Abundant plant triterpene. Occurs in the skin of lupin seeds, in chicle, in the latex of fig trees and of rubber plants. Was detected in cocoons of Bombyx mori. Isoln: Cohen, Rec. Trav. Chim. 28, 368 (1909); Ruzicka et al., Helv. Chim. Acta 20, 1567 (1937). Identity with β-viscol: Meyer, Jeger, ibid. 31, 1868 (1948). Identity with monogynol B: Chatterji et al., J. Sci. Ind. Res. 18B, 262 (1959). Structure: Ruzicka et al., Helv. Chim. Acta 28, 942 (1945); Ames et al., J. Chem. Soc. 1951, 450. Structure of hydrochloride: Halsall et al., ibid. 1952, 2862. Configuration: Barton, Holmes, ibid. 1952, 78; Djerassi et al., J. Am. Chem. Soc. 77, 5330 (1955). NMR studies: Buckley et al., Chem. Ind. (London) 1971, 298. Total synthesis: Stork et al., J. Am. Chem. Soc. 93, 4945 (1971).