All parts of Allium ursinum, L. (Ger. Barlauch), leaves, flowers and bulb have a most penetrating, garlic-like odor.

Upon distillation of the entire plant, 0,007 p. c. of a strongly refractory oil of dark-brown color was obtained. Its odor, which somewhat resembles that of garlic, is yet quite different therefrom. The taste is burning and pungent; d13o1,015.

The oil distils over almost completely between 95 and 106°. According to Semmler5), it consists principally of vinyl sulphide (C2H3)2S (b.p. 101°; d 0,9125). The constitution of vinyl sulphide is expressed by the following structural formula.

1) Semmler, Arch, der Pharm. 230 (1892), 443. 2) Schimmel's Bericht April 1889, 44.

3) Apotheker Ztg. 18 (1903), 268.

4) In the freshly expressed juice, W. D. Kooper (Zeitschr. Untersuch. d. Nahrungs- u. GenuBm. 19 [1910], 569) found hydrogen sulphocyanide and allylthiocyanate. The presence of formaldehyde, acetaldehyde or acrolein could not be detected.

5) Liebig's Annalen 241 (1887), 90.

In addition, this oil contains polysulphides of vinyl, also a very small amount of a mercaptan, and an aldehyde that has not been further investigated.