261. Allicin

Nomenclature

CAS number: 539-86-6
2-Propene-1-sulfinothioic acid S-2-propen-1-yl ester; thio-2-propene-1-sulfinic acid S-allyl ester; diallyl disulfide-oxide.
C6H10OS2; mol wt 162.27.
C 44.41%, H 6.21%, O 9.86%, S 39.52%.

Description and references

A biologically active constit of freshly crushed garlic (Allium sativum L., Liliaceae). Naturally formed by the action of the enzyme allicinase on alliin, q.v., when the tissue of the garlic bulb is disrupted. Isoln and antibacterial activity: C. J. Cavallito, J. H. Bailey, J. Am. Chem. Soc. 66, 1950 (1944). Structure: Cavallito et al., ibid. 1952 DOI. Synthesis: Stoll, Seebeck, Experientia 6, 330 (1950); Cavallito, Small, US 2508745 (1950 to Sterling Drug). Antifungal activity: Y. Yamada, K. Azuma, Antimicrob. Agents Chemother. 11, 743 (1977). Pharmacological effects and prepn: P. R. Mayeux et al., Agents Actions 25, 182 (1988). Stability in blood, solvents, and simulated physiological fluids: F. Freeman, Y. Kodera, J. Agric. Food Chem. 43, 2332 (1995). Identification as the source of garlic's pungent burning and prickling sensations: L. J. Macpherson et al., Curr. Biol. 15, 929 (2005).

Chemical structure

Properties

Yellow liquid. True odor of garlic. Decomp on distilling. d420 1.112. nD20 1.561. Soly in water at 10° about 2.5% w/w. pH about 6.5. Upon standing an oily precipitate forms from aq solns. Miscible with alcohol, ether, benzene; fairly insol in the Skellysolves; unstable to hot alkali; stable to acids. LD50 in mice (mg/kg): 60 i.v.; 120 s.c. (Cavallito, Bailey).