bravae: King, J. Chem. Soc. 1940, 737. Structure: Faltis, Dietreich, Ber. 67, 231 (1934); Jeffreys, J. Chem. Soc. 1956, 4451.