Rotundone (CAS 18374-76-0) — Spicy Middle to base Note Fragrance Ingredient
Rotundone
CAS 18374-76-0
What Is Rotundone?
Rotundone is a powerful aroma compound that gives black pepper its characteristic spicy kick. You encounter it in gourmand fragrances and some natural spice extracts. This molecule matters because it’s detectable at extremely low concentrations, making it a cost-effective way to add peppery warmth to compositions.
Safety Profile
GENERALLY SAFEWhat Does Rotundone Smell Like?
Rotundone delivers an intense, dry peppery burst reminiscent of freshly cracked black peppercorns. The initial sharpness gradually reveals woody undertones and a subtle grapefruit-like citrus facet. In drydown, it leaves a warm, slightly smoky trail that enhances other spice notes. At ultra-low levels, it creates intriguing peppery halo effects around floral notes.
In Famous Fragrances
Fragrance associations may not reflect actual formulations.
Uses rotundone’s peppery sharpness to contrast with warm amber and dry woods, creating a modern spice accord.
Amplifies rotundone’s natural pepper character into an avant-garde solinote fragrance experience.
2D Molecular Structure
SMILES: [H][C@]1(CC[C@H](C)C2=C(C1)[C@@H](C)CC2=O)C(C)=C
Chemistry, Properties & Perfumer Guide
The Chemistry
Rotundone is a sesquiterpenoid ketone first identified in black pepper (Piper nigrum) and later found in Shiraz grapes. Its bicyclic structure contains a unique spiro[4.5]decane framework. Industrially produced via oxidation of α-gurjunene or total synthesis from simpler terpenes. The (+) enantiomer occurs naturally and has stronger aroma characteristics than the (-) form.
Physical & Chemical Properties
| Molecular Weight | 218.33 g/mol |
|---|---|
| Boiling Point | 310 °C (estimated) |
| XLogP | 4.1 |
Perfumer Guide
| Application | Typical % | Range | Notes |
|---|---|---|---|
| Fine Fragrance | 0.001-0.01% | Up to 0.1% | Extremely potent – use sparingly |
| Functional Fragrance | 0.0001-0.001% | Up to 0.01% | For fabric softeners and detergents |
Classic Accords
Tip: Always pre-dilute to 0.1% or lower before incorporating into blends due to extreme potency.
Alternatives & Comparisons
Less sharp than rotundone, with cooling minty-pepper character suitable for fresh applications.
Safety, Regulatory & Sustainability
⚠ Regulatory Disclaimer
General reference only. Consult current IFRA Standards Library before formulating.
IFRA Status
No IFRA restrictions. Listed on IFRA Transparency List.
RIFM Assessment
RIFM assessment complete – no significant safety concerns at current usage levels.
Sustainability
Synthetic production avoids agricultural impacts of pepper cultivation. Modern catalytic methods minimize waste and energy use. Biodegradable with low environmental persistence.
Explore Rotundone
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References
- Wood et al. (2008). From Wine to Pepper: Rotundone, an Obscure Sesquiterpene. J. Agric. Food Chem. DOI: 10.1021/jf800183t
- PubChem CID 6436235 PubChem Rotundone
Data: PubChem (NIH), PubMed, RIFM, IFRA. Last reviewed: Apr 2026.
Report a data errorIngredient Data Sheet
CAS 18374-76-0Physical Properties
| Molecular Weight | 218.33 g/mol🔬 PubChem |
| LogP (Octanol-Water) | 3.7🔬 PubChem |
| Boiling Point | 298 °C🔬 EPA CompTox |
| Vapor Pressure | 0.002 mmHg @ 25°C📊 OPERA |
| Flash Point | 146.5 °C🔬 EPA CompTox |
| Involatility Index | 0.0001💻 Calculated |
| log Kp (skin permeability) | -1.405💻 Calculated |
| SMILES | CC1CCC(CC2=C1C(=O)CC2C)C(=C)C🔬 PubChem |
Volatility & Performance
| Fragrance Note | Base💻 Calculated |
| Volatility Class | Very slow💻 Calculated |
| Persistence Score | 5.7 / 5💻 Calculated |
Odor & Flavor
| Functional Groups | ketonealkene💻 RDKit |
Sensory Thresholds
| Odor Detection Threshold | 0 ppm📖 van Gemert |
Physical data: PubChem (NIH/NLM), U.S. EPA CompTox Dashboard, EPA OPERA models, RDKit. Odor & flavor: Arctander (Perfume & Flavor Chemicals), Fenaroli's Handbook of Flavor Ingredients, Leffingwell. Thresholds: van Gemert (Compilations of Odour Threshold Values). Regulatory: IFRA Standards 51st, FEMA GRAS. Trade names: Surburg (Common Fragrance & Flavor Materials). All data compiled and cross-referenced for perfumertools.com.
Physicochemical Properties
DTXSID: DTXSID301030485
Physical Properties
| Molecular Weight | 218.34 g/mol🔬 EPA CompTox |
| Density | 0.981 g/cm^3📊 OPERA |
| Boiling Point | 306.699 °C📊 OPERA |
| Melting Point | 43.903 °C📊 OPERA |
| Flash Point | 136.003 °C📊 OPERA |
| Refractive Index | 1.501 Dimensionless📊 OPERA |
| Molar Volume | 225.55 cm^3/mol📊 OPERA |
Partition & Solubility
| LogP (Octanol-Water) | 4.189 Log10 unitless📊 OPERA |
| LogD (pH 5.5) | 4.189 Log10 unitless📊 OPERA |
| LogD (pH 7.4) | 4.189 Log10 unitless📊 OPERA |
| LogKoa (Octanol-Air) | 7.46 Log10 unitless📊 OPERA |
| Water Solubility | 0.001 mol/L📊 OPERA |
| Henry's Law Constant | 0.001 atm-m3/mole📊 OPERA |
Transport Properties
| Vapor Pressure | 0.001 mmHg📊 OPERA |
| Surface Tension | 34.096 dyn/cm📊 OPERA |
Molecular Descriptors
| Topological Polar Surface Area | 17.07 Ų💻 Computed |
| H-Bond Donors | 0 count💻 Computed |
| H-Bond Acceptors | 1 count💻 Computed |
| Rotatable Bonds | 1 count💻 Computed |
| Aromatic Rings | 0 count💻 Computed |
| Molar Refractivity | 66.453 cm^3/mol📊 OPERA |
| Polarizability | 26.344 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.
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