Compound NJ2 is a xanthylium yellowish pigment found in wine.

Compound NJ2
Structure of compound NJ2, a xanthylium pigment found in wine.
Names
IUPAC name
6,20-bis(3,4-dihydroxyphenyl)-7,10,16,19-tetrahydroxy-5,21-dioxa-13-oxoniapentacyclo[12.8.0.03,12.04,9.017,22]docosa-1,3(12),4(9),10,13,15,17(22)-heptaene-2-carboxylic acid
Identifiers
3D model (JSmol)
  • InChI=1S/C32H24O13/c33-15-3-1-11(5-19(15)37)28-21(39)7-13-17(35)9-23-25(30(13)44-28)27(32(41)42)26-24(43-23)10-18(36)14-8-22(40)29(45-31(14)26)12-2-4-16(34)20(38)6-12/h1-6,9-10,21-22,28-29,39-40H,7-8H2,(H6-,33,34,35,36,37,38,41,42)/p+1
    Key: VVMHZAVGHYVZHM-UHFFFAOYSA-O
  • Oc6ccc(cc6O)C7Oc(c5CC7O)c4c(C(=O)O)c(c(cc1O)[o+]c4cc5O)c(c1CC2O)OC2c(cc3O)ccc3O
Properties
C32H25O13+
Molar mass 617.538 g·mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

In model solutions, colorless compounds, such as catechin, can give rise to new types of pigments. The first step is the formation of colorless dimeric compounds consisting of two flavanol units linked by carboxy-methine bridge. This is followed by the formation of xanthylium salt yellowish pigments and their ethyl esters, resulting from the dehydration of the colorless dimers, followed by an oxidation process. The loss of a water molecule takes place between two A ring hydroxyl groups of the colorless dimers.[1]

See also

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References

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  1. ^ Es-Safi, Nour-Eddine; Le Guernevé, Christine; Fulcrand, Hélène; Cheynier, Véronique; Moutounet, Michel (2000). "Xanthylium salts formation involved in wine colour changes". International Journal of Food Science & Technology. 35: 63–74. doi:10.1046/j.1365-2621.2000.00339.x.