Guaiol (CAS 489-86-1) — Woody Base Note Fragrance Ingredient
Guaiol
CAS 489-86-1
What Is Guaiol?
Guaiol is a naturally occurring sesquiterpene alcohol found in guaiac wood oil and cypress. It’s encountered in woody, masculine fragrances and some natural medicinal products. This ingredient matters because it provides a smooth, slightly smoky wood note that bridges fresh and resinous characteristics in perfumery.
Safety Profile
GENERALLY SAFEWhat Does Guaiol Smell Like?
Guaiol presents a complex woody aroma with subtle evolution. The initial impression is dry, pencil-shaving woodiness with a faintly medicinal edge. As it develops, a smooth heart reveals cedar-like facets with whispers of amber. The dry-down lingers as a clean, slightly smoky wood note with exceptional tenacity. Unlike sharper wood notes, guaiol maintains a rounded, almost creamy texture throughout its lifespan on skin.
Scent Profile
In Famous Fragrances
Fragrance associations may not reflect actual formulations.
Guaiol provides the polished wood backbone in this fragrance, blending with iris and vanilla to create a sophisticated ‘woody powder’ effect that defines the scent.
Here guaiol’s dry wood character enhances the sandalwood illusion, adding structural crispness to prevent the composition from becoming too creamy.
2D Molecular Structure
SMILES: C[C@H]1CCC2=C1C[C@@H](CC[C@@H]2C)C(C)(C)O
Chemistry, Properties & Perfumer Guide
The Chemistry
Guaiol is a bicyclic sesquiterpenoid alcohol with the molecular formula C15H26O. It occurs naturally in Guaiacum officinale wood oil (up to 30%) and various cypress species. The molecule features a eudesmane skeleton with a tertiary alcohol group. Industrial production typically involves isolation from guaiac wood oil through fractional distillation, though synthetic routes exist via hydrogenation of guaiazulene. The stereochemistry at C-4 and C-10 positions influences odor characteristics, with (-)-guaiol being the naturally predominant enantiomer.
Physical & Chemical Properties
| Boiling Point | 290-295 °C |
|---|---|
| Density | 0.96 g/cm³ |
| Refractive Index | 1.498-1.502 |
| Flash Point | >100 °C |
Perfumer Guide
| Application | Typical % | Range | Notes |
|---|---|---|---|
| Fine Fragrance | 1-3% | Up to 5% | Woody base note fixative |
| Soap/Cosmetic | 0.5-1% | Up to 2% | Adds dry wood character |
Classic Accords
Tip: Use guaiol to add dryness and structure to overly sweet woody bases without introducing harshness.
Alternatives & Comparisons
When a more pronounced cedar character is desired, though cedrol lacks guaiol’s subtle smokiness.
For deeper, earthier wood notes, though this will significantly alter the fragrance direction.
Safety, Regulatory & Sustainability
⚠ Regulatory Disclaimer
General reference only. IFRA, REACH, EU Cosmetics Regulation standards update periodically. Consult current IFRA Standards Library before formulating. Not legal or regulatory advice.
IFRA Status
No IFRA restrictions. Listed as safe for use in all categories without limitation (IFRA 49th Amendment).
RIFM Assessment
RIFM evaluation confirms guaiol as safe for current fragrance use levels with no sensitization concerns.
Sustainability
Guaiac wood is harvested from slow-growing trees (Guaiacum spp.), raising sustainability concerns. Most commercial guaiol now comes from cypress sources or synthesis. Synthetic production offers consistent quality and reduces pressure on endangered guaiacum populations. Responsible sourcing certifications (FSC) are recommended for natural material.
Explore Guaiol
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References
- Burdock, G.A. (2010). Fenaroli’s Handbook of Flavor Ingredients. CRC Press. ISBN 9781420090869
Data: PubChem (NIH), PubMed, RIFM, IFRA. Last reviewed: Mar 2026.
Report a data errorPhysicochemical Properties
DTXSID: DTXSID40883399
Physical Properties
| Molecular Weight | 222.372 g/mol🔬 EPA CompTox |
| Density | 0.974 g/cm^3📊 OPERA |
| Boiling Point | 291.545 °C📊 OPERA |
| Melting Point | 84.241 °C📊 OPERA |
| Flash Point | 124.2 °C📊 OPERA |
| Refractive Index | 1.503 Dimensionless📊 OPERA |
| Molar Volume | 231.275 cm^3/mol📊 OPERA |
Partition & Solubility
| LogP (Octanol-Water) | 4.287 Log10 unitless📊 OPERA |
| LogD (pH 5.5) | 4.287 Log10 unitless📊 OPERA |
| LogD (pH 7.4) | 4.287 Log10 unitless📊 OPERA |
| LogKoa (Octanol-Air) | 8.99 Log10 unitless📊 OPERA |
| Water Solubility | 0.001 mol/L📊 OPERA |
| Henry's Law Constant | 0 atm-m3/mole📊 OPERA |
Transport Properties
| Vapor Pressure | 0.003 mmHg📊 OPERA |
| Viscosity | 13.684 cP📊 OPERA |
| Surface Tension | 33.433 dyn/cm📊 OPERA |
| Thermal Conductivity | 127.031 mW/(m*K)📊 OPERA |
Molecular Descriptors
| Topological Polar Surface Area | 20.23 Ų💻 Computed |
| H-Bond Donors | 1 count💻 Computed |
| H-Bond Acceptors | 1 count💻 Computed |
| Rotatable Bonds | 1 count💻 Computed |
| Aromatic Rings | 0 count💻 Computed |
| Molar Refractivity | 68.34 cm^3/mol📊 OPERA |
| Polarizability | 27.092 Å^3📊 OPERA |
Data Sources:
🔬 EPA Experimental data from U.S. EPA CompTox Chemicals Dashboard & CTX APIs. 📊 OPERA Predicted using EPA's OPERA QSAR models. 💻 Computed Calculated from SMILES using RDKit.
