Isolation, levopimaric acid from pine

Isolation, levopimaric acid from pine resin, 45, 64... 

Levopimaric Acid. UR)-l,2,3,4,4a,4b-abietadienoic acid i-pimaric acid 0-pimaric acid /-sapietic acid. C HjjOj mol wt 302.44. C 79.42%, H [0.00%. O [0.58%. Isolation from American pine oleoresin Palkin, Harris, J. Am. Chem. Soc. 55, 3677 (1933) from French galipot, from Pinos maritima Ruzicka, Bacon, Heh. Chim. Acta 20, 1542 (1937) from Pittas paiustris Harris, Sanderson, J. Am. Chem. Soc. 70, 334, 3671 (1948). Structure Ruzicka, Kaufmann, Helv. 

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