Plicatic acid

Plicatic acid

IUPAC name (1S,2S,3R)-1-(3,4-Dihydroxy-5-methoxyphenyl)-2,3,7-trihydroxy-3-(hydroxymethyl)-6-methoxy-1,4-dihydronaphthalene-2-carboxylic acid
Identifiers
CAS number	16462-65-0^Y
PubChem	104836
ChemSpider	94630^Y
Jmol-3D images	Image 1
SMILES O=C(O)[C@]2(O)[C@H](c1c(cc(OC)c(O)c1)C[C@@]2(O)CO)c3cc(O)c(O)c(OC)c3
InChI InChI=1S/C20H22O10/c1-29-14-5-10-7-19(27,8-21)20(28,18(25)26)16(11(10)6-12(14)22)9-3-13(23)17(24)15(4-9)30-2/h3-6,16,21-24,27-28H,7-8H2,1-2H3,(H,25,26)/t16-,19+,20+/m0/s1^Y Key: PGFBYAIGHPJFFJ-PWIZWCRZSA-N^Y InChI=1/C20H22O10/c1-29-14-5-10-7-19(27,8-21)20(28,18(25)26)16(11(10)6-12(14)22)9-3-13(23)17(24)15(4-9)30-2/h3-6,16,21-24,27-28H,7-8H2,1-2H3,(H,25,26)/t16-,19+,20+/m0/s1 Key: PGFBYAIGHPJFFJ-PWIZWCRZBT
Properties
Molecular formula	C₂₀H₂₂O₁₀
Molar mass	422.38 g mol⁻¹
Y (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Plicatic acid is a carboxylic acid from the resin acid group. It is naturally found in thuja and cypress resin. It is the main irritant and contact allergen present in thuja wood. (Cf. pine, where the primary irritant is abietic acid.)

The highest concentrations of plicatic acid can be found in Thuja plicata (Western Redcedar), but Thuja occidentalis (Eastern Arborvitae) and Cryptomeria japonica (Sugi) contain it in significant proportions as well.

Exposure to plicatic acid or thuja wood dust can worsen asthma and provoke allergic reactions.^[1]

References

^ Ayars, GH; Altman, LC; Frazier, CE; Chi, EY (1989). "The toxicity of constituents of cedar and pine woods to pulmonary epithelium". The Journal of allergy and clinical immunology 83 (3): 610–8. PMID 2926083.