D-Mandelonitrile-b-gentiobioside

苦杏仁苷

Amygdalin is a cyanogenic glycoside that has been found in seeds from plants of the Rosaceae family and has diverse biological activities. It induces cell cycle arrest at the G0/G1 phase, decreases cyclin A and Cdk2 levels, and inhibits cell growth in UMUC-3, RT112, and TCCSUP bladder cancer cells when used at concentrations ranging from 1.25 to 10 mg/ml. Amygdalin (3 mg/kg) reduces the number of primary microtubules and microvessels in aortic rings isolated from rats with diabetes induced by streptozotocin. In vivo, amygdalin reduces triglyceride, total cholesterol, and LDL levels and aortic sinus plaque area in an LDLR-/- mouse model of atherosclerosis. It also reduces production of TNF-α, IL-1β, and IL-6, as well as neutrophil and macrophage infiltration, in bronchoalveolar lavage fluid (BALF) in a mouse model of LPS-induced acute lung injury.

Amygdalin analytical standard provided with chromatographic purity, to be used as reference material for qualitative determination.

Amygdalin is a glycoside initially isolated from the seeds of the tree Prunus dulcis, also known as bitter almonds. Several other related species in the genus of Prunus, including apricot and black cherry also contain amygdalin. Since the early 1950s, both amygdalin and a modified form named laetrile or Vitamin B17 have been promoted as cancer cures. However, neither of these compounds nor any other derivatives are vitamins in any sense, and studies have found them to be clinically ineffective in the treatment of cancer, as well as dangerously toxic. They are potentially lethal when taken by mouth, because certain enzymes (in particular, glucosidases that occur in the gut and in various kinds of seeds, edible or inedible) act on them to produce cyanide. The promotion of laetrile to treat cancer has been described in the medical literature as a canonical example of quackery, and as "the slickest, most sophisticated, and certainly the most remunerative cancer quack promotion in medical history." Amygdalin is extracted from almonds or apricot kernels by boiling in ethanol; on evaporation of the solution and the addition of diethyl ether, amygdalin is precipitated as white minute crystals.

Title: Amygdalin

CAS Registry Number: 29883-15-6

CAS Name: [(6-O-b-D-Glucopyranosyl-b-D-glucopyranosyl)oxy]benzeneacetonitrile

Additional Names: amygdaloside; mandelonitrile-b-gentiobioside; D-mandelonitrile-b-D-glucosido-6-b-D-glucoside

Manufacturers' Codes: NSC-15780

Molecular Formula: C20H27NO11

Molecular Weight: 457.43

Percent Composition: C 52.51%, H 5.95%, N 3.06%, O 38.47%

Literature References: The name amygdalin is currently used interchangeably with laetrile. Cyanogenic glycoside which occurs in seeds of Rosaceae; principally in bitter almonds; also in peaches and apricots. Most common constituent of Laetrile® preparations. Structure and synthesis: W. N. Haworth, B. Wylam, J. Chem. Soc. 123, 3120 (1923); Kuhn, Ber. 56, 857 (1923); R. Campbell, W. N. Haworth, J. Chem. Soc. 125, 1337 (1924); Hudson, J. Am. Chem. Soc. 46, 483 (1924); Zemplén, Kunz, Ber. 57, 1357 (1924); Kuhn, Sobotka, ibid. 1767; Baumann, Pigman, The Carbohydrates, W. Pigman, Ed. (Academic Press, New York, 1957) p 550. Enzymic hydrolysis studies: Haisman, Knight, Biochem. J. 103, 528 (1967). The term Laetrile® has also been applied to mandelonitrile b-glucuronide. Purported prepn: E. T. Krebs, E. T. Krebs, Jr., GB 788855 (1958) and US 2985664 (1961). Synthesis, characterization and comparison of mandelonitrile b-glucuronide with amygdalin: C. Fenselau et al., Science 198, 625 (1977). Pharmacology and cyanide toxicity studies of amygdalin (laetrile): C. G. Moertel et al., J. Am. Med. Assoc. 245, 591 (1981); M. M. Ames et al., Cancer Chemother. Pharmacol. 6, 51 (1981). Pharmacokinetics: A. G. Rauws et al., Arch. Toxicol. 49, 311 (1982). Determn methods in tissues and fluids: J. Balkon, J. Anal. Toxicol. 6, 244 (1982). Amygdalin (laetrile) is a toxic drug that is not effective as a cancer treatment: C. G. Moertel et al., N. Engl. J. Med. 306, 201 (1982). Review of the controversial use of amygdalin (laetrile): V. Herbert, Am. J. Clin. Nutr. 32, 1121-1158 (1979).

Derivative Type: Trihydrate

Properties: Orthorhombic columns from water, mp 200°; mp about 220° when anhydr. The once melted and solidif substance remelts at 125-130°. [a]D20 -42° (anhydr basis). One gram dissolves in 12 ml water, in 900 ml alcohol, in 11 ml boiling alcohol. Very sol in boiling water; almost insol in ether. pH of satd aq soln ~7.

Melting point: mp 200°; mp about 220° when anhydr; remelts at 125-130°

Optical Rotation: [a]D20 -42° (anhydr basis)

 NOTE: The misleading term vitamin B17, has sometimes been applied to amygdalin.