Spinochrome B (2,3,5,7-tetrahydroxynaphthoquinone) is an organic compound with formula C
10
H
6
O
4
, formally derived from 1,4-naphthoquinone through the replacement of four hydrogen atoms by hydroxyl (OH) groups.

Spinochrome B
Skeletal formula
Ball-and-stick model
Names
Preferred IUPAC name
2,3,5,7-Tetrahydroxynaphthalene-1,4-dione
Identifiers
3D model (JSmol)
ChemSpider
UNII
  • InChI=1S/C10H6O6/c11-3-1-4-6(5(12)2-3)8(14)10(16)9(15)7(4)13/h1-2,11-12,15-16H checkY
    Key: RWRKDUHFUYRCIT-UHFFFAOYSA-N checkY
  • InChI=1/C10H6O6/c11-3-1-4-6(5(12)2-3)8(14)10(16)9(15)7(4)13/h1-2,11-12,15-16H
    Key: RWRKDUHFUYRCIT-UHFFFAOYAA
  • O=C(C1=C2C(O)=CC(O)=C1)C(O)=C(O)C2=O
  • Oc1cc(O)c2c(c1)C(=O)C(\O)=C(\O)C2=O
Properties
C10H6O6
Molar mass 222.15 g/mol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)

Spinochrome B occurs naturally as pigment in the shell and spines of sea urchins such as the Japanese dull red species aka-uni (Pseudocentrotus depressus), the greenish-black murasaki-uni (Heliocidaris crassispina), and the brown bafun-uni (Strongylocentrotus pulcherrimus).[1][2] It is soluble in methanol and crystallizes as bright red needles that sublime above 200 °C.[2]

The compound gives a greenish yellow solution when treated with sodium hydroxide, a green solution with ferric chloride, and a green precipitate with lead acetate. It forms a fourfold acetate ester, C
10
H
2
O
2
(CH
3
COO
)4, that crystallizes from methanol as yellow needles that melt at 157 °C.[2]

See also

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References

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  1. ^ Chika KURODA and Masae OKAJIMA (1958), Studies on the Derivatives of Naphthoquinones, XIV. The pigments of sea urchins, IX. Proc. Japan Acad., volume 34, pages 616--618. Online version accessed on 2010-02-01. Pigment M2 is drawn as 2,3,6,8-thNQ but that is the same as 2,3,5,7-thNQ. The genus Heliocedaris should be Heliocidaris and the species purcherrmus should be pulcherrimus.
  2. ^ a b c Chika KURODA and Masae OKAJIMA (1967), Studies on the Derivatives of Naphthoquinones, XVIII. The pigments of sea urchins, XIII. Proc. Japan Acad., volume 43, pages 41--44. Online version accessed on 2010-02-01.