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alkannin

Structure via PubChem · Public domain (PubChem)

EntityQ418237· pop 14· linked from 21 articles

Also known as alkanet extract, C.I. Natural red 20, Anchusaic acid, Anchusin

Alkannin is a natural dye that is obtained from the extracts of the plant dyer's alkanet (Alkanna tinctoria) which is found in the Mediterranean region. The dye is used as a food coloring and in cosmetics; within the European E number schedule, it is numbered E103. It is used as a red-brown food additive in regions such as Australia. Alkannin is deep red in an acid and blue in an alkaline environment. The chemical structure as a naphthoquinone derivative was first determined by Hans Brockmann in 1936. The (R)-enantiomer of alkannin is known as shikonin, and the racemic mixture of the two is kn

Chemical data

Formula
C16H16O5
Molecular weight
288.29 g/mol
IUPAC name
5,8-dihydroxy-2-[(1S)-1-hydroxy-4-methylpent-3-enyl]naphthalene-1,4-dione
SMILES
CC(=CC[C@@H](C1=CC(=O)C2=C(C=CC(=C2C1=O)O)O)O)C
InChIKey
NEZONWMXZKDMKF-JTQLQIEISA-N
XLogP
3
Polar surface area
94.8 Ų
H-bond donors
3
H-bond acceptors
5
Formal charge
0

via PubChem

Drug data · ChEMBL

Molecule type
Small molecule

via ChEMBL · EBI

Wikidata facts

Mass
288.1
Show 6 more facts
Commons category
Alkannin
found in taxon
Arnebia decumbens
chemical formula
C₁₆H₁₆O₅
isomeric SMILES
CC(=CC[C@@H](C1=CC(=O)C2=C(C=CC(=C2C1=O)O)O)O)C
canonical SMILES
CC(=CCC(C1=CC(=O)C2=C(C=CC(=C2C1=O)O)O)O)C
natural product of taxon
Alkanna tinctoria
Sources (2)

via Wikidata · CC0

~1 min read

Encyclopedic overview

3 sections
Contents
  • Biosynthesis
  • Research
  • References

Alkannin is a natural dye that is obtained from the extracts of the plant dyer's alkanet (Alkanna tinctoria) which is found in the Mediterranean region. The dye is used as a food coloring and in cosmetics; within the European E number schedule, it is numbered E103. It is used as a red-brown food additive in regions such as Australia. Alkannin is deep red in an acid and blue in an alkaline environment. The chemical structure as a naphthoquinone derivative was first determined by Hans Brockmann in 1936. The (R)-enantiomer of alkannin is known as shikonin, and the racemic mixture of the two is known as shikalkin.

== Biosynthesis == The enzyme 4-hydroxybenzoate geranyltransferase utilizes geranyl diphosphate and 4-hydroxybenzoic acid to produce 3-geranyl-4-hydroxybenzoic acid and diphosphate. These compounds are then used to form alkannin.

Excerpted from Wikipedia’s “alkannin” article, available under the CC BY-SA 4.0 licence.