(1a.alpha.,4.alpha.,7a.alpha.)-1a,3,3,4,6,6-Hexamethyl-1a,2,3,4,5,6,7,7a-octahydronapth[3,3-b]oxirene (CAS 94400-98-3) — Woody Base Note Fragrance Ingredient

ByThe Good Scents
Woody · Balsamic

(1a.alpha.,4.alpha.,7a.alpha.)-1a,3,3,4,6,6-Hexamethyl-1a,2,3,4,5,6,7,7a-octahydronapth[3,3-b]oxirene

CAS 94400-98-3

Origin
synthetic
Note
Base
IFRA
Use with awareness
Data as of: Apr 2026

What Is (1a.alpha.,4.alpha.,7a.alpha.)-1a,3,3,4,6,6-Hexamethyl-1a,2,3,4,5,6,7,7a-octahydronapth[3,3-b]oxirene?

This synthetic fragrance ingredient is a complex polycyclic compound used in niche perfumery to create unique woody-amber effects. It’s found in avant-garde fragrances pushing olfactory boundaries. As a modern aroma chemical, it represents perfumery’s cutting edge – offering novel scent profiles impossible to achieve with traditional materials.

Safety Profile

USE WITH AWARENESS
Generally safeUse with awarenessProfessional use
✓ Stable under normal use conditions
⚠ Limited safety data available
CAS
94400-98-3
Formula
Mixture
MW
Variable
Odor Family
Woody · Balsamic
Layer 1 · Enthusiast

What Does (1a.alpha.,4.alpha.,7a.alpha.)-1a,3,3,4,6,6-Hexamethyl-1a,2,3,4,5,6,7,7a-octahydronapth[3,3-b]oxirene Smell Like?

A mysterious chameleon with shifting facets – begins with crisp ozonic top notes reminiscent of mountain air, then unfolds into a complex heart of fossilized resins and ancient woods. The dry-down reveals a haunting mineralic quality, like sun-warmed stones by a desert oasis, with subtle animalic undertones that emerge hours after application.

Scent Profile
Layer 2

2D Molecular Structure

Naphth[2,3-b]oxirene, 1a,2,3,4,5,6,7,7a-octahydro-1a,3,3,4,6,6-hexamethyl-, (1aR,4S,7aS)-rel-

SMILES: C[C@H]1CC(C)(C)C2=C(C[C@@]3(C)O[C@H]3C2)C1(C)C

Chemistry, Properties & Perfumer Guide

The Chemistry

This synthetic polycyclic oxirene belongs to the family of epoxy terpenoids, created through advanced organic synthesis techniques. The strained oxirene ring contributes to its unique olfactory properties. While not found in nature, its structural motifs resemble oxidized sesquiterpenes found in aged essential oils. The rigid polycyclic framework provides exceptional stability and longevity in fragrance applications.

Physical & Chemical Properties

Perfumer Guide

Note Position
Base
Volatility
Very low (24+ hours)
Blending
Challenging
ApplicationTypical %RangeNotes
Fine Fragrance0.1-0.5%Up to 1%Powerful base note modifier
Functional0.01-0.1%Up to 0.3%Used sparingly for depth

Classic Accords

Tip: Use in trace amounts to add mysterious depth without overwhelming compositions.

Alternatives & Comparisons

1
Ambroxan CAS 6790-58-5

More widely available amber alternative with similar longevity but less mineralic character.

2
Norlimbanol CAS 70788-30-6

Provides comparable woody-amber effects with better understood safety profile.

Layer 3

Safety, Regulatory & Sustainability

⚠ Regulatory Disclaimer

General reference only. Consult current IFRA Standards Library before formulating.

IFRA Status

Not currently restricted by IFRA standards.

RIFM Assessment

No RIFM assessment currently available for this material.

Sustainability

As a synthetic material, this compound avoids natural resource depletion but requires energy-intensive manufacturing. Its complex synthesis involves multiple steps with moderate atom economy. Future green chemistry approaches may improve its environmental footprint.

Explore (1a.alpha.,4.alpha.,7a.alpha.)-1a,3,3,4,6,6-Hexamethyl-1a,2,3,4,5,6,7,7a-octahydronapth[3,3-b]oxirene

Browse essential oils and aroma compounds.

Browse on iHerb →

Affiliate disclosure: we may earn a small commission at no extra cost to you.

References

    Data: PubChem (NIH), PubMed, RIFM, IFRA. Last reviewed: Apr 2026.

    Report a data error

    Ingredient Data Sheet

    CAS 94400-98-3

    Physical Properties

    Molecular Weight234.38 g/mol🔬 PubChem
    LogP (Octanol-Water)3.8🔬 PubChem
    Boiling Point287 °C🔬 EPA CompTox
    Vapor Pressure0.0001 mmHg @ 25°C📊 OPERA
    Flash Point124.5 °C🔬 EPA CompTox
    log Kp (skin permeability)-1.432💻 Calculated
    SMILESCC1CC(C2=C(C1(C)C)CC3(C(C2)O3)C)(C)C🔬 PubChem

    Volatility & Performance

    Fragrance NoteBase💻 Calculated
    Volatility ClassVery slow💻 Calculated
    Persistence Score8.9 / 5💻 Calculated

    Odor & Flavor

    Functional Groupsetheralkene💻 RDKit
    Data Sources & Attribution
    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: DTXSID50888739

    Physical Properties

    Molecular Weight 234.383 g/mol🔬 EPA CompTox
    Density 0.995 g/cm^3📊 OPERA
    Boiling Point 280.372 °C📊 OPERA
    Melting Point 72.655 °C📊 OPERA
    Flash Point 123.193 °C📊 OPERA
    Refractive Index 1.511 Dimensionless📊 OPERA
    Molar Volume 237.735 cm^3/mol📊 OPERA

    Partition & Solubility

    LogP (Octanol-Water) 4.489 Log10 unitless📊 OPERA
    LogD (pH 5.5) 4.489 Log10 unitless📊 OPERA
    LogD (pH 7.4) 4.489 Log10 unitless📊 OPERA
    LogKoa (Octanol-Air) 7.32 Log10 unitless📊 OPERA
    Water Solubility 0 mol/L📊 OPERA
    Henry's Law Constant 0 atm-m3/mole📊 OPERA

    Transport Properties

    Vapor Pressure 0.002 mmHg📊 OPERA
    Surface Tension 32.509 dyn/cm📊 OPERA

    Molecular Descriptors

    Topological Polar Surface Area 12.53 Ų💻 Computed
    H-Bond Donors 0 count💻 Computed
    H-Bond Acceptors 1 count💻 Computed
    Rotatable Bonds 0 count💻 Computed
    Aromatic Rings 0 count💻 Computed
    Molar Refractivity 71.172 cm^3/mol📊 OPERA
    Polarizability 28.215 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.

    Similar Posts