Sinigrin orallyl glucosinolate is aglucosinolate that belongs to the family ofglucosides found in some plants of the familyBrassicaceae such asBrussels sprouts,broccoli, and the seeds of blackmustard (Brassica nigra). Whenever sinigrin-containing plant tissue is crushed or otherwise damaged, theenzymemyrosinase degrades sinigrin to a mustard oil (allyl isothiocyanate), which is responsible for thepungent taste of mustard andhorseradish.^[1] Seeds of white mustard,Sinapis alba, give a less pungent mustard because this species contains a different glucosinolate,sinalbin.

Sinigrin

Names
IUPAC name (Z)-N-[1-(β-D-glucopyranosylsulfanyl)but-3-en-1-ylidene]hydroxylamine-O-sulfonic acid
Systematic IUPAC name (Z)-N-(1-{[(2S,3R,4S,5S,6R)-3,4,5-trihydroxy-6-(hydroxymethyl)oxan-2-yl]sulfanyl}but-3-en-1-ylidene)hydroxylamine-O-sulfonic acid
Other names Allyl glucosinolate; 2-Propenyl glucosinolate; (1Z)-N-(Sulfooxy)but-3-enimidoyl 1-thio-β-D-glucopyranoside
Identifiers
CAS Number	Sinigrin:534-69-0 Y K+ salt:3952-98-5 Y
3D model (JSmol)	Sinigrin:Interactive image K+ salt:Interactive image
ChEBI	Sinigrin:CHEBI:79317 Y
ChemSpider	Sinigrin:4588961 Y K+ salt:4576678 Y
PubChemCID	Sinigrin:5486549 K+ salt:23684362
UNII	K+ salt:50UM64RMBJ
InChI InChI=1S/C10H17NO9S2/c1-2-3-6(11-20-22(16,17)18)21-10-9(15)8(14)7(13)5(4-12)19-10/h2,5,7-10,12-15H,1,3-4H2,(H,16,17,18)/b11-6-/t5-,7-,8+,9-,10+/m1/s1 Y Key: PHZOWSSBXJXFOR-GLVDENFASA-N Y K+ salt: InChI=1S/C10H17NO9S2.K/c1-2-3-6(11-20-22(16,17)18)21-10-9(15)8(14)7(13)5(4-12)19-10;/h2,5,7-10,12-15H,1,3-4H2,(H,16,17,18);/q;+1/p-1/b11-6-;/t5-,7-,8+,9-,10+;/m1./s1 Key: QKFAFSGJTMHRRY-FVDOMRANSA-M
SMILES Sinigrin: C=CC/C(=N/OS(=O)(=O)O)/S[C@H]1[C@@H]([C@H]([C@@H]([C@H](O1)CO)O)O)O K+ salt: C=CC/C(=N/OS(=O)(=O)[O-])/S[C@H]1[C@@H]([C@H]([C@@H]([C@H](O1)CO)O)O)O.[K+]
Properties
Chemical formula	C10H17NO9S2
Molar mass	359.36 g·mol−1
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). Infobox references

The compound was first reported in 1839,^[2] after its isolation from black mustardBrassica nigra, also known asSinapisnigra, after which it was named.^{[3]: Section 2} Sinigrin is now known to occur widely in otherbrassica families includingBrassicaceae andCapparaceae.^[4]

The chemical structure of sinigrin had been established by 1930. This showed that it is a glucose derivative withβ-D-glucopyranose configuration. It was unclear whether the C=N bond was in theZ (orsyn) form, with sulfur and oxygen substituents on the same side of the double bond, or the alternative E form in which they are on opposite sides. The matter was settled byX-ray crystallography of its potassium salt in 1963.^[5][6] It is now known that all naturalglucosinolates are of Z form.^[3]

Sinigrin is biosynthesised from the amino acidmethionine in a multi-step pathway.^[3]

The first laboratory syntheses of sinigrin was published in 1965.^[2] Later work provided a more efficient route.^{[7][3]: Section 3}

The natural role of glucosinolates are as plant defense compounds. The enzymemyrosinase removes the glucose group in sinigrin to give an intermediate which spontaneously rearranges toallyl isothiocyanate, the compound responsible for the pungent taste ofDijon mustard. This is a reactive material which is toxic to many insect predators and its production is triggered when the plant is damaged.^[8] This effect has been called themustard oil bomb.^[9] Singrin is also known to beallelopathic.^[10] At concentrations typically found in foods, the glucosinolates are not toxic to humans and can be useful flavor components.^[11]

Sinigrin is unusual among the glucosinolates because it is also known to be the natural precursor for other volatile compounds includingepithionitrile,allyl cyanide and allyl thiocyanate.^{[3]: Fig. 22}

• List of phytochemicals in food