Oleum Asari canadensis. - Canadisches Schlangenwurzelol. - Essence de Serpentaire du Canada.
Origin and Production. Asarum canadense, L. is known in the United States by the popular names of Canada snakeroot, wild ginger and Canadian asarabacca. The rhizome contains a fragrant volatile oil which is largely used in perfumery in North l) Arch, der Pharm. 226 (1888), 89. - Berl. Berichte 21 (1888), 1057. 2) Arch, der Pharm. 227 (1889), 543.
America. Upon distillation the dry rhizome yield 3 to 4,5 p. c. of oil, the rootlets, which are less rich in oil, 1 to 3 p. c.
Properties. The oil possesses a yellow or yellowish-brown color, and a strong, pleasant, aromatic odor and taste. The properties of the oil from the rootlets differ but little from those of the oil distilled from the rhizome1). The constants of two oils distilled from comminuted rhizome with rootlets were as follows: 1. d15o0,9508; aD - 22°0'; nD20o 1,48537; A.V. 3,7; E.V. 115,9; E. V. after acetylation 140,1; soluble in 2,7 vol. and more of 70 p. c. alcohol.
2. d15o0,9519; aD - 10°30'; nD20o1,48987; A.V. 4,7; E.V. 74,7; E.V. after acetylation 125,0; soluble in 2,5 vol. and more of 70 p. c. alcohol.
Oils obtained from the rhizomes without the rootlets had the following properties: 1. d14o0,9516; aD - 2°50'; nD20o 1,48508; A.V. 3,7; E.V. 117,6; E.V. after acetylation 137,2; soluble in 2,3 vol. and more of 70 p. c. alcohol.
2. d15o0,9520; aD - 10°42'; nD20o1,48863; A.V. 3,1; E.V.86,1; E.V. after acetylation 125,8; soluble in 2,3 vol. and more of 70 p. c. alcohol.
An oil distilled from the rootlets had the following properties : d15o0,9659; aD - 39°40'; nD20o 1,50280; A.V. 2,2; E.V. 39,2; E.V. after acetylation 110,2; not soluble in 10 vol. of 70 p.c. alcohol, soluble in 0,9 vol. and more of 80 p. c. alcohol.
Two normal distillates (commercial oils) showed d15o0,9593 and 0,952; aD - 1°42' and - 3°24'.
A distillate from dry rhizome and herb began to congeal at 20° and had the following properties: d20o1,0446; d25o 1,0406; it was soluble in 0,5 vol. of 80 p. c. and in 2 vol. of 70 p. c. alcohol; upon the addition of 8 vol. of alcohol of the same strength the latter solution deposited crystals.
Composition. After the oil had been examined as early as 1880 by F. B. Power2) it was subjected to a renewed examination in 1902 by the same investigator in collaboration with F. B. Lees1). The following constituents are now known: 1. A phenol C9H12O22). 2. a-Pinene (m. p. of nitrol piperidide 118 to 119°), apparently a mixture of both optically active modifications. 3. d-Linalool (oxidation to citral; m. p. of naphthocinchoninic acid 195 to 198°). In the first investigation this alcohol was named asarol.
1) Report of Schimmel & Co. April 1908, 98 and April 1909, 85.
2) On the constituents of the rhizome of Asarum canadense, L, Dissertation, StraBburg 1880. - Proceed. Americ. Pharm. Ass. 28 (1880), 464. - Pharm. Rundsch. (New York) 6 (1888), 101.
5. 1-a-Terpineol (m. p. of dipentene dihydriodide 80°; oxidation to ketolactone C10H16O3, m.p. 62°). 6. Geraniol (m.p. of diphenyl-urethane 81 to 82). 7. Methyleugenol (oxidation to veratric acid; m. p. of bromeugenol methyl ether dibromide 78 to 79°). 8. A blue oil of doubtful composition, consisting of oxygenated compounds alcoholic in character. 9. A lactone C14H20O2. 10. Palmitic acid. 11. Acetic acid and 12. a mixture of higher and lower fatty acids.
The eugenol methyl ether content, determined for the original oil according to Zeisel's method, amounted to 36,9 p. c; the ester content, computed as C2H3O2C10H17, to 27,5 p. c. The total alcohol content C10H18O was found to be 34,9 p. c. which shows that about 13,3 p. c. of the alcohol were present not as ester but free. As there were likewise about 2 p. c. of pinene, the high boiling portion, including the blue oil, amounts to about 20 p.c.