Abietic acid

Abietic acid (also known as abietinic acid or sylvic acid) is a mild organic acid found in coniferous trees.

Abietic acid

Names
IUPAC name Abieta-7,13-dien-18-oic acid
Systematic IUPAC name (1R,4aR,4bR,10aR)-1,4a-Dimethyl-7-(propan-2-yl)-1,2,3,4,4a,4b,5,6,10,10a-decahydrophenanthrene-1-carboxylic acid
Other names Abietinic acid; Sylvic acid
Identifiers
CAS Number	514-10-3 Y
3D model (JSmol)	Interactive image
ChEBI	CHEBI:28987 Y
ChEMBL	ChEMBL71893 Y
ChemSpider	10127 Y
ECHA InfoCard	100.007.436
EC Number	208-173-3
KEGG	C06087 Y
PubChem CID	10569
RTECS number	TP8580000
UNII	V3DHX33184 Y
CompTox Dashboard (EPA)	DTXSID7022047
InChI InChI=1S/C20H30O2/c1-13(2)14-6-8-16-15(12-14)7-9-17-19(16,3)10-5-11-20(17,4)18(21)22/h7,12-13,16-17H,5-6,8-11H2,1-4H3,(H,21,22)/t16-,17+,19+,20+/m0/s1 Y Key: RSWGJHLUYNHPMX-ONCXSQPRSA-N Y InChI=1/C20H30O2/c1-13(2)14-6-8-16-15(12-14)7-9-17-19(16,3)10-5-11-20(17,4)18(21)22/h7,12-13,16-17H,5-6,8-11H2,1-4H3,(H,21,22)/t16-,17+,19+,20+/m0/s1 Key: RSWGJHLUYNHPMX-ONCXSQPRBK
SMILES O=C(O)[C@]3([C@@H]2C/C=C1/C=C(\CC[C@@H]1[C@@]2(C)CCC3)C(C)C)C
Properties
Chemical formula	C20H30O2
Molar mass	302.458 g·mol−1
Appearance	Yellow resinous powder, crystals or chunks. Monoclinic plates (from EtOH/water). Colorless solid when pure.
Density	1.06 g/mL
Melting point	172–175 °C (342–347 °F; 445–448 K)[1]
Boiling point	250 °C; 482 °F; 523 K
Solubility in water	Insoluble[1]
Solubility in other solvents	Very soluble in acetone, petroleum ether, Et2O, and ethanol
Hazards
Occupational safety and health (OHS/OSH):
Main hazards	Irritant
GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H317
Precautionary statements	P261, P272, P280, P302+P352, P321, P333+P313, P363, P501
NFPA 704 (fire diamond)	1 0 0
Safety data sheet (SDS)	MSDS
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Y verify (what is YN ?) Infobox references

It is a commercially important component of paints, soaps, foods, and soldering flux, and is the primary component of resin acid.

Characteristics

Abietic acid is found in pine trees, including:

• Pinus insularis (Khasi Pine)
• Pinus kesiya Royle
• Pinus strobus (Eastern White Pine)
• Pinus sylvestris (Scots Pine).^[2]

Pure abietic acid is a colorless solid, but commercial samples are usually a glassy or partly crystalline yellowish solid that melts at temperatures as low as 85 °C (185 °F).^[3]

Abietic acid is soluble in alcohols, acetone, and ethers. Its ester or salt is called an abietate.^[4]

Abietic acid belongs to the abietane diterpene group of organic compounds derived from four isoprene units.

Preparation

Abietic acid is extracted from tree rosin^[5] (via isomerization) and is the most abundant of several closely related organic acids that constitute most of rosin, the solid portion of the oleoresin of coniferous trees.

Resin acids are converted into ester gum by reaction with controlled amounts of glycerol or other polyhydric alcohols.

Uses

Abietic acid has drying properties, and as ester gum is used in paints, varnishes, and lacquers.^[3]

It is also used in soaps, for the analysis of resins, and the preparation of metal resinates.

As rosin

Rosin, of which abietic acid is the principal component:

• Has been used for centuries as a flux for soldering. (Abietic acid in the flux removes oxidation from the surfaces of metals, increasing their ability to bond with the liquified solder.)
• Is rubbed on the hair of a violin bow to increase friction.
• Has been used for centuries for caulking ships.^[3]
• Is approved by the US FDA as a miscellaneous food additive.^[6]

Safety

• As the chief component of rosin, abietic acid is approved by the US FDA as a miscellaneous food additive.^[6]
• Abietic acid is considered a "nonhazardous natural substance" in tall oil ("liquid rosin").^[4]
• In the U.S., abietic acid is listed in the inventory of the Toxic Substances Control Act.
• Abietic acid is the primary irritant in pine wood and resin. As a contact allergen^[7] it is the cause of abietic acid dermatitis. (However, compounds resulting from its oxidation by air elicit stronger responses.) ^[8]
• 50% ethanol extracts from Resina pini of Pinus sp. (Pinaceae) showed inhibitory activity against testosterone 5α-reductase prepared from rat prostate. The fraction responsible for this activity was purified, and the active constituent was isolated and identified as abietic acid, which exhibited potent inhibitory activity against testosterone 5α-reductase in vitro.^[9]

References

1. Merck Index, 12th Edition, 3. Abietic Acid
2. "Abietic Acid". Dr. Duke's Phytochemical and Ethnobotanical Databases. Archived from the original on 2015-09-23. Retrieved 13 January 2012.
3. Hoiberg, Dale H., ed. (2010). "abietic acid". Encyclopædia Britannica. Vol. I: A-ak Bayes (15th ed.). Chicago, Illinois: Encyclopædia Britannica Inc. pp. 32. ISBN 978-1-59339-837-8.
4. Lars-Hugo Norlin "Tall Oil" in Ullmann's Encyclopedia of Industrial Chemistry 2002, Wiley-VCH, Weinheim.doi:10.1002/14356007.a26_057
5. G. C. Harris and T. F. Sanderson (1963). "Abietic Acid". Organic Syntheses. 32: 1; Collected Volumes, vol. 4, p. 1.
6. Nutrition, Center for Food Safety and Applied (2022-08-25). "Food Additive Status List". FDA.
7. El Sayed, F; Manzur, F; Bayle, P; Marguery, MS; Bazex, J (1995). "Contact urticaria from abietic acid". Contact Dermatitis. 32 (6): 361–2. doi:10.1111/j.1600-0536.1995.tb00628.x. PMID 7554886. S2CID 36139468.
8. Hausen, BM; Krohn, K; Budianto, E (1990). "Contact allergy due to colophony (VII). Sensitizing studies with oxidation products of abietic and related acids". Contact Dermatitis. 23 (5): 352–8. doi:10.1111/j.1600-0536.1990.tb05171.x. PMID 2096024. S2CID 34726630.
9. Seong-Soo Roh, Moon-Ki Park and Yong-ung Kim (2010). "Abietic Acid from Resina Pini of Pinus Species as a Testosterone 5α-Reductase Inhibitor". J. Health Sci. 56 (4): 451–455. doi:10.1248/jhs.56.451.

External links

• Abietic acid MS Spectrum
• Wolfram Alpha Page